Itching to learn: school chair allergic contact dermatitis on the posterior thighs.

A 10-year-old girl with a history suggestive of nickel allergy presented with pruritic, eczematous plaques on her posterior thighs. Patch testing revealed sensitivities to nickel, cobalt, and chromium. The pattern of her involvement suggested an "outside job," and subsequent investigations confirmed that the exposed metal fasteners on her school chair were the likely source of her focal contact dermatitis. Medical history-taking, clinical observation, and investigative follow-through are essential when trying to identify a specific source of contact dermatitis in the pediatric and adolescent populations.