Painful ulcers

Abstract

A 65-year-old woman presented with a 6-week history of painful ulceration on her thighs and buttocks. Comorbidities included primary hyperparathyroidism, multiple sclerosis, diabetes, chronic kidney disease (stage 3), obesity and atrial fibrillation. She was taking warfarin but not calcium-channel blockers. Physical examination revealed multiple large ulcers with necrotic eschar on skin that was firm to palpation, in keeping with subcutaneous calcification. There were purpuric patches over the buttocks and thighs (Fig. 1a,b). Laboratory investigations gave the following results: corrected calcium 3.4 mmol/L (normal range 2.2-2.6 mmol/L), phosphate 1.51 mmol/L (0.8-1.50 mmol/L), parathyroid hormone 16.5 pmol/L (1.6-7.5 pmol/L) and estimated glomerular filtration rate 48 mL/min (> 60 mL/min). C P Dª