Neurological Complications of Heroin

1. Neurological Complications of Heroin Department of Neurology Alfred Hospital 26 April, 2000.

2. HEROIN • Diacetyl derivative of morphine • Usual route of administration is intravenous. Other routes include intramuscular, subcutaneous, rectal & intranasal • After absorption, rapidly converted into morphine or monoacetylmorphine which is highly lipid soluble allowing good BBB penetration to cause morphine euphoria or “high”

3. EPIDEMIOLOGY • Onset of use usually in late adolescence peaking at age 18-20 • 2/3 addicts start using the drug before 21 years of age • changing spectrum • route: intranasal “chasing the dragon” becoming • more popular • contaminants: increasing purity of supplies • safety profile: clean needles • culture: no longer confined to lower socioeconomic • classes

4. DIFFICULTIES OF ANALYSISIS IT TRULY A COMPLICATION OF HEROIN? • Contaminants: Chinese heroin has caffeine • Iran heroin has strychnine • Lactose, mannitol, quinine • Talcum powder, starch, Ajax, curry powder • Abuse of other drugs concomitantly • Pathophysiology as direct toxicity / drug induced vasculitis / hypersensitivity

5. SOURCE OF INFORMATIONLANDMARK STUDY • In 1972, necropsy studies of • 899 acute narcotic deaths • 541 narcotic related deaths - 327 homicide • 48 infections •          166 other causes • Department of Forensic Medicine of New York University • J. Pearson & R. Richter, 1975 in Medical Aspects of Drug Abuse

6. NEUROLOGICAL COMPLICATIONS OF ADDICTION TO HEROIN Part I • Addiction • Cerebral complications of narcotic overdose • Coma without complications • Coma with neurological sequelae • Seizures • Increased intracranial pressure • Acute delirium • Delayed postanoxic encephalopathy • Stroke • Involuntary movement disorder • Deaf ness • Toxic (quinine) amblyopia • Transverse myelitis

7. NEUROLOGICAL COMPLICATIONS OF ADDICTION TO HEROIN Part II • Peripheral nerve lesions • Brachial & lumbosacral plexitis • Atraumatic & traumatic mononeuropathy • Polyneuropathy • Muscle disorders • Acute rhabdomyolysis • Chronic myopathy • Crush syndrome & other forms of localized muscle damage • Infectious & Postinfectious neurological Complications • Cerebral complications of endocarditis & other septic states • Local abscesses with muscle or nerve involvement • Cerebral complications of hepatitis • Tetanus • HIV

8. HEROIN ADDICTION • Medical, social & psychiatric disease • Features: • Episodic intoxication or “euphoria” • Pharmacological dependence (tolerance, physical dependence) • Drug seeking behavior • Propensity to relapse after abstinence • The most common neurological complication of heroin in the community.

9. CEREBRAL COMPLICATION OF HEROIN OVERDOSE • COMA WITHOUT COMPLICATIONS • Hypercapnia, hypoxia, cardiorespiratory arrest • 5% have seizures which stop permanently at time of recovery from overdose • Most recover & discharged

10. CEREBRAL COMPLICATION OF HEROIN OVERDOSE • COMA WITH NEUROLOGICAL SEQUELAE • Neuropathologically • Brain edema, myelin damage, astrocytic clasmatodendrosis, globus pallidus cysts & reduced neuronal populations. • Watershed infarction • Delayed anoxic encephalopathy: residual weakness, cognitive impairment, spasticity. • Movement disorders: Parkinsonism, dystonias

11. TRANSVERSE MYELITISCASE ILLUSTRATION • Rare • Within 24 hours of intravenous use • Pathology: extensive necrosis of cervical & thoracic cord involving grey & sparing white matter. • Pathophysiology • Watershed infarction • Hypersensitivity reaction to heroin or its contaminants • Direct toxic effect of heroin & its contaminants • Hyperextension injury • Differential Diagnosis: • Embolism, demyelination, hyperextension injury, infection (HSV, Mycoplasma, VZV)

12. PERIPHERAL NERVE LESIONS • Traumatic or pressure neuropathy: sciatic from lotus position • radial nerve palsies • other pressure palsies • accidental injection into a nerve • Atraumatic neuropathy: painless weakness beginning 2-3 hrs • after iv injection usually remote from • the symptomatic extremity • EMG/NCS: general slowing rather than focal slowing • Plexitis: similar to above • Lumbosacral plexitis are usually • painful

13. MUSCLE DISORDERS • Acute rhabdomyolysis: Vigorous rhabdomyolysis with minimal trauma • Generalized muscle tenderness • Moderate to severe weakness • Chronic myopathy: chemical toxic effect of direct intramuscular • injection & infection eg long term “skin • poppers” • Crush syndrome: due to pressure or injection into enclosed • fascial compartment eg forearm

14. OTHER NEUROLOGIC COMPLICATIONS OFHEROIN ADDICTION • Heroin related spongiform encephalopathy from “chasing the dragon” • Toxic (quinine) amblyopia • Endocarditis • Epidural abscesses • HIV neurology • Etc

15. SUMMARY • •Commonest neurological complication in the community is addiction • • Commonest neurological complication in the hospital is coma due to overdose • • An unusual neurological contribution should not be immediately attributed to heroin. • • Diagnosis of heroin related neurological complication should bear in mind temporal relationship to the use, other drugs or diseases that could mimic the condition should be excluded. • • Spectrum of disease may change with the change in drug culture, routes of administration & changing purity of the drug. • • Treating a patient with an interesting heroin related neurological complication is insufficient unless social & rehabilitative as well as medical issues are addressed with a view to returning the patient to a more complete life.