Ischemic myopathy revealing systemic calciphylaxis.

Patients with renal failure who are being treated with dialysis frequently develop neuromuscular manifestations. Renal failure-associated calciphylaxis, also termed calcific uremic arteriolopathy (CUA), is a life-threatening condition usually observed in patients with end-stage renal disease on chronic dialysis or after renal transplantation.

We describe a hemodialyzed patient who presented with rapidly progressive unexplained systemic vasculopathy, muscle atrophy, and proximal weakness, that unexpectedly proved to be caused by calciphylaxis.

Quadriceps muscle biopsy disclosed diffuse vascular calcific deposits on medium- and small-sized vessels, characteristic of CUA. Other changes included ischemic myopathy, focal intracellular calcium accumulation within myofibers, and calcium deposits in endomysial capillaries associated with marked complement activation and C5b9 formation.

There are only a few descriptions of muscle involvement in the context of CUA, a condition with a prognosis that depends on early diagnosis and treatment. This report underscores the usefulness of muscle biopsy in the diagnosis of systemic calciphylaxis. Muscle Nerve 56: 529-533, 2017.