Em alta
Prévia do material em texto
SECTION X – SKIN INFECTIONS CHAPTER 64 – CUTANEOUS MANIFESTATIONS OF SYSTEMIC INFECTIONS James D. Cherry Many illnesses caused by infectious agents have associated cutaneous manifestations. In some cases, the exanthem may be the hallmark of the disease; in others, it may be only a vague indicator of a more significant underlying process. When an exanthem occurs, it often offers important clues to the etiology of a patient's illness. Although most exanthematous illnesses in children are benign, their differential diagnosis is critical because the early manifestations of potentially fatal bacterial and rickettsial diseases frequently have cutaneous findings. HISTORY Exanthematous manifestations of infectious illnesses have been important since medical antiquity. Major epidemics of both measles and smallpox occurred in the Roman Empire and in China at the beginning of the Christian era.[25,][130] Scarlet fever was recognized as a distinct entity in the 17th century, and chickenpox and rubella were identified in the 18th and 19th centuries, respectively.[49] In the writings of the early 20th century, maculopapular exanthematous illnesses of children frequently were referred to by number. Scarlet fever and measles historically were the first two classic maculopapular exanthems of childhood. Which one had the honor of being the “first disease” is unknown today. The “third disease” was rubella, which was recognized by the beginning of the 20th century as a distinct entity.[68,][70,][87,][157,]178-180 In 1900, Dukes[68] described an exanthematous illness with the characteristics of both rubella and scarlet fever, which he suggested was a “fourth disease.” The general opinion today is that his disease was not a distinct entity. Shaw[180] suggested that Dukes' cases had mild atypical scarlet fever, and Powell[157] raised the possibility that the illness resulted from epidermolytic toxin–producing staphylococci. Most probably, rubella and scarlet fever both were epidemic in the student population under Dr. Dukes' care; combined infections led to the confusion. Erythema infectiosum (see Chapter 164) commonly is referred to as the fifth disease, and roseola infantum (see Chapter 65) qualifies as the sixth disease.[179] During the last 55 years, interest in exanthematous diseases has been renewed because a large number of previously unknown viruses and other infectious agents that cause cutaneous manifestations have been discovered. In addition, the pattern of disease caused by classic exanthem-producing agents has changed; smallpox has been eradicated, the epidemiology of measles and rubella has been altered by immunization, and ecologic changes have resulted in differences in viral and bacterially induced rashes. ETIOLOGIC AGENTS Many different types of viruses, chlamydiae, rickettsiae, mycoplasmas, bacteria, fungi, and protozoan and metazoan agents cause illnesses with associated cutaneous manifestations. Although this chapter is devoted to systemic infectious diseases with cutaneous manifestations, the demarcation between exanthematous disease of systemic and local origin is not always readily apparent. For example, the recurrent cold sore caused by herpes simplex virus (HSV) infection frequently is considered a local problem, although its nature and pathogenesis involve central virus latency and host systemic immune functions. Similarly, superficial fungal diseases and other local infections, such as warts, may be quite dependent on more general immunologic functions of the host. The exanthems of enteroviral infections frequently are confused with those caused by insect bites and allergic problems. Table 64-1 presents viruses that have cutaneous manifestations in humans. Erythema infectiosum is caused by human parvovirus B19.[7,][205] This virus also is an important cause of the papular-purpuric gloves and socks syndrome that is an uncommon occurrence and mainly affects young adults.[3,][6,][50,][85,][91,][184,][185] Human parvovirus B19 also has been associated with a vesiculopustular exanthem, erythema multiforme, and other petechial and purpuric rashes. In one study, an erythematous maculopapular rash was noted in 9 percent of children with human bocavirus infections.[8] Adenovirus types 1, 2, 3, 4, 7, and 7a have been isolated from children and young adults with exanthem.[49,][110,][208,][209] The overall clinical expression rate of exanthem in adenovirus infection rarely has been studied. Fukumi and associates[79] noted that rash occurred in 2 percent of adenoviral infections; Hope-Simpson and Higgins[98] indicated a rate of approximately 8 percent. TABLE 64-1 -- Clinical Characteristics of Viral Infections with Cutaneous Manifestations Virus Disease or Syndrome Incubation Period (days) Main Season Clinical Characteristics Exanthem Usual Duration (days) Lesions Distribution Human parvovirus B19 (see Figs. 64-6 to 64-8) Erythema infectiosum; gloves and socks syndrome 7-17 Winter and spring Biphasic illness with mild prodromal period with headache and malaise for 2-3 days, then 7-day symptom-free period, followed by typical exanthema Three-stage exanthema: initially, rash on cheeks (slapped-cheek appearance) and then erythematous maculopapular rash on trunk and limbs; finally, rash develops a reticular pattern Starts on face More prominent on extensor surfaces of extremities 7-21 Human bocavirus Fall, winter, and spring Fever, cough, coryza, respiratory distress (bronchitis, bronchiolitis, pneumonia) Erythematous maculopapular Mainly face, chest, and trunk Human papillomaviruses Warts Nonseasonal Local cutaneous disease Papular or nodular isolated lesions Most common on extremities 100+ Adenovirus types 1, 2, 3, 4, 7, and 7a 6-9 Winter and spring Fever and signs and symptoms of respiratory illness Occasionally, rash occurs after defervescence (roseola-like) Most commonly erythematous, maculopapular, and discrete (rubelliform), but occasionally confluent (morbilliform) Rarely, erythema multiforme and Stevens-Johnson syndrome Usually starts on face and spreads downward to trunk and extremities 3-5 Herpes simplex types 1 and 2 (see Fig. 64-5) Cold sores, genital herpes, neonatal herpes, or other 2-12 Nonseasonal Primary disease associated with fever and systemic symptoms Recurrent disease caused by exogenous and endogenous infections Singular or grouped vesicular lesions varying in size from 2 to 10 mm, frequently on a mildly erythematous base Occasionally, erythema multiforme, Stevens-Johnson syndrome, and erythema nodosum Lesions in primary infection with type 1 virus are mainly in and around the mouth Recurrent type 1 lesions usually perioral Primary and recurrent type 2 lesions usually on genitals 7-14 Human herpesvirus–6 (HHV-6) Roseola infantum Nonseasonal Fever 3-5 days in duration, rapid defervescence, and then the appearance of rash Erythematous macular or maculopapular Most prominent on neck and trunk Face and extremities may be affected 1-2 Human herpesvirus–7 (HHV-7) Roseola infantum Nonseasonal Fever 3-5 days in duration, rapid defervescence, and then the appearance of rash Erythematous macular or maculopapular Most prominent on neck and trunk Face and extremities may be affected 1-2 Human herpesvirus–8 (HHV-8) Kaposi sarcoma Months to years Nonseasonal Asymptomatic infection Most commonly noted in AIDS patients but occurs in other immunodeficiency states Purple to blue nodular, raised lesions Any epidermal or mucosal surface Months to years Varicella-zoster (see Fig. 64-4) Chickenpox (varicella) 12-20 Late fall, winter, and spring Malaise and fever of 5-6 days duration Basiclesion is vesicular, but lesions go through stages: macules, papules, vesicles, and crusts Lesions occur in crops Lesions more profuse on trunk than on extremities Proximal end of extremities more involved than distal end 8-10 Herpes zoster Nonseasonal Endogenous infection Pain and paresthesia with dermatome distribution Basic lesion is vesicular, but lesions go through stages: macules, papules, vesicles, and crusts Lesions localized to area of skin innervated by a single sensory ganglion 10-28 Epstein-Barr Infectious mononucleosis 28-49 Nonseasonal Fever, pharyngitis, and lymphadenopathy Exanthem occurs in 3-13% of cases If ampicillin is administered, then exanthema in 50% of cases Most commonly erythematous, macular, maculopapular, and discrete (rubelliform) In association with ampicillin administration, the rash may be more vivid Erythema multiforme and urticaria may occur Mainly on trunk and proximal end of extremities 2-7 Cytomegalovirus Cytomegalovirus mononucleosis Nonseasonal Acquired: mild febrile illness with lymphadenopathy Congenital: disseminated disease Erythematous, maculopapular, and discrete Vesicular or petechial in congenital infection Located mainly on trunk and proximal end of extremities 2-7 Vaccinia Roseola vaccinatum, eczema vaccinatum, vaccination “take,” or disseminated vaccinia Nonseasonal Illness caused by direct exposure via vaccination or exposure to a vaccinee Vaccination and eczema vaccinatum lesions go through stages: papule, vesicle, pustule, and scab Roseola vaccinatum: erythematous maculopapular lesions Occasionally erythema multiforme Disseminated vaccinia: papular or vesicular lesions Lesions in roseola vaccinatum, eczema vaccinatum, and disseminated vaccinia are generalized 7-14 Variola Smallpox 8-17 Seasonal by geographic area Abrupt onset of high fever, headache, and muscle and joint pain Rash appears 2-4 days after onset Basic lesion is vesicular, but lesions go through stages: macules, papules, vesicles, pustules, and crusts Most prominent on exposed body surfaces Starts on extremities and face Spreads centripetally 12-20 Monkeypox Similar to mild smallpox Exposure to monkeys No human-to-human spread Similar to mild smallpox Similar to mild smallpox Orf Ecthyma contagiosum 4-7 Spring Disease of sheep acquired by humans Initially erythematous papule Becomes umbilicated, nodular, and then vesicular Occasionally erythema multiforme Solitary lesion, usually on hands 30-40 Molluscum contagiosum Molluscum contagiosum Local cutaneous disease Umbilicated nodular lesions: singular or clusters Most common on face, inner aspect of thigh, breasts, and genitalia 100+ Paravaccinia Milker's nodules 4-7 Human infection acquired from infected calves Nodular lesion Occasionally erythema multiforme Solitary lesion, usually on hands 30-40 Tanapox A virus of monkeys Human infection associated with fever and regional lymphadenopathy Umbilicated vesicular lesion Upper part of body Solitary lesion 35-56 Coxsackieviruses A2, A4, A5, A7, A9, A10, and A16; coxsackieviruses B1-B5; echoviruses 1-7, 9, 11-14, 16-19, 22, 24, 25, 30, and 33; enterovirus 71 (see Figs. 64-9 to 64-16) 4-7 Summer and fall Fever and mild to moderate pharyngitis Occasionally, herpangina, meningitis, and other manifestations of systemic viral infection Exanthem occurs in 5-50% of infections, depending on virus type Rash may occur during fever or after defervescence; hand, foot, and mouth syndrome Most commonly erythematous, maculopapular, and discrete May have macular, petechial, vesicular, and urticarial components Rarely erythema multiforme Usually starts on face and spreads downward to trunk and extremities May have peripheral distribution (hand, foot, and mouth syndrome) 3-7 Rhinoviruses (many types) 2-4 Fall, winter, and spring Mild fever and signs and symptoms of respiratory illness Exanthem occurs in about 5% of cases Erythematous or maculopapular and discrete Starts on face and spreads downward to trunk and extremities 1-4 Foot and mouth 3-4 Direct animal contact Fever, sore mouth, and lymphadenopathy Vesicles and ulcers within the mouth Vesicular lesions Hands and feet 3-6 Colorado tick fever 3-5 Summer Fever, chills, eye pain, myalgia, and headache Diphasic course Rash in only about 10% of cases Occasionally maculopapular but usually petechial Maculopapular rash is generalized Petechial rash most prominent on arms, legs, and trunk 2-7 Reovirus 2 and 3 4-7 Summer Fever, mild pharyngitis, and cervical adenopathy Erythematous or maculopapular Discrete or confluent Occasionally vesicular Starts on face and spreads downward to trunk and extremities 3-9 Rotavirus Gianotti-Crosti syndrome; infantile acute hemorrhagic edema 2-4 Fall, winter, and spring Gastroenteritis Petechial and morbilliform Generalized 7-14 Chikungunya, o'nyong-nyong, Ross River, Sindbis During periods of arthropod prevalence Fever, headache, eye pain, and marked myalgia, arthralgia, and arthritis Geographically localized diseases Rubelliform and morbilliform Frequently vesicular and petechial Starts on face and spreads downward to trunk and extremities Rubella (see Fig. 64-3) Rubella (German measles) 15-21 Winter and spring Mild symptoms with onset 1-5 days before rash Fever usually <38.5° C (101.5° F) Headache, malaise, and suboccipital and postauricular lymphadenopathy Erythematous, maculopapular, and discrete Starts on face and spreads downward to trunk and extremities 4-7 West Nile Sudden onset of fever, chills, and drowsiness Rash may appear during or after fever Geographically localized disease Erythematous, macular, and maculopapular Starts on trunk and spreads to extremities 3-6 Dengue and Kunjin 7 During periods of specific arthropod prevalence Sudden onset of high fever, then severe headache, myalgia, arthralgia, abdominal pain, and marked diaphoresis Fever lasts 5-6 days and ends by crisis Rash appears within 48 hours of onset of fever Geographically localized diseases Initially, macular, flushed appearance, then erythematous, maculopapular rash May be scarlatiniform Frequently becomes petechial and purpuric Small vesicles occur in Kunjin virus infection Initial macular rash is more prominent centrally Maculopapular rash may start on hands and feel and spread to trunk 3-10 Influenza A and B 2-5 Fall, winter, and spring Fever, cough, headache, and muscle aches and pains Usually in young children Rash an occasional occurrence Erythematous, maculopapular, and discrete (rubelliform) Rarely erythema multiforme Starts on face and trunk and spreads to extremities 1-3 Respiratory syncytial 2-5 Fall, winter, and spring Fever, coryza, and respiratory distress (bronchitis, bronchiolitis, or pneumonia)Usually in children <2 years Erythematous, maculopapular, and discrete (rubelliform) Starts on face and trunk and spreads to extremities 1-3 Human metapneumovirus Fall, winter, and spring Fever, coryza, and respiratory distress (bronchitis, bronchiolitis, or pneumonia) Erythematous, maculopapular Parainfluenza 1-3 2-5 Fall, winter, and spring Fever, coryza, nasopharyngitis, croup, and bronchitis Usually in young children Erythematous, maculopapular, and discrete (rubelliform) Starts on face and trunk and spreads to extremities 1-3 Mumps Mumps 14-21 Fall, winter, and spring Fever, headache, and salivary gland swelling Erythematous, maculopapular, and discrete; also, urticaria and vesicles; rarely, erythema multiforme Most prominent on trunk 2-5 Measles (see Figs. 64-1 and 64-2) Measles 8-12 Winter and spring Onset with fever, cough, coryza, and conjunctivitis About 2 days after onset, appearance of enanthem (Koplik spots); and 2 days later, onset of exanthem Erythematous, maculopapular, and confluent Develops a brownish appearance, and fine desquamation occurs Starts behind ears and on forehead Spreads downward over body Confluence most prominent on face, trunk, and proximal end of extremities 5-7 Lassa Lassa fever Sudden onset of fever, chills, headache, and sore throat Progresses to pneumonia and renal failure Geographically localized outbreaks Macular and sometimes petechial Localized or general Hepatitis B Papular acrodermatitis of childhood 50-180 Insidious onset with arthralgia, arthritis, and rash occurring before jaundice Maculopapular, macular, or urticarial In young children, papular (Gianotti-Crosti syndrome or papular acrodermatitis of childhood) Rarely, erythema multiforme Generalized 4-10 Hepatitis C Mixed cryoglobulinemia (not reported in children) 7-14 Nonseasonal Acute hepatitis followed by chronic infection Skin findings occur late in disease Palpable purpura Mostly buttocks, lower extremities Variable Marburg 5-7 Headache, conjunctivitis, photophobia, myalgia, vomiting, diarrhea, and fever (biphasic) Exposure to vervet monkeys Initially erythematous macular, then discrete maculopapular, and finally confluent maculopapular Exfoliation occurs Occasionally purpura Generalized 2-14 Ebola Hemorrhagic fever 5-10 Occurs in outbreaks Febrile illness that progresses to hemorrhage, shock, and coma Maculopapular rash that appears toward end of first week of illness Lateral sides of trunk, groin, and axillae Can become generalized but spares the face 14-60 Hantavirus Hemorrhagic fever with renal syndrome (nephropathia epidemica) Spring and summer outbreaks Febrile illness with hemorrhagic and renal manifestations Flushing and petechial rash Face (flushing), skin folds (petechiae) 14-28 HIV 14-60 Nonseasonal Fever, pharyngitis, myalgia, arthralgias, adenopathy, and rash Macular Mainly chest and abdomen 7 Human T-lymphotropic virus Infective dermatitis Nonseasonal Acute onset of eczema Severe exudative eczema with a crusting, generalized, fine papular rash Scalp, eyelid margins, perinasal skin, retroauricular areas, axillae, and groin Months to years Eight species in the Herpesvirus genus have cutaneous manifestations associated with infection, but clinical expression rates vary greatly. Nearly all primary varicella infections are associated with exanthem, whereas exanthem with acquired cytomegalovirus infection is a rare manifestation.[19,][22,][49,][166,][190,][208] The incidence of exanthem in Epstein-Barr virus infection varies from 3 percent to nearly 100 percent, depending on whether concomitant ampicillin is administered.[16,][28,][95,][104,][111,][146,][159,][197,][198] Although firm data are lacking, probably less than 10 percent of primary infections with HSV type 1 are associated with cutaneous manifestations. Erythema multiforme occasionally occurs with recurrent HSV infections.[36,][76,][107,][144] Human herpesvirus–6 (HHV-6) is a major cause of roseola infantum.[11,][205,][217] HHV-7 also is a cause of roseola infantum[10]; in addition, some evidence suggests that this virus may play a role in pityriasis rosea.[66] HHV-8 infection is necessary for the development of Kaposi sarcoma in patients with acquired immunodeficiency syndrome (AIDS) and other immunodeficiency states.[102,][114,][135] At present, human illnesses with cutaneous manifestations caused by poxviruses rarely occur. Because smallpox as a disease has ceased to exist, the use of vaccinia virus for immunization has decreased dramatically. However, the terrorist events of 2001 raised concern about the possible use of smallpox virus as a terrorist weapon. Because of this potential danger, smallpox vaccines are being produced and used again. With the increased use of these vaccines, cutaneous complications of vaccinia virus infection can be expected. Monkeypox, orf, and paravaccinia (milker's nodules) continue to occur as isolated events in exposed individuals.[170,][208,][209] Human infection with tanapox virus is a geographically related illness occurring in limited areas of Kenya. In the present era, enteroviruses are the leading cause of infection-related exanthematous diseases.[51,][55,][109,][208,][209] Thirty-seven types have been associated with rash illnesses. The clinical expression rate varies greatly among the different types; it is as high as 50 percent in children with coxsackievirus A16 and echovirus 9 infections. Only approximately 15 percent of individuals infected with echovirus 4 have exanthem, and rash is a rare occurrence in echovirus 6 infection. Hope-Simpson and Higgins[98] noted exanthem in approximately 5 percent of patients with rhinoviral respiratory illness. A young adult research worker had an influenza-like illness and a hand, foot, and mouth syndrome–like rash caused by infection with a calicivirus (San Miguel sea lion virus serotype 5) of oceanic origin.[183] Two percent of patients with Colorado tick fever encephalitis have exanthem.[51] Although infection with reoviruses occurs commonly, exanthem has been noted on only nine occasions.[51,][121] A morbilliform rash has been observed in one adult with a rotavirus infection, and a 4-year-old boy was noted to have a petechial rash in association with a rotaviral illness.[60,][167] Di Lernia and Ricci[63] described three cases of Gianotti-Crosti syndrome and one child with infantile acute hemorrhagic edema associated with rotavirus infections. Of the Togaviridae family of viruses, rubella virus is the most important as a worldwide cause of exanthematous disease. Several alphaviruses also frequently cause exanthems.[108,][141,][208,][209] Each of these viruses has a marked geographic distribution. Similarly, flaviviruses also have exanthem as part of their clinical expression, and they too have specific geographic boundaries.[208,][209] In the New York City area outbreak of West Nile virus infection in 1999, 19 percent of patients had exanthem.