
Can you guess the diagnosis?

Can you guess the diagnosis?

Can you guess the diagnosis?

The parents of a healthy 20-month-old boy ask for advice about a birthmark on his lower back. The lesion is asymptomatic and has grown proportionately with their son. What's the diagnosis?

An otherwise healthy 5-month-old girl presents with an asymptomatic, rapidly growing, firm, smooth nodule on the side of her left fifth finger since she was 2 months of age.

A healthy 3-year-old girl presents for evaluation of light brown spots on her trunk and extremities that have appeared over the last 2 years. The spots are not symptomatic but the girl’s parents are worried that she could have neurofibromatosis.

A 16-year-old girl presents to the clinic for acne follow-up and mentions that her palms wrinkle significantly after only a few minutes of immersion in water. She is otherwise well and has no significant past medical history.

An 8-year-old boy is brought to the office for evaluation of a persistent itchy rash on his extremities, trunk, and face. Although the rash has been present for longer than 3 months, individual skin lesions change from hour to hour and occasionally the rash clears completely only to recur several hours later. He is otherwise healthy with no known allergies, changes in diet, medication use, or recent illness.

An anxious mother brings her healthy 4-month-old daughter for evaluation of itchy pustules on both hands and feet. The eruption has persisted despite 2 courses of permethrin for scabies. The infant also was diagnosed with hand-foot-and-mouth syndrome and dyshidrotic eczema, but neither of these diseases fit clinically.

A 16-year-old boy develops a diffuse, rapidly progressive eruption on his trunk, face, and extremities 4 days after starting oral amoxicillin for presumed strep throat. He presents to the emergency department (ED) where Stevens-Johnson syndrome is considered. The ED physician notes no mucous membrane involvement.

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