History: A 30 yr old obese man presents with an asymptomatic rash on his back, arms, and hands that had developed 2 week earlier. On physical examination, scattered pink-yellow papules were present on the upper back, extensor surfaces of the upper arms, and dorsa of the hands. A fasting blood sample was grossly lipemic. Which of the following is the most likely diagnosis?
- Eruptive xanthomas
- Sebaceous hyperplasia
- Granuloma annulare
- Molluscum contagiosum
Answer: Eruptive xanthomas typically present as crops of 2–5 mm yellow papules with a red rim over extensor surfaces such as the buttocks or shoulders, but can be widespread including inside the mouth. The papules may be tender and are usually itchy. They may demonstrate köbnerisation. Eruptive xanthomas are due to hypertriglyceridaemia (triglyceride >11.2 mmol/L) of any cause.