Pediatric Exanthems Sarah Stein, MD Sections of Dermatology and Pediatrics University of Chicago Definitions • Exanthem: A skin eruption occurring as a symptom of a general disease. • Enanthem: Eruptive lesions on the mucous membranes. “Classic Childhood Exanthems” I. II. III. IV. V. VI. Measles (Rubeola) Scarlet Fever Rubella (German measles) Filatow-Dukes Disease Erythema Infectiosum Roseola Infantum “1st Disease”=Measles • Paramyxovirus • At risk: preschool-age children who escaped vaccination; school-age children/adolescents in whom vaccination failed • Season: late winter/spring • Incubation period: 8-12days • Infectious period: 1-2d before prodrome to 4d after onset of rash Measles: clinical features • Prodrome: day 7-11 after exposure – Fever, cough, coryza, conjunctivitis • Enanthem: Koplik’s spots appear 2 days before the rash, last 2 days into the rash Measles: “morbilliform exanthem” Presents day 14 after exposure Measles: complications • • • • • • Otitis media Bronchopneumonia Encephalitis Myocarditis Pericarditis Subacute sclerosing panencephalitis—late sequellae due to persistent infx of the CNS “2nd Disease”=Scarlet Fever • Due to erythrogenic exotoxin-producing group A beta-hemolytic streptococci • At risk: <10yo, peak 4-8yo • Season: late fall, winter, spring – Likely due to close contact indoors in school • Incubation period: 2-4 days • Infectious period: during acute infection, gradually diminishes over weeks Scarlet Fever: clinical features • Abrupt onset fever, headache, vomiting, malaise, sore throat • Enanthem – Bright red oral mucosa – Palatal petechiae – Tongue changes Strawberry tongues Scarlet Fever: exanthem (12-48hrs after fever onset) Scarlet Fever: complications • Purulent complications – Otitis media – Sinusitis – Peritonsillar/retropharyngeal abscesses – Cervical adenitis • Nonsuppurative sequalae – Rheumatic fever – Acute glomerulonephritis Scarlet Fever and a negative strep culture? • Scarlet fever-like syndrome in a young adult • Arcanobacterium haemolyticum (aka corynibacterium haemolyticum) – Gram positive rod – Grows on 5% human blood agar – More sensitive to erythromycin “3rd Disease”=Rubella • • • • • Togavirus At risk: unvaccinated adolescents Season: late winter/early spring Incubation period: 14-21 days Infectious period: 5-7d before rash to 3-5d after rash Rubella: clinical features • Asymptomatic infection in up to 50% • Prodrome – Children: absent to mild – Adol and Adult: Fever, malaise, sore throat, nausea, anorexia, painful occipital LAD • Enanthem – Forschheimer’s spots = petechiae on the hard palate Rubella: exanthem Rubella: complications • Arthralgias/arthritis in older patients • Peripheral neuritis, encephalitis, thrombocytopenic purpura—rare • Congenital rubella syndrome – Infection during first trimester – IUGR, eye findings, deafness, cardiac defects, anemia, thrombocytopenia, skin nodules “4th Disease”=Filatow-Dukes Disease • Obsolete • Probably now better defined as another clinical entity “5th Disease”=Erythema Infectiosum • • • • • Human Parvovirus B19 At risk: school-age children Season: sporadic Incubation period: 4-14 days Infectious period: up until onset of the rash EI: clinical features • Over 50% of infections are asymptomatic • Prodrome – Mild fever (15-30%), sore throat, malaise • Adults—flu-like symptoms, arthralgias/arthritis (potentially chronic), rash in up to 40% • Hematological changes–proerythrocyte tropic virus – Drop in RBC count Erythema Infectiosum: slapped cheek appearance EI: complications • Immunocompromised—chronic infection with severe, persistent, relapsing and remitting anemia, prolonged viral shedding • Patients with decreased RBC survival time (hemoglobinopathies, hemolytic dis)— aplastic crises, prolonged viral shedding • Fetal infection—hydrops fetalis (overall risk of fetal death 1-9%) Papular purpuric glove and sock syndrome • 2nd syndrome ascribed to Parvovirus B19, other viruses may be possible causes • Spring/summer; young adults • Rash, LAD, fever, anorexia, arthralgias • Self-limited over 