[138] The rash was erythematous macular, papular, or morbilliform. Exanthem generally is not considered to be a manifestation of influenza virus infection, but Hope-Simpson and Higgins[98] noted exanthem in approximately 8 percent of patients from whom influenza B virus was isolated and in 1 or 2 percent of those infected with influenza A virus. Measles virus is the most notable of the Paramyxoviridae family with an associated exanthem. However, exanthem occurs rather frequently in young children infected with parainfluenza virus types 1, 2, and 3 and also in those with respiratorysyncytial virus (RSV) illnesses.[81,][93,][94,][199,][202] Hope-Simpson and Higgins[98] noted a 15 percent incidence of rash in RSV infection and an approximately 15 percent incidence in parainfluenza virus infection. Rash, which was not described further, was observed in four children with respiratory illnesses caused by human metapneumovirus infections.[158] Exanthem also has been noted on rare occasion with mumps virus infection.[49] Lassa fever virus, Marburg virus, Ebola virus, and hepatitis B virus all have been associated with exanthem on occasion.[42,][46,][62,][75,][152,][208] Hepatitis B virus is the main cause of papular acrodermatitis (Gianotti-Crosti syndrome) in children.[46,][171,][175] Chronic hepatitis C virus infection occasionally causes systemic vasculitis and cryoglobulinemia in adults, with purpuric lesions concentrated on the lower extremities.[2,][97] Other cutaneous manifestations of chronic hepatitis C virus infection include urticaria, erythema nodosum, lichen planus, and nodular prurigo.[106,][216] Hantaviruses cause two major syndromes throughout the world: hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome.[4,][39,][150,][174] Exanthem (facial flushing and petechial lesions in skin folds) occurs in approximately 30 percent of patients with hemorrhagic fever with renal syndrome, but rash is not reported in the hantavirus pulmonary syndrome. A macular rash has been noted in association with acute infection with human immunodeficiency virus type 1 (HIV-1).[137,][139,][140,][189] Several reports have associated human T-lymphotropic virus type 1 (HTLV-1) with an atypical form of eczema called infective dermatitis. This exanthem has an acute onset and is somewhat recalcitrant to treatment.[116,][117,][126] Chlamydiae, rickettsiae, and mycoplasmas associated with cutaneous manifestations are listed in Table 64-2. Of the chlamydiae, only Chlamydia psittaci has been associated with exanthem. In contrast, all rickettsiae that infect humans, with the exception of Coxiella burnetii, usually display some cutaneous manifestations as part of their systemic disease.[31,][69,][84,][115,][122,][143,][147,][173] Approximately 4 to 7 percent of adults with Q fever have exanthem.[40,][187] Of the mycoplasmas that infect humans, only Mycoplasma pneumoniae is associated with exanthem.[13,][51,][53] In epidemics, exanthem occurs in approximately 15 percent of persons with respiratory illness. TABLE 64-2 -- Clinical Characteristics of Chlamydial, Rickettsial, and Mycoplasmal Infections with Cutaneous Manifestations Agent Disease or Syndrome Incubation Period (days) Main Season Clinical Characteristics Exanthem Usual Duration (days) Lesions Distribution Chlamydia psittaci Psittacosis 7-14 Nonseasonal Fever, chills, headache, and cough Respiratory distress Erythematous macules Occasionally erythema multiforme or erythema nodosum Mainly on trunk 2-7 Rickettsia akari Rickettsialpox 7-14 Nonseasonal Fever, chills, headache, backache, and malaise 4-7 days after onset of primary lesion at site of mite bite Geographically localized disease Initial lesion at site of mite bite is papular and then vesicular, and finally an eschar forms Two days after onset of fever, erythematous maculopapular discrete rash occurs Lesions progress to small vesicles and later to scabs Most prominent on trunk and proximal end of extremities 7-10 Rickettsia typhi Endemic, murine typhus 7-14 Nonseasonal Fever and headache Rash appears on 4th-7th day Geographically localized disease Initially discrete macules and then erythematous maculopapular May become purpuric Initially upper part of trunk and axilla Progresses to entire body except face, palms, and soles 7-21 Rickettsia prowazekii Epidemic typhus 10-14 Nonseasonal Sudden onset of fever, chills, headache, and myalgias Rash appears on 4th-7th day Geographically localized disease Initially discrete macules and then progresses to maculopapular and petechial lesions Sometimes purpuric Appears first on trunk and spreads to extremities Spares palms and soles 7-14 Rickettsia tsutsugamushi Scrub typhus 7-21 Nonseasonal Sudden onset of chills, fever, and headache Local lesion at site of chigger bite is present at onset of symptoms; characterized by vesicle, ulcer, and eschar Maculopapular rash occurs 5-8 days after onset of fever Maculopapular rash first occurs on trunk and then becomes generalized 7-14 Rickettsia rickettsii Rocky Mountain spotted fever 3-12 Summer Abrupt onset of fever, chills, and headache Rash appears 2-4 days after onset Early maculopapular, then petechial, and sometimes purpuric Rash starts on distal end of extremities Rarely involves the trunk 7-14 Other tick-borne rickettsiae Tick seasons Similar to mild Rocky Mountain spotted fever Similar to Rocky Mountain spotted fever; eschar at site of tick bite Similar to Rocky Mountain spotted fever 7-14 R. sibirica North Asian tick-borne rickettsiosis R. australis Queensland tick typhus R. conorii Boutonneuse fever R. africae African tick fever Coxiella burnetii Q fever 20-40 Nonseasonal Acute febrile illness with chills, headache, and myalgia Fine discrete macular rash occurring during febrile illness Transient urticarial rash also noted Mainly on trunk 2-7 Ehrlichia species Ehrlichiosis 14-28 Tick seasons Similar to Rocky Mountain spotted fever, but rash usually not on palms and soles Similar to endemic typhus Similar to endemic typhus 7-14 Mycoplasma pneumoniae 21 All seasons Gradual onset of fever, malaise, headache, and cough Maculopapular rash occurs in 5-15% of cases Vesicular and bullous lesions common (Stevens-Johnson syndrome); more common in males Papular, petechial, and urticarial lesions also noted Erythema multiforme common Rash most prominent on trunk and proximal end of extremities 7-14 In Table 64-3, bacterial agents for which cutaneous manifestations are part of the clinical illness are presented (see Chapter 66). The clinical expression of exanthem varies tremendously among the different etiologic agents, as do the conditions associated with a specific infection. For example, infection with phage group 2 staphylococci usually results in cutaneous disease in young infants, whereas the same organisms rarely cause illness in adults. Symptomatic infection with Streptococcus pneumoniae is associated with cutaneous manifestations only occasionally; on the other hand, similar systemic disease with Neisseria meningitidis virtually always is associated with the characteristic petechial exanthem. Of the other bacterial agents listed in Table 64-3, exanthem is most important in the following: Neisseria gonorrhoeae, Salmonella typhi, Streptobacillus moniliformis, Spirillum minus, Pseudomonas aeruginosa, and Treponema pallidum. TABLE 64-3 -- Bacteria Associated with Cutaneous Manifestations Exanthem Agent Disease or Syndrome Clinical Characteristics Lesions Distribution Gram-positive cocci Staphylococcus aureus, exfoliative toxin-producing, mainly phage group 2 (see Figs. 64-17 and 64-18) Bullous impetigo Usually occurs in neonates May be epidemic Rapid progression from vesicles to bullous lesions Most common in diaper area Scalded skin syndrome Toxic epidermal necrolysis (Ritter diseasein infants <4 months; Lyell syndrome in older children) Usually occurs in infants and children 1 month–5 years of age Mucopurulent nasal and eye discharge Fever Scarlatiniform eruption with exfoliation Nikolsky sign present Crusty appearance around eyes and under nose Generalized Most marked on trunk Staphylococcal scarlet fever or staphylococcal scarlatiniform eruption Fever and staphylococcal infection in throat, but no evidence of pharyngitis Scarlet fever–like rash with desquamation Pastia lines present Generalized Staphylococcus aureus, non–exfoliative toxin-producing Septicemic disease Severe septicemia with osteomyelitis, arthritis, endocarditis, or pneumonia Diffuse, erythematous, confluent, and macular rash (flush) With endocarditis, may have petechiae and splinter hemorrhages, Osler nodes, Janeway spots Trunk and proximal end of extremities Staphylococcus aureus, toxin-l (TSST-1)– producing Toxic shock syndrome Fever, intense myalgias, vomiting, and diarrhea Mental confusion and hypotension Erythematous, deep red (sunburn-like) rash Desquamation occurs Generalized Staphylococcus aureus, non–exfoliative toxin-producing Folliculitis, furuncles, or carbuncles See primary skin infections, Chapter 66 Streptococcus pyogenes Scarlet fever Fever, pharyngitis, and cervical lymphadenitis Rash onset within 2 days of first symptoms Incubation period 3-4 days Diffuse erythematous and fine maculopapular (looks and feels like red sandpaper) Rash darker in skin folds (Pastia lines) Desquamation occurs Circumoral pallor Generalized rash, with trunk and proximal end of extremities being most involved Erysipelas Fever, headache, and vomiting Localized infection Circumscribed area that is raised and erythematous Advancing edge is irregular Anywhere Impetigo Localized superficial pyoderma See primary skin infections, Chapter 66 Discrete and coalescent lesions of a vesicular nature Quickly becomes more pustular and then crusts over with a yellowish brown appearance Forearms, legs, and face Septicemia Fever and systemic foci of infection Petechiae Diffuse Miscellaneous skin manifestations of S. pyogenes infections Erythema multiforme, erythema nodosum, and erythema marginatum Streptococcus pneumoniae Septicemia Fever Petechiae Diffuse Enterococcal and viridans group streptococci Endocarditis Endocarditis Petechiae, splinter hemorrhages, Osier nodes, and Janeway spots Gram-negative cocci Neisseria gonorrhoeae Gonococcemia Fever and polyarthralgias Papular, petechial purpuric, pustular, or necrotic lesions Most common on extremities Extensor surfaces over joints Neisseria meningitidis Meningococcemia Fever and pharyngitis Sudden onset of rash Characteristic rash is petechial or purpuric Early lesions may be erythematous maculopapular, or urticarial Generalized Moraxella catarrhalis Bacteremia Fever and pharyngitis Maculopapular and petechial Generalized Gram-positive bacilli Bacillus anthracis Anthrax Fever, headache, malaise, and joint pain Initially, macular, pruritic lesion Later, a papule forms and then vesiculation Vesicles last 2-6 days, and then eschar forms Usually, single lesion initially at point of exposure, secondary lesions in area develop later Listeria monocytogenes Listeriosis Neonatal meningitis with hepatosplenomegaly