[Cholesterol crystal emboli presenting as a mononeuropathy].

Cholesterol crystal embolism is observed in polyvascular patients usually following a medical procedure. We report a 93-year-old patient with lower limb mononeuropathy in whom cholesterol crystal embolism was confirmed by neuromuscular biopsy. Previously, an ophthalmoscopy and a livedo biopsy had been performed and the results were normal. Mononeuropathy simplex or multiplex is a clinical expression for cholesterol crystal embolism that may thus be confounded with polyarteritis nodosa. Neuromuscular biopsy can provide accurate diagnosis if other investigations are inconclusive.