7-14 days • Viremia clears after rash Papular purpuric glove and sock syndrome th “6 Disease”=Roseola infantum (aka Exanthem subitum) • • • • • Human Herpes Virus 6 (and 7) At risk: 6-36 mo (peak age 6-7mo) Season: sporadic Incubation period: 9 days Infectious period: virus is intermittantly shed into saliva throughout life; asymp persistent infection Roseola: clinical features • High fever for 3-4 days • Abrupt defervescence with appearance of rash • Associated seizures likely due to infection of the meninges by the virus Roseola: exanthem The rest of the herpes family • • • • • • Herpes simplex virus 1 and 2 Varicella-zoster virus Cytomegalovirus Epstein-Barr virus Human Herpes virus 6 and 7 Human Herpes virus 8 Chicken Pox=Varicella • Varicella zoster virus, family herpesviridae • At risk: young children, nonimmune inds – Second attack rate within households is 80-95% • Season: sporadic • Incubation period: 10-21 days • Infectious period: via resp drop and vesicle fluid, 2d before to 5d after onset of rash Chicken Pox: clinical features • Prodrome – Ranges from asymp to fever, malaise, cough, coryza, sore throat • Pruritus – Variable from mild to severe Chicken Pox: exanthem Chicken Pox: complications • Secondary bacterial infection—5-10% • Otitis media—5% • Higher risk for adults, neonates, immunocomp. – – – – Pneumonitis Encephalitis Cerebellar ataxia Hepatitis • Other rare comps—Reye syn, Guillain-Barre, nephritis, carditis, arthritis, orchitis, uveitis Smallpox (variola): exanthem Herpes Zoster: clinical features • Reactivation of latent VZV in sensory ganglia • At risk: elderly, immunocomp., children who had chicken pox in utero or in 1st year • Prodrome – Unusual in children – In adults, dull ache for up to a week before rash Varicella Zoster: exanthem Cephalic herpes zoster: RamseyHunt Syndrome Varicella Zoster: complications • Post-herpetic neuralgia—uncommon in kids • Disseminated dis—immunocompromised – Widespread cutaneous lesions – Visceral disease • Ulcerations • Secondary infection Infectious Mononucleosis Infectious Mononucleosis: and ampicillin/amoxicillin Enterovirus rashes • Hand-foot-mouth disease • Herpangina • Nonspecific eruptions Hand-foot-mouth disease • Typically due to Coxsackie A16 • At risk: preschool-school aged children – Highly contagious • Incubation period: 4-6 days • Prodrome: 1-2 days before rash – Low-grade fever, anorexia, malaise, sore mouth HFMD: enanthem HFMD: exanthem Nail matrix arrest and HFMD Herpangina • Coxsackie A viruses • At risk: young children • Prodrome – Fever, sore throat Herpangina: enanthem Nonspecific enteroviral exanthems • Multitude of presentations – – – – Morbilliform or rubelliform Vesicular Petechial (typical of echovirus 9) Urticarial • Involvement of other systems-rare, but not to be ignored – CNS, pulmonary, GI, muscular, cardiac Enterovirus: nonspecific exanthem “Named” exanthems • Gianotti-Crosti Syndrome, aka papular acrodermatitis of childhood • Unilateral Laterothoracic Exanthem, aka asymmetric periflexural exanthem of childhood (APEC) • Pityriais Rosea Gianotti-Crosti syndrome: clinical features • Most often due to EBV, also Hep B and all other viruses • At risk: 6mo-14yrs, mean 2yrs • Season: spring and early summer • Constitutional symptoms: mild – Low grade fever, malaise, LAD, rare pruritus, mild hepatitis (except in Hep B-associated case) Gianotti-Crosti Syndrome Gianotti-Crosti Syndrome Gianotti-Crosti Syndrome Unilateral Laterothoracic Exanthem • aka Asymmetric Periflexural Exanthem • ?viral: suggested by age, clustering, resp symptoms • At risk: 1-5yos, mean 2yo • Prodrome: 60-75% – Rhinitis, pharyngitis, bronchitis, conjunctivitis, gastroenteritis – Fever in 40-65% Unilateral Laterothoracic Exanthem Pityriasis Rosea • ?viral: suggested by seasonality, mild prodromal symptoms, assoc URI, clustering of cases • Season: spring, autumn, winter • At risk: 10-35yos, can be seen in younger • Prodrome: very mild, if any – Malaise, nausea, anorexia, headache, low fever Pityriasis Rosea Pityriasis Rosea Pityriasis Rosea