ABD Pediatric Dermatology cheat sheet

Atopic dermatitis: pruritus plus xerosis with flexural involvement in children; onset often before age 5; treat with emollients plus topical corticosteroids by severity.

Infantile hemangioma: appears within first weeks of life, proliferates for 3-6 months, then involutes over years; high-risk sites (periorbital, airway, lumbosacral, beard area) warrant early intervention.

Miliaria crystallina: superficial 1-2 mm clear vesicles from eccrine duct obstruction; miliaria rubra is erythematous papules; both resolve with cooling and reduced occlusion.

Erythema toxicum neonatorum: blotchy erythema with yellow-white papules/pustules on trunk and face in first days of life; eosinophils on smear; self-limited.

Transient neonatal pustular melanosis: pustules present at birth that rupture leaving collarette scale and hyperpigmented macules; neutrophils on smear; no treatment needed.

Kawasaki disease: fever 5 or more days plus conjunctivitis, mucosal changes, extremity changes, rash, cervical adenopathy; risk of coronary aneurysms; treat with IVIG plus aspirin.

Tinea capitis in children: scaly patches with broken hairs or black-dot alopecia; dermatophyte culture or KOH confirms; treat with oral griseofulvin or terbinafine, not topical alone.

Measles rash: maculopapular eruption beginning at the hairline and spreading downward, with Koplik spots and a 3-4 day prodrome of fever, cough, coryza, and conjunctivitis.

Scabies in infants: burrows on palms and soles, vesiculopustules, and nodules; treat with permethrin 5% or oral ivermectin by weight, and treat close contacts.

ABCDE melanoma criteria: Asymmetry, Border irregularity, Color variation, Diameter greater than 6 mm, and Evolution or change over time.

Psoriasis: well-demarcated erythematous plaques with silvery scale on extensor surfaces; Auspitz sign is pinpoint bleeding after scale removal; treat with topical corticosteroids, vitamin D analogs, or phototherapy.

Lichen planus: pruritic purple polygonal planar papules with Wickham striae; classic 6 Ps; may involve oral mucosa and nails.

Stevens-Johnson syndrome and toxic epidermal necrolysis: epidermal detachment under 10% and over 30% body surface area respectively; mucosal involvement and Nikolsky sign positive; drug-induced in most cases.

Pemphigus vulgaris: intraepidermal acantholysis with flaccid bullae and oral erosions; direct immunofluorescence shows intercellular IgG; treat with systemic corticosteroids and steroid-sparing agents.

Bullous pemphigoid: subepidermal blister with linear IgG and C3 at the basement membrane zone; tense bullae in older adults; treat with topical or systemic corticosteroids.

Cellulitis: acute spreading erythema, warmth, and tenderness without fluctuation; Streptococcus and Staphylococcus are common; mark borders and treat with appropriate antibiotics.

Tinea versicolor: hypopigmented or hyperpigmented scaly macules on the trunk from Malassezia; KOH shows spaghetti-and-meatballs; treat with topical selenium sulfide, ketoconazole, or oral azoles.