Condition	Location	Appearance	Fever	Pruritus	Distinguishing features	Duration
Roseola infantum (exanthema subitum)	Trunk, spreads peripherally	Macular to maculopapular	High fever, usually greater than 102°F (39°C), precedes the rash; child is otherwise well-appearing	No	Can be confused with measles; measles rash begins on the face, and the child is usually ill-appearing	1 to 2 days
Pityriasis rosea	Trunk, bilateral and symmetric, Christmas tree distribution	Herald patch on the trunk may present first, followed by smaller similar lesions; oval-shaped, rose-colored patches with slight scale	No	Occurs in up to one-half of patients	Often confused with tinea corporis; pityriasis rosea is typically widespread, whereas tinea corporis usually causes a single lesion	2 to 12 weeks
Scarlet fever	Upper trunk, spreads throughout body, spares palms and soles	Erythematous, blanching, fine macules, resembling a sunburn; sandpaper-like papules	Occurs 1 to 2 days before rash develops	Usually no	Petechiae on palate; white strawberry tongue; test positive for streptococcal infection	Several weeks
Impetigo	Anywhere; face and extremities are most common	Vesicles or pustules that form a thick, yellow crust	Usually no	No	May be a primary or secondary infection; bullous form is typical in neonates, and nonbullous form is more common in preschool- and school-aged children	Usually self-limited but often treated to prevent complications and spread of the infection
Erythema infectiosum (fifth disease)	Face and thighs	Erythematous “slapped cheek” rash followed by pink papules and macules in a lacy, reticular pattern	Low grade	Yes	May be confused with scarlet fever; the slapped cheek rash can differentiate erythema infectiosum	Facial rash lasts 2 to 4 days; lacy, reticular rash may last 1 to 6 weeks
Molluscum contagiosum	Anywhere; rarely on oral mucosa	Flesh-colored or pearly white, small papules with central umbilication	No	Yes, if associated with dermatitis	Usually resolves spontaneously without treatment	Months or up to 2 to 4 years
Tinea infection	Anywhere	Alopecia or broken hair follicles on the scalp (tinea capitis), erythematous annular patch or plaque with a raised border and central clearing on the body (tinea corporis)	No	Yes	Often confused with pityriasis rosea; potassium hydroxide microscopy can help confirm diagnosis	Usually requires antifungal treatment
Atopic dermatitis	Extensor surfaces of extremities, cheeks, and scalp in infants and younger children; flexor surfaces in older children	Erythematous plaques, excoriation, severely dry skin, scaling, vesicular lesions	No	Yes	Emollients and avoidance of triggers are the mainstay of treatment; topical corticosteroids may be needed for flare-ups	Chronic, relapsing