Maculopapular, discrete lesions Pustules Trunk and legs Erysipelothrix rhusiopathiae Crab or fishnet dermatitis Fever and local pain Erysipeloid lesion (violet or red) Hands Corynebacterium diphtheriae Cutaneous diphtheria Secondary infection in cutaneous wounds Impetigo or ecthyma-like Rarely, erythema multiforme Exposed surfaces Arcanobacterium hemolyticum Scarlet fever–like illness Fever and pharyngitis Scarlet fever–like rash Occasionally, rubelliform Generalized rash with peripheral predominance Enteric gram-negative bacilli Salmonella typhi Typhoid fever Malaise, headache, and marked fever Rash onset 10 days after onset of fever Rose spots, 2- to 4-mm macular lesions Discrete lesions on abdomen Other Salmonella species Septicemic salmonellosis Similar to mild typhoid fever Similar to typhoid fever Similar to typhoid fever Shigella sonnei Shigellosis Diarrhea Urticaria Diffuse Campylobacter species Gastroenteritis Skin pustules and erythema nodosum Lower part of legs Other gram-negative bacilli Francisella tularensis Tularemia Chills, fever, headache, and localized lymphadenopathy Initial papule that later ulcerates Site of inoculation Haemophilus ducreyi Chancroid Local pain and tenderness Pustular lesions that ulcerate External genitalia Haemophilus influenzae Septicemia Fever Petechiae Reddish purple cellulitis Diffuse Cellulitis mainly on cheeks and extremities Streptobacillus moniliformis Rat-bite fever Fever, chills, malaise, headache, and polyarthritis Erythematous, maculopapular rash that may become petechial Most prominent on extremities, including palms and soles Yersinia pestis Septicemic plague Sudden onset of fever Initial generalized erythema followed by petechiae and purpura Generalized Yersinia pseudotuberculosis Mesenteric lymphadenitis Erythema nodosum and scarlatiniform eruption Lower part of legs and generalized Yersinia enterocolitica Yersiniosis Enterocolitis Erythema nodosum and urticaria Lower part of legs and generalized Bartonella bacilliformis Bartonellosis, Carrión disease, or Oroya fever Initially intermittent fever, malaise, and myalgias 30-60 days after initial fever, exanthem appears Erythematous maculopapular Later recurrent nodules Face and extensor surface of extremities Bartonella quintana Trench fever Usually mild fever, headache, chills, and tibial bone pain Macular rash Mainly on trunk Calymmatobacterium granulomatis Granuloma inguinale See Calymmatobacterium granulomatis, Chapter 141 Nodular, ulcerovegetative, hypertrophic, or cicatricial lesions Genitals Pseudomonas aeruginosa Ecthyma gangrenosa Septicemia (usually in immunocompromised patients) Initially vesicular and then hemorrhagic Become ulcerated with central black necrotic eschar Anywhere Pseudomonas folliculitis (health spa dermatitis) Headache, malaise, and fatigue Papular and pustular Generalized Burkholderia mallei Glanders, melioidosis Fever, malaise, chills, arthralgia, and muscle pains Nodule or ulcer at site of inoculation and then widespread papules, bullae, and pustules Generalized Brucella species Brucellosis Acute or subacute febrile illness Exanthem in 8% of cases Erythematous and maculopapular Occasionally vesicles Generalized Legionella pneumophila Legionnaires' disease Severe pneumonia Maculopapular Anterior of trunk Bartonella henselae Cat-scratch fever Subacute regional lymphadenitis Erythematous maculopapular, morbilliform, petechial, erythema nodosum, erythema multiforme, and erythema marginatum May be pruritic Generalized Acid-fastbacilli Mycobacterium tuberculosis Lupus vulgaris Usually associated with other manifestations of tuberculosis Reddish brown nodular or scaling lesions Mainly on face and neck Papulonecrotic tuberculids Associated with disseminated tuberculosis Initially vesicular Become pustules, umbilical, and ulcerated and then form scabs and leave scars Single or multiple lesions anywhere Atypical mycobacteria Granulomatous and ulcerative lesions at site of superficial injury Usually on hands Mycobacterium leprae Erythema nodosum leprosum General findings of lepromatous leprosy Erythematous nodular lesions Disseminated Most prominent on face and extremities Spirochetes Treponema pallidum Primary syphilis Secondary syphilis Chancre Large ulcers with indurated edges Erythematous maculopapules that frequently are scaly (psoriasiform) Genitals Generalized, including palms and soles Treponema pertenue Yaws Papular lesions at sites of inoculations Lesions ulcerate, leaving a wart-like appearance Anywhere Borrelia burgdorferi Lyme disease (erythema chronicum migrans) Skin, cardiac, neurologic, and joint abnormalities Expanding erythematous, annular lesions Thighs, buttocks, or axillae Treponema carateum Pinta Initially, erythematous, papular lesions; increase in size during 1-month period and become scaly Exposed surfaces of body Spirillum minus Rat-bite fever Fever and chills Discrete, macular rash Trunk and extremities, including palms and soles Leptospira species Leptospirosis Fever, conjunctivitis, and anorexia Rash rarely noted Erythematous maculopapular rash Mainly on trunk Borrelia species Relapsing fever Relapsing fever, headache, myalgia, and photophobia Morbilliform and petechial Erythema multiforme Generalized Fungal, protozoan, and metazoan agents associated with cutaneous manifestations in humans are listed in Tables 64-4, 64-5, and 64-6, respectively. These agents and their diseases, discussed more completely in other chapters, are included here for completeness of the differential diagnosis. TABLE 64-4 -- Fungi Associated with Cutaneous Manifestations Exanthem Agent Disease or Syndrome Clinical Characteristics Lesions Distribution Dermatophytic fungi Tinea capitis, tinea cruris, tinea pedis, or tinea circinata Localized, brownish, maculopapular lesions that are scaly Erythema nodosum Candida albicans Congenital cutaneous candidiasis Congenital infection Discrete vesicular lesions Generalized Chronic mucocutaneous candidiasis Immunodeficiency disease Confluent, erythematous, and exudative lesions Generalized, including scalp Acquired candidiasis Confluent, fiery red lesions Most common in diaper area Candida spp. Systemic candidiasis Severe opportunistic infection Erythematous nodular lesions Generalized Histoplasma capsulatum Histoplasmosis Primary respiratory infection Erythema nodosum, erythema multiforme, and erythematous maculopapular Cryptococcus neoformans Cryptococcosis Primary respiratory infection Erythema nodosum and acneiform eruptions Coccidioides immitis Coccidioidomycosis Primary respiratory infection Initially, erythematous, maculopapular rash Later, erythema multiforme and erythema nodosum Generalized maculopapular rash Sporotrichum schenckii Sporotrichosis Cutaneous inoculation Nodular lesions that ulcerate Usually, hands, arms, and legs Blastomyces dermatitidis Blastomycosis Primary respiratory infection Nodular lesions that ulcerate Erythema nodosum Scedosporium spp. No specific syndrome Severe opportunistic infection Nodular or necrotic skin lesions Generalized Fusarium spp. No specific syndrome Severe opportunistic infection Nodular skin lesions, abscesses Generalized Aspergillus spp. No specific syndrome Severe opportunistic infection Nodular and purpuric lesions Generalized TABLE 64-5 -- Cutaneous Manifestations of Protozoan and Helminthic Infections Agent Disease or Syndrome Cutaneous Manifestations Plasmodium spp. Malaria Occasionally generalized urticaria in chronic infection Toxoplasma gondii Acquired toxoplasmosis Occasionally generalized erythematous, maculopapular rash Congenital toxoplasmosis Generalized petechial rash Giardia lamblia Giardiasis Rarely urticaria Entamoeba histolytica Amebiasis Rarely urticaria Leishmania tropica Oriental sore Red nodular lesion that ulcerates; lasts 2-3 months Leishmania braziliensis and mexicana American cutaneous leishmaniasis Erythematous papular lesion that vesiculates and ulcerates Trypanosoma gambiense African trypanosomiasis Red nodular lesion at site of bite, followed by generalized, pruritic, erythema multiforme–like rash Trypanosoma cruzi American trypanosomiasis or Chagas disease Nodular lesion at site of bite; generalized recurrent erythematous, maculopapular rash Trichomonas vaginalis Vulvovaginalis Rarely urticaria and erythema multiforme Ascaris lumbricoides Roundworm infestation Erythema nodosum Enterobius vermicularis Pinworm infestation Rarely urticaria Necator americanus Hookworm disease Papules and papulovesicles on exposed surfaces (feet); generalized urticaria Trichinella spiralis Trichinosis Urticaria common; also, generalized maculopapular rash may occur; petechiae frequently develop Strongyloides stercoralis Strongyloidiasis; also, creeping eruption (cutaneous larva migrans) Erythematous, maculopapular lesions on feet; creeping eruption Ancylostoma braziliense Creeping eruption (cutaneous larva migrans) Creeping eruption Dermatobia hominis Cutaneous myiasis Creeping eruption, subacute draining lesions Schistosoma haematobium, mansoni, and japonicum Schistosomiasis Pruritic papular eruption where exposed; generalized urticaria and granulomatous lesions Trichobilharzia ocellata, physellae, and stagnicolae Swimmer's itch or collector's itch Initial erythema and urticaria followed by papules and vesiculation; pruritic Wuchereria bancrofti Filariasis Localized erythema urticaria and erythema nodosum Onchocerca volvulus Onchocerciasis Chronic, papular, scaly rash Echinococcus granulosus and multilocularis Echinococcosis Frequent urticaria TABLE 64-6 -- Cutaneous Manifestations of Arthropod Bites and Stings Agent Disease or Syndrome Cutaneous Manifestations Spiders Loxosceles rectus Recluse spider bite or brown spider bite Erythema followed by blister and necrosis Ticks Tick bite Initial pruritus at site; becomes ulcerated and granulomatous Mites Sarcoptes scabiei Scabies Pruritic burrows in body creases and generalized; become erythematous and then papular urticaria Trombicula irritans Chigger bite Marked pruritus and then papular urticaria Other mites: food, grain, murine, and fowl Marked pruritus and then papular urticaria Lice Pediculus humanus Body lice or pediculosis Erythematous, maculopapular, pruritic lesions; sometimes urticaria Phthirus pubis Crabs Pruritus and erythema under pubic hair Bedbugs and kissing bugs Cimex lectularius Bedbug bite Pruritic papular urticaria Triatoma sanguisuga Kissing bug bite Papular urticaria; occasionally hemorrhagic nodular lesions Gypsy moth caterpillar Lymantria dispar Gypsy moth rash Pruritic blotchy erythema and maculopapular Moths Hylesia alinda Moth-associated dermatitis Erythemaand pruritus; feeling of warmth in area of rash; may have vesicular lesions Ants Solenopsis saevissima Fire ant bite Painful papular urticarial lesions that become pustular and then nodular Fleas Pulex irritans (human flea) and fleas of many animals Flea bite Papular urticaria Flies and mosquitoes Fly and mosquito bite Papular, nodular, and urticarial lesions in sensitive persons EPIDEMIOLOGY Tables 64-1 through 64-6 clearly show that exanthematous disease has many possible etiologic agents; hence, no unified epidemiology exists. Epidemiologic events related to specific agents are considered in the appropriate sections throughout this text. Each agent with exanthem as a clinical manifestation has a unique epidemiologic pattern that, if understood, distinguishes it from many of the other agents that cause otherwise identical clinical illnesses. In the evaluation of all patients with rash, exposure, season, and incubation period are important aspects of the diagnostic process. PATHOPHYSIOLOGY AND PATHOLOGY OF EXANTHEMS Even though the skin can respond in only a limited number of ways, what is obvious from the extensive number of etiologic agents is that multiple pathogenic mechanisms must occur. In many sections of this book, the pathology and pathophysiology of specific agents are presented in detail. An overview is presented here. Small vessel vasculitis (leukocytoclastic vasculitis) is a leading event in most exanthematous illnesses caused by infectious agents.