Peds rashes

• contact dermatitis

• cellulitis

• atopic dermatitis

• urticaria

Answer explanation

Red, edematous, papules/ plaques that can coalesce, very pruritic

Characteristic: individual lesions are transient (<24 hrs)- rash migrates

Mast cell IgE degranulation

Many possible causes, sometimes idiopathic

Tx: both H1 and H2 blockers

• frostbite

• furuncle

• fixed drug eruption

• psoriasis

Answer explanation

Sharply demarcated oval. Red to dusky color. Often on face, hands, feet, genitals. Can become bullous. If symptomatic, would be itchy or burning.

Hyperpigmentation lasts for months

Starts w/in 2 weeks of starting the med

Tx: if super itchy, can treat with topical steroids

• neonatal lupus

• tinea corporis

• erythema multiforme

• nummular eczema

Answer explanation

Red annular rash, usually on head and neck. High suspicion if periorbital

Passive maternal transfer of antibodies anti-Ro, anti-La, U1-RNP

Other health consequences: cytopenias,arrhythmias

Red ring rash in a newborn- neonatal lupus until proven otherwise

• VZV-chicken pox

• erysipelas

• measles

• rocky mountain spotted fever

Answer explanation

Measles/rubella have the same rash: Pink to red macules/papules. Starts on the head and spreads down and out. In measles they often become confluent and in rubella they generally don’t

Koplik spots in measles but not rubella

Cough, conjunctivitis, runny/stuffy nose, and malaise common to both

• SJS

• hand, foot, mouth

• impetigo

• atopic dermatitis

Answer explanation

Papules→pustules→break open to form typical “honey-crusted” lesion

Stay localized, typically involves the face or sometimes extremities

Patients usually 2-5 years old

Mostly strep, can be staph

Tx= topical abx (mupirocin)

• tinea corporis

• erythema migrans

• contact dermatitis

• atopic dermatitis

Answer explanation

Scaling patch with an annular raised border

Dermatophyte infection

Transmitted person to person mostly by fomites (towels, bedding, wrestling mats). Warm, humid environments

Tx= topical azoles (clotrimazole, ketoconazole)

• VZV- shingles

• scabies

• contact dermatitis

• folliculitis

Answer explanation

Papules and pustules centered around hair follicles

Bacterial invasion of the hair follicle. Usually Staph, sometimes GAS. Pseudomonas in case of recirculating water- “hot tub folliculitis”

Tx= topical abx for staph. Hygiene/source avoidance for pseudomonas

• henoch-schonlein purpura

• ecthyma

• bullous impetigo

• fixed drug eruption

Answer explanation

Ulcerative form of impetigo

Lesions extend through the epidermis into the dermis

“punched out” ulcers with golden crust and violaceous margins

• erythema marginatum

• erythema migrans

• erythema infectiosum

• erythema multiforme

Answer explanation

Evanescent rash, pink or red. Usually annular with sharp outer borders and less clear inner borders.

Also described as serpiginous.

individual rings come and go, sometimes within hours.

One of the major JONES criteria for acute rheumatic fever, rarely seen alone

Aka erythema annulare

• HSV

• VZV- shingles

• VZV- chicken pox

• measles (obviously this is not the right answer)

Answer explanation

Painful, unilateral, erythematous, vesicular

Caused by reactivation of VZV

Classically thought of as a disease of older or immunocompromised

Patients can transmit VZV, causing chickenpox in varicella-naïve children