[Idiopathic paroxysmal rhabdomyolysis and clinically latent myopathy]

Rhabdomyolysis can appear secondarily in the course of many different diseases, but also primarily as "idiopathic paroxysmal rhabdomyolysis" (i.p.r.), simulating clinically an acute myositis. Different factors can trigger this muscle reaction, the most important of them being physical stress, alcoholism, drug dependence, general anesthetics. In many of these cases biopsy investigations do disclose, out of rhabdomyolysis, a preexistent myopathy, usually dysmetabolic in origin, and often with familial incidence (lipid myopathies; carnitine palmityl-transferase deficiency; mitochondrial myopathies; glycogenoses; hypokaliaemia--but also central core diseases, tubular aggregates myopathy a.s.o.). Exact morphological and biochemical investigations are therefore needed in every case of i.p.r., with the purpose to identify the underlying myopathy in the patients and their relatives. Repeated controls of CPK values should be performed. Bearers of such subclinical myopathies have in fact to be considered patient at-risk if exposed to stress or if submitted to general anesthesia.