[Rhabdomyolysis in patients with preexisting myopathy, treated with antilipemic agents]

Lipid lowering drugs (fibrates and statins) are generally well tolerated and side effects, mainly hepatic and muscular disorders are rare. However, when they occur, muscular disorders may be severe, leading to rhabdomyolysis. We report here four cases of rhabdomyolysis in patients given lipid lowering drugs and who had pre-existing myopathy.

The four patients complained of muscle pain after treatment with niacin, HMGCoA inhibitors, as well as fibrates. The myopathy was not recognized at the time of prescription in three cases. Myopathy resolved rapidly upon discontinuation of the drugs and none of the patients developed renal failure.

This is the first report of rhabdyomyosis induced by lipid lowering drugs in patients with pre-existing myopathy. Drug induced myopathy is a known complication of lipid lowering drugs either alone or in patients with other conditions such as renal failure, immunosuppressive therapy for cardiac transplantation, or in case of combination regimens. Such a side effect without concomitant disease has not been reported previously in patients with congenital myopathy. Cholestyramine is the drug of choice for these patients. Our observations suggest that the rhabdomyolysis provoked by lipid lowering drugs may be favored by pre-existing myopathy.