[186] The cutaneous manifestations of systemic diseases can be separated into three broad categories. The first category involves dissemination of infectious agents by blood (viremia, bacteremia, and so on), which results in secondary infection at the cutaneous site. The clinical cutaneous findings in this type of infection can be the direct result of infectious agents in the epidermis, dermis, or dermal capillary endothelium or can be the result of an immune response between the organism and antibody or cellular factors in the cutaneous location. The possible events in the skin with this type of infection are presented in Table 64-7. Chickenpox, many enteroviral infections, and meningococcemia are examples of diseases in which infectious agents have reached the skin through the blood and are causing the cutaneous findings without the additional contribution of host immune factors. In illnesses such as measles, rubella, and gonococcemia, the timing, histologic picture, and difficulty of direct recovery of the agent by culture suggest both a direct effect and an immune-mediated response. TABLE 64-7 -- Aspects of Pathogenesis in Exanthems Associated with Blood-borne Dissemination of the Infectious Agent Modified from Cherry, J. D.: Newer viral exanthems. Adv. Pediatr. 16:233-286, 1969. The second category of pathogenesis relates to the dissemination of known specific toxins of infectious agents. The infection is in a localized area of the body, but the toxin liberated by the infectious agents reaches the skin by blood-borne dissemination. Three examples of toxin-mediated exanthematous disease are streptococcal scarlet fever, staphylococcal scalded skin syndrome, and toxic shock syndrome. The third category of pathogenesis in systemic disease with exanthem is poorly understood but appears to have an immunologic basis. Most important in this category are the clinical pictures of erythema multiforme, erythema multiforme exudativum (Stevens-Johnson syndrome), and erythema nodosum. In erythema multiforme associated with M. pneumoniae and HSV infection, the respective organisms have been isolated or identified at the skin site. In most instances, however, neither antigen localization nor disseminated toxin has been identified. Important clinical aspects of exanthematous diseases are the distribution and progression of the lesions, yet little is known of the cause of these aspects. Differences in skin thickness, vascularity, proliferation rate, temperature, and metabolic activity are important in animal diseases with cutaneous manifestations.[51,][75,][124,][134,][154] In humans, similar factors must be important but obviously affect the various etiologic agents differently (e.g., the more central exanthem of chickenpox versus that of the hand, foot, and mouth syndrome of coxsackievirus A16 infection). CLINICAL MANIFESTATIONS The clinical findings in exanthematous diseases resulting from systemic infections are varied and depend on the inciting pathogens. By examination of skin alone, differentiating an exanthematous disease resulting from systemic infection (e.g., coxsackievirus A9, rubella virus infection) from primary cutaneous diseases of infectious and noninfectious origin (insect bites, acne, and contact with poison ivy) frequently is difficult. In Tables 64-1 through 64-6, the clinical characteristics of viral, chlamydial, rickettsial, bacterial, fungal, parasitic, and arthropod-induced illnesses with primary or secondary cutaneous manifestations are presented. In Tables 64-8 through 64-17, etiologic agents and clinical manifestations are presented on the basis of the more pronounced cutaneous manifestations or syndrome associations. The clinician must keep in mind that other aspects of an illness (e.g., exposure, season, incubation period, geographic location, patient age, associated signs and symptoms) may be more important in determining the underlying etiologic agent. Clinical manifestations of specific exanthematous diseases are presented in greater detail in other chapters of this book. TABLE 64-8 -- Infectious Agents Associated with Illness in Which a Macular Exanthem Has Been Observed Infectious Agent Illness Human herpesvirus-6, −7 Roseola infantum Epstein-Barr virus Infectious mononucleosis Coxsackieviruses Bl, B2, B5 — Echoviruses 2, 4, 5, 14, 17-19, 30 — Enterovirus 71 — Dengue virus Dengue fever Lassa virus Lassa fever Marburg virus Marburg fever Parvovirus Erythema infectiosum HIV-1 Manifestation of acute infection Hantavirus Hemorrhagic fever with renal syndrome Chlamydia psittaci Psittacosis Rickettsia typhi Murine typhus Rickettsia prowazekii Epidemic typhus Rickettsia quintana Trench fever Coxiella burnetii Q fever Mycoplasma pneumoniae — Staphylococcus aureus Septicemia and toxic shock syndrome Streptococcus pyogenes Scarlatina and septicemia Bacillus anthracis Anthrax Salmonella typhi Typhoid fever Salmonella species Septicemic salmonellosis Spirillum minus Rat-bite fever Leptospira species Leptospirosis Yersinia pestis Plague TABLE 64-9 -- Infectious Agents Associated with Illnesses in Which Maculopapular Exanthems Occur Character of Rash Infectious Agent Illness Discrete Confluent Parvovirus Erythema infectiosum +++ + Human bocavirus ++++ Adenoviruses 1, 2, 3, 4, 7, 7a +++ + Human herpesvirus–6 Roseola infantum +++ + Epstein-Barr virus Infectious mononucleosis +++ + Cytomegalovirus ++++ Vaccinia virus Roseola vaccinatum +++ + Coxsackieviruses A2, A4, A5, A7, A9, A10, A16 +++ + Coxsackieviruses B1-B5 +++ + Echoviruses 1-7, 9, 11, 13, 14, 16-19, 22, 25, 30, 33 +++ + Enterovirus 71 ++++ Rhinoviruses (many types) ++++ Colorado tick fever virus Colorado tick fever ++++ Reoviruses 2, 3 ++ ++ Rotavirus Gianotti-Crosti syndrome; infantile acute hemorrhagic edema ++++ Alphaviruses: chikungunya, Sindbis, o'nyong-nyong fever, Ross River ++ ++ Rubella virus Rubella (German measles) +++ + Flavivirus: dengue, Kunjin, West Nile Dengue, Kunjin fever ++ ++ Influenza viruses A, B ++++ Respiratory syncytial virus ++++ Parainfluenza viruses 1-4 ++++ Mumps virusMumps ++++ Measles virus Measles + +++ Hepatitis B virus ++++ Marburg virus Marburg fever ++ ++ Ebola virus Ebola hemorrhagic fever +++ + Rickettsia akari Rickettsialpox ++++ Rickettsia typhi Murine typhus +++ + Rickettsia prowazekii Epidemic typhus +++ + Rickettsia tsutsugamushi Scrub typhus +++ + Rickettsia rickettsi Rocky Mountain spotted fever ++++ Ehrlichia species Ehrlichiosis +++ + Mycoplasma pneumoniae +++ + Staphylococcus aureus (exfoliative toxin producing) Staphylococcal scarlet fever ++++ Streptococcus pyogenes Scarlet fever ++++ Arcanobacterium hemolyticum ++ ++ Neisseria meningitidis Meningococcemia ++++ Moraxella catarrhalis ++++ Listeria monocytogenes Listeriosis ++++ Streptobacillus moniliformis Rat-bite fever +++ + Yersinia pseudotuberculosis ++++ Bartonella bacilliformis Bartonellosis ++++ Brucella species Brucellosis ++++ Legionella pneumophila Legionnaires' disease ++++ Bartonella henselae Cat-scratch fever +++ + Treponema pallidum Secondary syphilis +++ + Leptospira species Leptospirosis ++++ Borrelia species Relapsing fever ++++ Coccidioides immitis Coccidioidomycosis +++ + Toxoplasma gondii Toxoplasmosis ++++ Strongyloides stercoralis Strongyloidiasis ++++ TABLE 64-10 -- Infectious Agents Associated with Illnesses in Which Vesicular Exanthems Occur Infectious Agent Illness Human parvovirus B19 Herpes simplex virus types 1 and 2 Cold sores, genital herpes, or neonatal herpes Varicella-zoster virus Chickenpox (varicella) or herpes zoster Vaccinia virus Disseminated vaccinia or eczema vaccinatum Variola virus Smallpox Monkeypox virus Orf virus Ecthyma contagiosum Tanapox virus Coxsackieviruses A4, A5, A8, A10, A16 Coxsackieviruses Bl-B3 Echoviruses 6, 9,11, 17 Enterovirus 71 Reovirus 2 Calicivirus of oceanic origin Alphaviruses: chikungunya, o'nyongnyong fever, Ross River, Sindbis Kunjin virus Mumps virus Mumps Measles virus Atypical measles Rickettsia akari Rickettsialpox Rickettsia tsutsugamushi Mycoplasma pneumoniae Streptococcus pyogenes Impetigo Pseudomonas aeruginosa Brucella species Brucellosis Bacillus anthracis Anthrax Mycobacterium tuberculosis Papulonecrotic tuberculids Candida albicans Congenital cutaneous candidiasis Leishmania braziliensis American cutaneous leishmaniasis Necator americanus Hookworm disease TABLE 64-11 -- Infectious Agents Associated with Illness in Which Petechial and Purpuric Exanthems Occur Infectious Agent Illness Human parvovirus B19 Glove and socks syndrome Varicella-zoster virus Hemorrhagic chickenpox Cytomegalovirus Congenital cytomegalovirus infection Variola virus Hemorrhagic smallpox Coxsackieviruses A4, A9 Coxsackieviruses B2-B4 Echoviruses 4, 7, 9 Colorado tick fever virus Colorado tick fever Rotavirus Alphaviruses: chikungunya, o'nyongnyong fever, Ross River, Sindbis Rubella virus Rubella (German measles) or congenital rubella Respiratory syncytial virus Measles virus Hemorrhagic (black measles) or atypical measles Lassa virus Lassa fever Marburg virus Hepatitis C virus Mixed cryoglobulinemia Hantavirus Hemorrhagic fever with renal syndrome Rickettsia typhi Murine typhus Rickettsia prowazekii Epidemic typhus Rickettsia rickettsii and other tick-borne rickettsiae Rocky Mountain spotted fever Ehrlichia species Ehrlichiosis Mycoplasma pneumoniae Streptococcus pyogenes Scarlet fever or septicemia Streptococcus pneumoniae