Pediatric Dermatology Subspecialty
Neonatal and infant skin
Pediatric questions emphasize age-specific presentations. Know transient neonatal eruptions: erythema toxicum neonatorum (eosinophils, sterile pustules), milia, miliaria, and neonatal acne. Distinguish these from serious entities like staphylococcal scalded skin syndrome and herpes simplex neonatorum, which require urgent action.
Common pediatric disorders
Atopic dermatitis follows an age-related distribution (face and extensor in infants, flexural later). Diaper dermatitis has irritant, candidal, and seborrheic forms. Know tinea capitis (dermatophyte, often Trichophyton tonsurans, requires oral therapy), molluscum contagiosum, and hand-foot-and-mouth disease. Vascular anomalies: infantile hemangioma (GLUT1 positive, proliferates then involutes) versus vascular malformations (present at birth, do not involute).
Genetic and systemic clues
Recognize neurofibromatosis (café-au-lait, axillary freckling), tuberous sclerosis (ash-leaf spots, angiofibromas), and incontinentia pigmenti (Blaschko-linear stages).
Traps
Questions often test treatment differences from adults-e.g., low-potency steroids in infants, avoidance of tetracyclines, and oral griseofulvin or terbinafine for tinea capitis. Another trap is mislabeling a vascular malformation as a hemangioma.
Rule of thumb
If a vascular lesion is fully present at birth and grows proportionally with the child, it is a malformation; if it appears after birth, proliferates rapidly, then fades, it is an infantile hemangioma.
Worked example
A 6-month-old with a rapidly enlarging bright red facial plaque: infantile hemangioma. If the lesion is a large, soft, violaceous mass present at birth, consider a venous or lymphatic malformation instead.