Calciphylaxis in a dialysis patient diagnosed by muscle biopsy.

Calciphylaxis is a rare condition seen mostly in patients with chronic renal disease and secondary hyperparathyroidism who develop painful skin lesions and myopathy secondary to extensive small vessel calcification, which leads to tissue ischemia. It is typically diagnosed by a biopsy of prominent skin lesions. Here, we report a 49-year-old man with end-stage renal disease on chronic peritoneal dialysis who presented with weakness, myalgias, and necrotic skin lesions. Multiple skin biopsies were nondiagnostic because of severe extensive necrosis, and the diagnosis of systemic calciphylaxis was eventually made by a muscle biopsy. This case demonstrates the significant muscle involvement in calciphylaxis and highlights the importance of maintaining a high clinical suspicion for patients with risk factors for calciphylaxis, even when skin biopsy does not confirm it.