Pneumococcal septicemia Enterococcal and viridans group streptococci Endocarditis Neisseria gonorrhoeae Gonococcemia Neisseria meningitidis Meningococcemia Moraxella catarrhalis Haemophilus influenzae H. influenzae septicemia Pseudomonas aeruginosa Ecthyma gangrenosa Streptobacillus moniliformis Yersinia pestis Septicemic plague (black death) Bartonella henselae Cat-scratch fever Treponema pallidum Congenital syphilis Borrelia species Relapsing fever Toxoplasma gondii Congenital toxoplasmosis Trichinella spiralis Trichinosis TABLE 64-12 -- Infectious Agents Associated with Illness in Which Urticarial Exanthems Occur Infectious Agent Illness Epstein-Barr virus Infectious mononucleosis Coxsackieviruses A9, A16, B4, B5 Echovirus 11 Mumps virus Mumps Hepatitis B virus Hepatitis C virus Mycoplasma pneumoniae Neisseria meningitidis Meningococcemia Shigella sonnei Shigellosis Yersinia enterocolitica Yersiniosis Borrelia burgdorferi Lyme disease Plasmodium species Malaria Coxiella burnetii Q fever Giardia lamblia Giardiasis Entamoeba histolytica Amebiasis Trichomonas vaginalis Vulvovaginalis Enterobius vermicularis Pinworm infestation Necator americanus Hookworm disease Trichinella spiralis Trichinosis Schistosoma species Schistosomiasis Trichobilharzia species Swimmer's itch or collector's itch Wuchereria bancrofti Filariasis Echinococcus species Echinococcosis Sarcoptes scabiei Scabies Trombicula irritans Chigger bites Other mites Mite bites Pediculus humanus Pediculosis Bedbugs, kissing bugs, ants, fleas, flies, and mosquitoes Bites and stings TABLE 64-13 -- Infectious Agents Associated with Papular, Nodular, and Ulcerative Lesions Agent Illness Wart virus Warts (P and N) Orf virus Ecthyma contagiosum (N) Molluscum contagiosum virus Molluscum contagiosum (P and N) Hepatitis B virus Gianotti-Crosti syndrome (P) Paravaccinia virus Milker's nodules (N) Francisella tularensis Tularemia (U) Haemophilus ducreyi Chancroid (U) Bartonella bacilliformis Bartonellosis (N) Calymmatobacterium granulomatis Granuloma inguinale (N and U) Pseudomonas aeruginosa Ecthyma gangrenosa (U) Pseudomonas folliculitis (P) Burkholderia mallei Glanders (N and U) Mycobacterium tuberculosis Lupus vulgaris (N) Papulonecrotic tuberculids (U) Atypical mycobacteria (U) Mycobacterium leprae (N) Treponema pallidum Chancre (U) Treponema pertenue Yaws (P and U) Sporotrichum schenckii Sporotrichosis (U) Blastomyces dermatitidis Blastomycosis (N and U) Fusarium species Opportunistic infection (N) Scedosporium species Opportunistic infection (N) Candida albicans Systemic candidiasis (N) Leishmania tropica Oriental sore (N and U) Leishmania braziliensis and mexicana American cutaneous leishmaniasis (P and U) Trypanosoma species Trypanosomiasis (N) Necator americanus Hookworm disease (P) Schistosoma species Schistosomiasis (P) Trichobilharzia species Swimmer's itch or collector's itch (P) Onchocerca volvulus Onchocerciasis (P) Loxosceles reclusa Recluse spider bites (U) Ticks Tick bites (U) Sarcoptes scabiei Scabies (P) Trombicula irritans Chigger bites (P) Other mites Mite bites (P) Cimex lectularius Bedbug bites (P) Triatoma sanguisuga Kissing bug bites (P and N) Solenopsis saevissima Fire ant bites (P and N) Fleas Flea bites (P) Flies and mosquitoes Fly and mosquito bites (P) N, nodular; P, papular U, ulcerative. TABLE 64-14 -- Infectious Agents Associated with Erythema Multiforme Agent Illness Human parvovirus B19 Erythema infectiosum Adenovirus 7 Respiratoryinfection Herpes simplex virus type 1 Perioral or respiratory infection Epstein-Barr virus Infectious mononucleosis Varicella virus Chickenpox Coxsackieviruses A10, A16, B5 Enterovirus syndrome Echovirus 6 Enterovirus syndrome Poliomyelitis virus Poliomyelitis Vaccinia virus Smallpox vaccination Variola virus Smallpox Orf virus Ecthyma contagiosum Paravaccinia virus Milker's nodules Influenza A virus Influenza Mumps Mumps Hepatitis B virus Serum hepatitis Chlamydia psittaci Psittacosis Chlamydia trachomatis Lymphogranuloma venereum Mycoplasma pneumoniae Respiratory symptoms Staphylococcus aureus Septicemia Streptococcus pyogenes Respiratory symptoms Neisseria gonorrhoeae Gonorrhea Corynebacterium diphtheriae Diphtheria Pseudomonas aeruginosa Septicemia Salmonella species Gastroenteritis Francisella tularensis Tularemia Yersinia species Gastrointestinal symptoms Vibrio parahaemolyticus Gastroenteritis Treponema pallidum Syphilis Bartonella henselae Cat-scratch fever Mycobacterium tuberculosis Tuberculosis Mycobacterium leprae Leprosy Coccidioides immitis Coccidioidomycosis Histoplasma capsulatum Histoplasmosis Trichomonas vaginalis Vulvovaginalis TABLE 64-15 -- Infectious Agents Associated with Erythema Nodosum Agent Illness Herpes simplex virus Perioral or respiratory infection Epstein-Barr virus Infectious mononucleosis Chlamydia psittaci Psittacosis Chlamydia trachomatis Lymphogranuloma venereum Streptococcus pyogenes Respiratory infection Neisseria meningitidis Meningococcemia Corynebacterium diphtheriae Diphtheria Campylobacter species Gastroenteritis Haemophilus ducreyi Chancroid Salmonella species Salmonellosis Yersinia species Gastrointestinal symptoms Brucella species Brucellosis Treponema pallidum Syphilis Bartonella henselae Cat-scratch fever Mycobacterium tuberculosis Tuberculosis Mycobacterium leprae Leprosy Trichophyton species Kerion of scalp Histoplasma capsulatum Histoplasmosis Cryptococcus neoformans Cryptococcosis Coccidioides immitis Coccidioidomycosis Blastomyces dermatitidis Blastomycosis Ascaris lumbricoides Roundworm infestation Wuchereria bancrofti Filariasis TABLE 64-16 -- Infectious Agents Associated with Exanthem and Meningitis Agent Illness Herpes simplex virus type 2 Recurrent genital herpes Coxsackieviruses A2, A9, B1, B4, B5 Enterovirus syndrome Echoviruses 4, 6, 9, 11, 14, 17, 25, 33 Enterovirus syndrome Colorado tick fever virus Colorado tick fever Reovirus 2 Respiratory infection West Nile virus Meningoencephalitis Neisseria meningitidis Meningococcemia Borrelia burgdorferi Lyme disease Listeria monocytogenes Listeriosis Toxoplasma gondii Toxoplasmosis TABLE 64-17 -- Infectious Agents Associated with Exanthem and Pulmonary Involvement Agent Illness Adenoviruses 7,7a Respiratory infection Herpes simplex virus type 1 Respiratory infection Varicella-zoster virus Chickenpox pneumonia Epstein-Barr virus Infectious mononucleosis Coxsackievirus A9 Enterovirus syndrome Echovirus 11 Enterovirus syndrome Reovirus 3 Respiratory infection Measles virus Measles pneumonia and atypical measles Chlamydia psittaci Psittacosis Mycoplasma pneumoniae M. pneumoniae pneumonia Neisseria meningitidis Meningococcal pneumonia Mycobacterium tuberculosis Tuberculosis Histoplasma capsulatum Histoplasmosis Cryptococcus neoformans Cryptococcosis Coccidioides immitis Coccidioidomycosis ERYTHEMATOUS MACULAR EXANTHEMS When all infectious diseases with exanthems are taken into consideration, the occurrence of illnesses in which the lesions are just macular is rare. However, many important, severe diseases have a transitory erythematous macular rash early in their course, and recognition of this fact can be lifesaving. Infectious agents associated with illnesses in which macular exanthems have been observed are presented in Table 64-8. The most common rash in infectious mononucleosis is erythematous and maculopapular, but rarely (most often in association with the administration of ampicillin) the exanthem is generalized, confluent, fiery red, and macular. Blotchy or diffuse erythematous macular rashes have been caused specifically by 12 different enterovirus types. Most of these descriptions involve neonates, other very young infants, and adults; children in the peak ages for enteroviral exanthematous diseases do not seem to have solely macular lesions. In neonates, enteroviral disease with a blotchy macular rash in association with fever and lethargy usually is confused with bacterial sepsis. Patients with dengue, Lassa, and Marburg viral infections frequently have a macular, flushed appearance before other cutaneous manifestations develop. Similarly, in both murine and epidemic typhus, the initial skin manifestations are macular but progress rapidly to more pronounced findings. Bacterial septicemia with both common and exotic organisms is associated frequently with a generalized flush. In staphylococcal disease, the rash is particularly apparent in endocarditis and osteomyelitis. The most famous disease with a macular rash is typhoid fever. Rose spots occur most commonly on the abdomen, but they also are seen on the chest and back. They are erythematous, macular lesions 2 to 4 mm in size. Lesions likewise have been noted in leptospirosis and psittacosis. In addition, rose spots are seen occasionally in septicemic illnesses caused by other Salmonella spp. The slapped-cheek appearance in erythema infectiosum (Fig. 64-6) is caused by an erythematous macular flush of the cheeks. The full-blown rash in streptococcal scarlet fever is maculopapular, but frequently in mild cases and in those altered by antibiotic therapy, the exanthem is only macular in character (scarlatina). ERYTHEMATOUS MACULOPAPULAR EXANTHEMS An erythematous maculopapular rash is the most common cutaneous manifestation of systemic infection (Figs. 64-2, 64-8, 64-10, and 64-13). It also is an exceedingly common occurrence in allergic conditions. However, all too frequently, the rash of an infectious illness is ascribed to an allergic reaction to an administered drug rather than correctly to the disease process. The converse—an allergic rash illness that is attributed mistakenly to an infectious agent—rarely occurs. Infectious agents associated with illnesses in which maculopapular exanthems occur are presented in Table 64-9. Both by the number of possible etiologic agents and by total infections, viruses account for the vast majority of illnesses with maculopapular eruptions. Although the distribution and progression of rashes are important aspects relating to the differential diagnosis, the single most important point is whether the lesions are discrete (rubelliform) or confluent (morbilliform). Adenoviruses are not uncommon causes of erythematous maculopapular eruptions. In most instances, signs and symptoms of upper respiratory infection are present. Most commonly, the lesions are discrete, but occasionally, a confluent morbilliform rash is present. A roseola infantum picture—occurrence of rash after the fever falls by crisis—frequently occurs. As a rule, the exanthem in adenoviral infections starts on the head and spreads to the trunk and extremities. Enteroviruses account for the greatest number of erythematous maculopapular rash illnesses; 36 different serologic types have been implicated. The enteroviral