Acute heroin-related neuropathy

Area of Science:

• Neurology
• Toxicology
• Neuroscience

Background:

• Peripheral nervous system (PNS) injuries from heroin use are rare, often presenting as compressive neuropathies.
• Other PNS injuries, including plexopathy and neuropathy, have been anecdotally reported but their etiology remains unclear.
• Proposed immunologic mechanisms lack consistent laboratory evidence and do not typically respond to steroid treatment.

Observation:

• Six patients developed acute PNS injuries after intravenous or intranasal heroin use without evidence of compression or inflammation.
• Four patients presented with plexopathy (lumbosacral or brachial), and two with symmetric distal sensorimotor neuropathy.
• Five patients had concurrent rhabdomyolysis, indicated by elevated creatine kinase (CK) levels.

Findings:

• Neurological deficits manifested 3-36 hours post-heroin administration.
• Electromyography confirmed sensorimotor axonal loss, localized to plexuses or diffuse in the lower extremities.
• No signs of local trauma, inflammation, or compression were identified in the affected nerves.

Implications:

• The findings suggest a direct toxic effect of heroin or its adulterants on the peripheral nervous system.
• This toxic mechanism offers an alternative explanation for acute, non-compressive neuropathies in heroin abusers.
• Further research into the neurotoxic properties of heroin is warranted to understand and prevent these debilitating injuries.