Confluent muscle pallor: a macroscopic marker of cocaine-induced rhabdomyolysis

A 39-year-old man presenting with acute delirium is reported who suffered an unexpected cardiac arrest shortly after being sedated. Death followed 2 days later from hypoxic-ischemic encephalopathy. At autopsy, marked pallor and edema of his left sternomastoid muscle was observed which was shown on microscopy to be due to confluent coagulative necrosis. Myoglobin casts in his renal tubules corresponded to an antemortem creatine phosphokinase level of 31,940 U/l. Death was due to rhabdomyolyisis and excited delirium complicating cocaine toxicity with hypoxic-ischemic encephalopathy, against a background of atherosclerotic coronary artery disease. Extensive confluent pallor in a single muscle may be a useful marker of chronic cocaine exposure associated with hyperthermia and muscle necrosis. Confirmatory toxicology is required.