types most commonly associated with maculopapular exanthems are coxsackieviruses A9 and B5 and echoviruses 4, 9, and 16. Echovirus 9 has been the most frequent cause of enteroviralexanthem for the last 35 years (Fig. 64-13). Although morbilliform rashes do occur, the more usual cutaneous manifestation is one suggestive of rubella. The exanthem usually starts on the head and upper part of the trunk and spreads to the extremities. Although they are not common manifestations of respiratory viruses (rhinoviruses, influenza A and B viruses, RSV, and parainfluenza viruses types 1 through 4), exanthems probably occur more often than is generally realized. Because children infected with these agents frequently are given antibiotics, confusion often occurs between an allergic and an infectious etiology. With all the respiratory viruses, the signs and symptoms of respiratory illness (cough, coryza, croup, bronchiolitis, and so on) are prominent. The exanthems virtually are always discrete and rubelliform in character. In dengue, the exanthem goes through several stages. Initially, it is macular, then erythematous maculopapular, and finally hemorrhagic. Similarly, the exanthems in the rickettsial diseases go through stages that vary in relation to the specific agent (see Table 64-2). In Rocky Mountain spotted fever, the rash starts on the distal ends of extremities. Although the hallmark of meningococcemia is a petechial or purpuric rash, in the initial stages, the exanthem may be erythematous and maculopapular. In addition, maculopapular eruptions are observed in chronic meningococcemia. The most notable cutaneous lesion in coccidioidomycosis is erythema nodosum, but a rubelliform rash early in infection is not an unusual manifestation. VESICULAR EXANTHEMS The three main categories of vesicular exanthems are single or localized lesions, generalized lesions in greatest concentration on the trunk and head, and generalized lesions with the greatest concentration on the extremities (Figs. 64-4, 64-5, and 64-9). Infectious agents associated with illnesses in which vesicular rashes develop are presented in Table 64-10. The exanthem in primary or recurrent HSV infection is localized, as it is in recurrent endogenous varicella-zoster infection (herpes zoster), ecthyma contagiosum, tanapox, scrub typhus, anthrax, and papulonecrotic tuberculids (Fig. 64-5). The vesicular exanthematous disease that occurs most commonly in children today is chickenpox (Fig. 65-4). It should be a readily recognizable disease, but is all too frequently confused with enteroviral infections or insect bites and allergic conditions. Chickenpox has a long incubation period (16 days) and is associated with mild fever and an exanthem that starts on the head and upper part of the trunk and spreads to the extremities. The rash always is more prominent on the trunk than on the extremities. At any time during the first few days of the rash, lesions in all stages (macules, papules, and vesicles) can be seen. Individual lesions in chickenpox form scabs that persist for approximately 7 days. In contrast to that of chickenpox, the exanthem in enteroviral infections frequently is peripheral in distribution, and the lesions generally heal without scabs. The incubation period (5 days) is much shorter than that of chickenpox. The hand, foot, and mouth syndrome is a common manifestation of enteroviral vesicular rash illnesses (Figs. 64-9 to 64-11). The most frequent etiologic agent in the hand, foot, and mouth syndrome is coxsackievirus A16, but the syndrome also has been attributed to coxsackieviruses A5, A9, A10, B1, and B3 and enterovirus 71. Enteroviral infections with vesicular exanthems in which the hand, foot, and mouth distribution is not present quite frequently are diagnosed erroneously as insect bites or poison ivy. PETECHIAL AND PURPURIC EXANTHEMS A large number of infectious agents are associated with petechial and purpuric skin manifestations (Figs. 64-14 and 64-15). They are listed in Table 64-11. Infectious diseases with hemorrhagic rash can be fulminant fatal events or relatively benign illnesses. On a worldwide basis, meningococcemia is perhaps the most important and feared, although it is not the most prevalent of the petechial and purpuric exanthematous diseases. The relatively sudden onset of fever and a petechial rash must be considered and treated as meningococcemia unless another etiology can be established with absolute certainty. The most important of the differential diagnostic problems is exanthem caused by enteroviral infection. Many different entero-virus illnesses have a sudden onset with accompanying fever and petechial rash. In addition, the situation frequently is complicated further by the occurrence of meningitis. The most important enterovirus in its ability to mimic meningococcemia is echovirus 9. Purpuric and petechial lesions in infectious illnesses can result from a direct or indirect (immunologic) effect of the infectious agent at the cutaneous site or from the occurrence of throm-bocytopenia. Thrombocytopenia is noted most commonly in acquired rubella virus infections. URTICARIAL EXANTHEMS The occurrence of urticaria all too frequently leads the physician to suspect an allergic or dermatologic condition (Figs. 64-12 and 64-16).[199,][200] However, what has become quite evident in recent years is that when urticaria develops in association with an acute febrile illness, the cutaneous reaction is a direct effect of an infectious agent, and its mediation does not require an allergic response. Listed in Table 64-12 are infectious agents associated with urticarial exanthems. Papular urticaria occurs very commonly in children in the summer and fall and most frequently is the result of insect bites (see Table 64-6). However, virtually identical lesions occur in infections with coxsackievirus A as well as with other enteroviruses (Fig. 64-12). The main point for differentiation is that fever regularly develops in the virus-induced exanthems but is not a characteristic associated with insect bites. Early in the course of meningococcemia, the exanthem can be urticarial, so an illness of sudden onset with fever and this cutaneous manifestation never should be taken lightly. PAPULAR, NODULAR, AND ULCERATIVE LESIONS In many instances, the lesions in this category occur as single events at the site of primary inoculation. Specific illnesses and etiologic agents are listed in Table 64-13. DISTINCTIVE CLINICAL FEATURES OR SYNDROMES (Figs. 64-19 to 64-24) Erythema Multiforme Erythema multiforme is a self-limited skin eruption that is erythematous and characterized by distinctive target or iris lesions or both. Small vesicles and urticarial areas also may develop. On occasion, the disease is severe and associated with mucosal involvement and genital lesions. In this latter illness—the Stevens-Johnson syndrome, bullous erythema multiforme, erythema multiforme exudativum major—severe ulcerative, oral, and genital lesions occur; generalized exanthems become bullous, and conjunctivitis is present. The illness is associated with fever and general distress. Although the pathogenesis of erythema multiforme is unknown, what is clear is that multiple factors, including infectious agents, are responsible for its occurrence. Infectious agents associated with erythema multiforme are listed in Table 64-14. The single most important infectious cause of erythema multiforme and Stevens-Johnson syndrome is M. pneumoniae. When M. pneumoniae is the instigating agent, the patient nearly always has concomitant pneumonia. HSV frequently has been recovered from the throats of persons with erythema multiforme, but the cause-and-effect relationship in many cases must be questioned. However, in a recent study, HSV DNA was found in the skin lesions of 11 of 31 patients with erythema multiforme.[58] Erythema Nodosum Erythema nodosum most commonly occurs on the anterior aspect of the lower part of the legs but may be seen anywhere on the body. The lesions are raised, erythematous, and painful to touch. Their usual size is approximately 2 to 4 cm, with a duration of 2 to 6 weeks. Erythema nodosum occursless commonly today than it did 4 decades ago, and the frequency of specific associated infectious agents also is different. In the past, streptococcal and mycobacterial infections were the agents most commonly related. Now, the exanthem most often is associated with respiratory infection with Histoplasma capsulatum, Cryptococcus neoformans, and Coccidioides immitis. Infectious agents associated with erythema nodosum are listed in Table 64-15. Hand, Foot, and Mouth Syndrome The hand, foot, and mouth syndrome is a clearly recognizable viral illness characterized by vesicular lesions in the anterior of the mouth and on the hands and feet in association with fever. Although several enteroviruses (coxsackieviruses A5, A9, A10, A16, B1, and B3 and enterovirus 71) have been implicated, as have HSV and foot and mouth disease virus, most of these cases are caused by coxsackievirus A16. Roseola-like Illness Roseola infantum is a classic pediatric illness characterized by fever of 3 to 5 days' duration, rapid defervescence, and then the appearance of an erythematous macular or maculopapular rash that persists for 1 to 2 days. Roseola is an age-related response to infection with many viruses. Recent studies suggest that a leading cause of roseola infantum is primary infection with HHV-6. The following other viruses have been noted in association with roseola: adenoviruses 1, 2, 3, and 14; coxsackieviruses A6, A9, B1, B2, B4, and B5; echoviruses 9, 11, 16, 25, 27, and 30; parainfluenza virus type 1; and measles vaccine virus. Rocky Mountain Spotted Fever–like Illness Rocky Mountain spotted fever is a clinical illness characterized by fever and a petechial rash located mainly on the distal ends of extremities. The illness is caused by Rickettsia rickettsii and is prevalent in many areas of North America; the infectious agent is transmitted to humans by ticks. In other areas of the world, other tick-borne rickettsiae (Rickettsia sibirica, Rickettsia australis, Rickettsia conorii) produce similar human illness. Infection with Ehrlichia canis also can cause an illness similar to Rocky Mountain spotted fever. The most important illness confused with Rocky Mountain spotted fever is atypical measles (see Chapter 192). This illness, which has both the constitutional symptoms of Rocky Mountain spotted fever and a rash most prominent on the extremities, occurs almost exclusively after exposure to measles virus in some persons previously immunized with inactivated (killed) measles vaccine. Rat-bite fever caused by S. moniliformis also has been misdiagnosed as Rocky Mountain spotted fever.