Some Causes of Rash in Infants and Children
Cause | Suggestive Findings | Diagnostic Approach |
|---|---|---|
Infections | ||
Candidal infections | Beefy red rash with adjacent satellite lesions in the diaper area, including skin creases Often fluffy white plaques on the tongue or oral mucosa Sometimes history of recent antibiotic use | Clinical evaluation Sometimes scrapings of lesions for potassium hydroxide wet mount |
Red dots on the face, scalp, torso and proximal extremities that progress over 10–12 hours to small bumps, vesicles, and then umbilicated pustules, which form crusts Intensely itchy blisters, which may also occur on the palms, soles, scalp, and mucous membranes, as well as in the diaper area | Clinical evaluation | |
Confluent erythema on cheeks (slapped-cheek appearance) Sometimes fever, malaise | Clinical evaluation | |
Nonbullous impetigo: Painless but itchy red sore near the nose or mouth that soon leaks pus or fluid and forms a honey-colored scab Bullous impetigo: Occurs mainly in children < 2 years Painless, fluid-filled blisters—mostly on the arms, legs, and trunk, surrounded by red and itchy skin—which, after breaking, form yellow or silvery scabs | Clinical evaluation | |
Erythema migrans rash; an enlarging (to about 5–7 cm) erythematous lesion sometimes with central clearing or rarely purpura (2%) Often fatigue, headache, joint or body aches Usually in endemic area with risk of exposure to ticks, with or without a known tick bite | Clinical evaluation Sometimes serologic testing | |
Maculopapular rash beginning on the face and spreading to the trunk and extremities Often Koplik spots (white spots on buccal mucosa) Fever, cough, coryza, conjunctival injection | Clinical evaluation Serologic testing (for public health reasons) | |
Petechial rash, sometimes with purpura fulminans Fever, lethargy, irritability In older children, meningeal signs Tachycardia, sometimes hypotension | Gram stain and culture of blood and cerebrospinal fluid | |
Clusters of flesh-colored, umbilicated papules No itching or discomfort | Clinical evaluation | |
Maculopapular rash that appears suddenly after 4 or 5 days of high fever, typically as fever resolves | Clinical evaluation | |
Sometimes itchy rash that begins on the face and spreads downward, appears as pink or light red spots (which may merge to form evenly colored patches), and usually clears on the face as it spreads Lasts up to 3 days Often lymphadenopathy (occipital, postauricular, posterior cervical), mild fever | Clinical evaluation Serologic testing (for public health reasons) | |
Scarlet fever (scarlatina) | Fever, sometimes sore throat Generalized fine, red, rough-textured, blanching rash that typically appears 12–72 hours after the fever and starts on the chest, in the armpits, and on the groin Characteristic pale area around the mouth (circumoral pallor) and accentuation in the skinfolds (Pastia lines), strawberry tongue Often followed by extensive desquamation of the palms and soles, tips of fingers and toes, and groin | Clinical evaluation Sometimes rapid streptococcal assay or throat culture |
Widespread areas of painful erythema that develop large, flaccid blisters, which are easily ruptured, leaving large areas of desquamation Lateral extension of blisters with gentle pressure (positive Nikolsky sign) Spares the mucous membranes Usually in children < 5 years | Clinical evaluation Sometimes confirmed by biopsy and/or cultures | |
Scaly, oval lesions with a slightly raised border and central clearing Mild itching | Clinical evaluation Sometimes scrapings of lesions for potassium hydroxide wet mount | |
Viral infection (systemic) | Maculopapular rash Often viral respiratory prodrome | Clinical evaluation |
Hypersensitivity reactions | ||
Atopic dermatitis (eczema) | Chronic or recurrent red, scaly patches, often in flexor creases Sometimes family history | Clinical evaluation |
Intensely itchy erythema, sometimes with vesicles No systemic manifestations | Clinical evaluation | |
Diffuse maculopapular rash History of current or recent (within 1 week) drug use | Clinical evaluation | |
Prodrome of fever, malaise, cough, sore throat, and conjunctivitis Painful mucosal ulcers, almost always in the mouth and lips but sometimes in the genital and anal regions Widespread areas of painful erythema that develop large, flaccid blisters, which are easily ruptured, leaving large areas of desquamation; possibly affecting the soles but usually not the scalp Lateral extension of blisters with gentle pressure (positive Nikolsky sign) Sometimes use of a causative drug (eg, sulfonamides, penicillins, anticonvulsants) | Clinical evaluation Sometimes biopsy | |
Well-circumscribed, pruritic, red, raised lesions With or without history of exposure to known or potential allergens | Clinical evaluation | |
Vasculitides | ||
Immunoglobulin A–associated vasculitis (formerly called Henoch-Schönlein purpura) | Palpable purpura appearing in crops over days to weeks, typically in dependent areas (eg, legs, buttocks) Often arthritis, abdominal pain Sometimes hematuria, heme-positive stool, and/or intussusception Usually in children < 10 years | Clinical evaluation Sometimes skin biopsy |
Diffuse erythematous maculopapular rash that can vary in appearance (eg, urticarial, target-like, purpuric) but never bullous or vesicular; may involve the palms and/or soles Fever (often > 39° C) for > 5 days Red, cracked lips, strawberry tongue, conjunctivitis, cervical lymphadenopathy Edema of hands and feet Later desquamation of fingers and toes extending to palms and soles | Clinical criteria Testing to exclude other disorders | |
Other | ||
Red and yellow scaling on the scalp (cradle cap) and sometimes in skinfolds | Clinical evaluation | |
Diaper rash (noncandidal) | Bright red rash in the diaper area, sparing creases | Clinical evaluation |
Petechial rash, pallor Usually during or after infectious colitis manifesting with abdominal pain, vomiting, and bloody diarrhea Oliguria or anuria Hypertension | Complete blood count with platelets and peripheral smear to check for evidence of microangiopathic anemia and thrombocytopenia Renal function tests Stool testing (Shiga toxin assay or specific culture for E. coli O157:H7) | |
Small pearly cysts on a neonate's face | Clinical evaluation | |
Pink-red blotches, symmetrically arranged and starting on the extremities, then evolving into the classic target-like lesion with a pink-red ring around a pale center Sometimes oral mucosal lesions, pruritis | Clinical evaluation | |
Miliaria (heat rash) | Small red bumps or occasionally small blisters Most common in very young children but can occur at any age, particularly during hot and humid weather | Clinical evaluation |
Erythema toxicum | Flat red splotches (usually with a white, pimple-like bump in the middle), which appear in up to half of all babies Rarely appears after 5 days of age and is usually gone in 7–14 days | Clinical evaluation |
Neonatal acne | Red bumps, sometimes with white dots in the center on a neonate's face Usually occurs between 2 and 4 weeks after birth but may appear up to 4 months after birth and can last for 12–18 months | Clinical evaluation |
Sometimes upper respiratory infection prodrome Typically begins as a single, pruritic 2- to 10-cm oval red herald patch on the trunk or proximal limbs 7–14 days after the herald patch, appearance of large patches of pink or red, flaky, oval-shaped rash on the torso, sometimes in a characteristic Christmas tree–like distribution | Clinical evaluation | |
* This cause is currently uncommon because of vaccination but should be considered in unvaccinated children. | ||