Case Report: Morphologically striking eruptive xanthomas with lobulated papules: a sentinel sign of severe metabolic dysregulation

Eruptive xanthoma (EX) is a rare but clinically important dermatologic manifestation of severe hypertriglyceridemia and often serves as a cutaneous indicator of profound disturbances in glucose metabolism. Here, we describe a 27-year-old man who presented with numerous yellowish papules that clustered into lobulated, cauliflower-like plaques on the trunk and limbs, serving as the first clinical indication of underlying metabolic dysregulation. Laboratory investigations revealed extreme hypertriglyceridemia (60.45 mmol/L) and newly diagnosed diabetes mellitus (HbA1c 14.1%). Skin biopsy demonstrated foamy histiocytes and Touton giant cells in the dermis. The patient received combination therapy with fenofibrate (200 mg/day), intensive insulin therapy, and a low-fat diabetic diet, leading to rapid normalization of triglyceride levels from 60.45 mmol/L to 2.47 mmol/L by Day 32. The cutaneous lesions flattened and progressively regressed in parallel with metabolic improvement, leaving only faint post-inflammatory hyperpigmentation at the final evaluation. This case emphasizes that uncommon lobulated morphology may serve as an early visual clue of eruptive xanthomas, reinforcing the diagnostic value of cutaneous signs as metabolic sentinels and highlighting that early dual-target treatment can prevent life-threatening complications.