[156] Exanthem and Meningitis Aseptic and also bacterial meningitis frequently are characterized by both exanthem and symptoms and signs of neurologic involvement. Infectious agents associated with exanthem and meningitis are presented in Table 64-16. Of most importance in this category is the differential diagnosis of enteroviral syndromes and meningococcemia. Exanthem and Pulmonary Involvement Infectious agents associated with exanthem and pulmonary involvement are listed in Table 64-17. In patients older than 5 years old, the leading cause of exanthem and pneumonia is M. pneumoniae infection. In younger children, adenoviruses are the most important etiologic agents. With the exception of enteroviral infections, which are more likely to involve young children, most of the illnesses listed in Table 64-17 occur in older children and young adults. Gianotti-Crosti Syndrome (Papular Acrodermatitis) Gianotti-Crosti syndrome is a distinct clinical entity characterized by a papular (lichenoid) exanthem, generalized lymphadenopathy, hepatomegaly, and acute anicteric hepatitis.[46,][170,][173] In most instances, this illness has been associated with hepatitis B virus infection. The syndrome also has been noted in association with Epstein-Barr virus, cytomegalovirus, coxsackievirus B virus, and RSV infections.[65,][111,][171,][193] Cutaneous Manifestations Associated with Infections in Immunocompromised Patients Copyright © All infectious agents that cause exanthems in immunologically normal children can cause infections in immunocompromised children. However, the clinical manifestations may be different. For example, measles virus infection in a child who is T-cell-deficient may be associated with a severe, progressive pneumonia but not the typical rash. Other viral exanthems that are self-limited in normal children, such as varicella, may be progressive and develop into hemorrhagic skin lesions with disseminated organ involvement in children with T-cell-deficiency. Of particular concern are bacterial and fungal infections, which are rarely a problem in normal children but are rapidly fatal in granulocytopenic children. These patients have characteristic skin lesions resulting from disseminated infections. Of importance are ecthyma gangrenosa resulting from Pseudomonas aeruginosa septicemia and the nodular and purpuric lesions of disseminated fungal infections caused by Aspergillus, Candida, and other less common agents. DIAGNOSIS DIFFERENTIAL DIAGNOSIS The diagnosis of infectious exanthems frequently is considered an impossible task by many physicians. Other physicians glibly call the first maculopapular exanthem of childhood “roseola” and the first vesicular rash “chickenpox” without consideration of more appropriate choices. The hallmark of diagnosis in exanthematous disease is careful elicitation of historic data. Differential diagnosis requires the consideration of noninfectious etiologies as well as different infectious agents. Listed in Table 64-18 are the major considerations in the diagnosis of diseases with cutaneous manifestations. TABLE 64-18 -- Important Aspects in the Diagnosis of Exanthematous Illness Exposure Season Incubation period Age Previous exanthems Relationship of rash to fever Adenopathy Types of Rash Distribution of rash Progression of rash Exanthem Other associated symptoms Laboratory tests From Cherry, J. D.: Newer viral exanthems. Adv. Pediatr. 16:233-286, 1969. A history of exposure is most important in making a differential diagnosis. For example, was the patient exposed to poison ivy, insects, or a person ill with a specific disease? In infectious illnesses with high clinical expression rates (measles, chickenpox, rubella), proper questioning usually reveals a contact case or at least other cases in the community. On the other hand, in illnesses with low rates of clinical expression of exanthem, such as adenoviral and some enteroviral infections, the source may not be apparent. Consideration of the seasonal occurrence of different infectious agents, as well as insects, is particularly useful in making a differential diagnosis. In temperate climates, enteroviral and arthropod-mediated diseases occur in the summer and fall. Exanthems with measles, varicella-zoster, and rubella viruses occur most often in the winter and spring. The diagnosis of rubella is important because of fetal consequences. All too frequently, rubella is overdiagnosed and underdiagnosed, both of which can be avoided if its seasonal prevalence is understood. The incubation period is important in separating the exanthem caused by rubella, varicella-zoster, or measles viruses from rash illnesses caused by enteroviruses or common respiratory viruses. The former have long incubation periods, whereas in the others, the period from exposure to the onset of illness is less than 1 week. Age can be useful. Today in the United States, measles and rubella often are illnesses of adolescents and young adults. Enteroviral exanthem frequency is related inversely to age. Questioning to obtain a pertinent history of previous exanthems can give useful information if it is done with care. For example, if patients are asked whether they had rubella, the answer is quite unreliable. However,if the past illness is documented by year, season, and symptoms, accurate information often is obtained. The relationship of rash to fever is most significant in the diagnosis of roseola. The presence or absence of fever is important in separating exanthems of infectious and noninfectious etiology. Frequently, insect bites are diagnosed as chickenpox by parents and physicians as well. Chickenpox rarely occurs without fever. The type and distribution of exanthem obviously are important. They virtually are diagnostic in hand, foot, and mouth syndrome, Rocky Mountain spotted fever, and atypical measles. Enanthem can lead to a specific diagnosis (Koplik spots in measles [Fig. 64-1]) or a category diagnosis (herpangina in enteroviral infections). Other characteristics, such as those listed in Tables 64-8 through 64-17, obviously are useful in delineating a specific illness. SPECIFIC DIAGNOSIS As with other infectious diseases, establishing specific diagnosis depends on the acquisition of proper cultures, serologic tests, and microscopic study of secretions or histologic or cytologic pre-parations. These techniques are discussed in other chapters of this book. Vesicular lesions always should be scraped for cytologic study or direct antigen identification (varicella, herpes simplex), and, frequently, petechial lesions should be scraped and stained in a search for infectious agents (meningococci). The etiology of viral infections can be established by isolation of virus, direct antigen detection, or serologic methods. In most instances, a virus recovered from the throat indicates acute infection and is the probable cause of a particular illness. Serologic study without culture is useful in diagnosing rickettsial diseases, some viral infections, and a few illnesses of bacterial origin. Serologic study without virus isolation generally is not useful in diagnosing enteroviral illnesses. TREATMENT, PROGNOSIS, AND PREVENTION The treatment, prognosis, and prevention of exanthematous diseases are presented in appropriate chapters throughout this text. Figure 64-1 Measles - Koplik spots with involvement of the buccal and lower labial mucosa. Figure 64-2 Measles exanthem. Note the generalized erythematous confluent base supporting small papular and microvesicular lesions. Figure 64-3 Rubella exanthem. The rash is erythematous, maculopapular, and discrete. Figure 64-4 Chickenpox exanthem. Typical lesions in all stages: vesicles, papulovesicles, and papules. Figure 64-5 Primary herpes simplex virus infection in an infant. Note the severe stomatitis and papulovesicular and vesicular lesions under the lower lip and on the cheek. Figure 64-6 Slapped-cheek appearance with a relative circumoral maculopapular rash in erythema infectiosum. Figure 64-7 Rash with a lacelike, or reticular, pattern in erythema infectiosum. Figure 64-8 Confluent exanthem in a patient with human parvovirus infection. Figure 64-11 Two large ulcerative lesions on the underside of the tongue in a patient with hand, foot, and mouth syndrome caused by coxsackievirus A16. Figure 64-12 Papular-urticarial lesions in coxsackievirus A9 infection. Figure 64-13 Erythematous, discrete, maculopapular, and petechial rash of echovirus 9 infection. Figure 64-14 Petechial and purpuric rash in a child with coxsackievirus A9 infection. Figure 64-15 Erythematous, papular, papulovesicular, and petechial lesions suggestive of anaphylactic purpura in a child with coxsackievirus A4 infection. Figure 64-16 Acute urticaria in a child with hand, foot, and mouth syndrome caused by coxsackievirus A16 infection. Figure 64-17 Bullous impetigo in a newborn infant caused by exfoliative toxin–producing Staphylococcus aureus. Figure 64-18 Scalded skin syndrome caused by exfoliative toxin–producing Staphylococcus aureus. Figure 64-20 Numerous flat-topped and dome-shaped, slightly erythematous papules over the skin of the perineum of a young girl with bowenoid papulosis Figure 64-21 Numerous isolated purple papules of dermal erythropoiesis overlying the icteric skin of a neonate with congenital cytomegalovirus infection. Figure 64-22 Tinea pedis. Peeling, macerations, and fissuring in the fourth interdigital space of the foot are characteristic of dermatophytic infections. Figure 64-23 Clinical photograph of an infant with Candida diaper dermatitis. Confluent and discrete erythematous papules and plaques involving the scrotum, penis, and suprapubic and inguinal area are evident. Figure 64-24 An extensive crusted erosion on the left thigh of a child with a cryptococcal skin infection.
Mais conteúdos dessa disciplina
Captura de Tela 2024-03-21 as 17 40 41- primoBasilio
- instintoNacionalidade
- contituinteSombraLuz
- bv000257
- bv000189
- Revista Teatros
- updateOrder 0 0 1 2 0 0 1 2 0 1 0 0 1 2 0 0 0 0 0 0 0 0 0 1 0 0 1 1 0 0
- updateOrder 0 0 1 2 0 0 1 2 0 1 0
- bv000257
- O missionário, Inglês de Sousa
- A Cartomante, Machado de Assis
- 2- C.O. 3 -Tipos de coerencia [2] nome do livro
- Aparelho Fonador
Conteúdos escolhidos para você
Perguntas dessa disciplina
Mais conteúdos dessa disciplina
- Captura de Tela 2024-03-21 as 17 40 41
- primoBasilio
- instintoNacionalidade
- contituinteSombraLuz
- bv000257
- bv000189
- Revista Teatros
- updateOrder 0 0 1 2 0 0 1 2 0 1 0 0 1 2 0 0 0 0 0 0 0 0 0 1 0 0 1 1 0 0
- updateOrder 0 0 1 2 0 0 1 2 0 1 0
- bv000257
- O missionário, Inglês de Sousa
- A Cartomante, Machado de Assis
- 2- C.O. 3 -Tipos de coerencia [2] nome do livro
- Aparelho Fonador
