The neuropathology of cocaine abuse.

Cocaine abuse represents a worldwide significant forensic issue as it is becoming widely recognized as one of the most dangerous illicit drugs in common use today. Besides cardiovascular complications, psychiatric and neurologic symptoms are the most common manifestations of cocaine toxicity. The latter include seizures, movement disorders and cerebrovascular complications. In chronic cocaine abusers morphological, physiological, and neurochemical abnormalities have been demonstrated by using neuroradiological techniques such as computed tomography, magnetic resonance imaging, positron emission tomography or single photon emission computed tomography. The spectrum of neuropathologic changes encountered in the brains of cocaine abusers is broad, but the major findings consist of ischemic and hemorrhagic stroke, subarachnoid and intracerebral hemorrhages and cerebral ischemia. Especially persons with underlying arteriovenous malformation or aneurysm are at risk for such events. Except for a few instances of vasculitis, the etiology of cocaine-related cerebrovascular accidents is still unclear. Besides pharmacologically-induced vasospasm, impaired hemostasis and platelet function and decreased cerebral blood flow have been proposed. At the cellular level, abnormalities in the expression of transcription factors and changes of brain neurotransmitter systems have been reported.