Dermatology AdvisorRed Bumps on the Fingers

🧩 Diagnostic Reasoning Exercise / Teaching Case
A previously healthy adolescent develops red, itchy, and sometimes painful bumps on his fingers in early December. Initial lesions resolved, but new lesions appeared after a weekend ski trip. Examination reveals erythematous, tender papules on the lateral and dorsal aspects of the distal fingers. No medications, no significant past medical history.

Diagnostic Considerations

• The cold and wet exposure history with seasonal onset narrows the differential toward vasoreactive and cold-induced inflammatory conditions.
• Lesion distribution on dorsal and lateral distal phalanges rather than digital tips helps distinguish among the listed entities.
• Lesion morphology (papules and nodules with edema and tenderness) versus episodic color change without papules carries diagnostic weight.
• Persistent or atypical cases warrant workup for secondary causes, including cryoglobulinemia, antiphospholipid syndrome, SLE, and hematologic conditions.

Practice Pearls

• Consider seasonality and humidity exposure when evaluating acral inflammatory lesions in adolescents.
• Recognize that low BMI and impaired thermoregulation predispose certain patients to cold-induced acral conditions.
• Integrate prevention counseling (warm dry acral coverage, nicotine avoidance) before escalating to pharmacologic management.
• Monitor for chronic or recurrent presentations that may signal an underlying systemic process requiring further workup.