1. ALCOHOL AND THE NERVOUS SYSTEM DR M KAKAZA

2. COMMON COMPLICATIONS Nutritional deficiency Diseases partly nutritional in origin Direct effects of alcohol Abnormalities of electrolytes and osmolality Diseases of uncertain pathogenesis

3. A. Nutritional Complications Wernicke’s Encephalopathy Korsakoff’s syndrome Pellagra

4. 1. Wernicke’s Encephalopathy Clinical features include: Confusion Opthalmoplegia Ataxia MRI features: ( T2, Diffusion-weighted and FLAIR) Signal changes in periaqueductal gray matter, medial thalami and mamillary bodies

5. Wernicke’s Encephalopathy…. Treatment: – Thiamine 100mg ivi stat then daily throughout the acute stage NB alcoholics may have poor intestinal absorption

6. Wernicke’s Encephalopathy…. Other causes: – Hyperemesis of pregnancy – Systemic malignancy – GIT surgery – Prolonged iv feeding – Re-feeding after prolonged fast – Anorexia nervosa – Dieting and gastric plication – AIDS

7. 2. Korsakoff’s Syndrome Russian Psychiatrist Wernicke and Korsakoff’s syndrome are different stages of the same disease process. Korsakoff’s follows Wernicke’s and tends to appear as ocular symptoms and encephalopathy improve

8. Korsakoff’s syndrome…. Memory is impaired out of proportion to other cognitive functions – Amnestic syndrome Have inability to form new memory

9. Korsakoff’s Syndrome…. Clinical features: Memory loss Confabulation Alertness, attention, social behavior intact Localization of the lesion Diencephalon Temporal lobes

10. 3. Pellagra Due to Nicotinic acid deficiency From Italian ‘pelle agra’ which means ‘dry skin’ Nicotinic acid is converted to NAD and NADP NAD and NADP are coenzymes required in the metabolism of carbohydrates

11. Pellagra….. Clinical triad: – Dementia – Dermatitis – Diarrhea

12. Pellagra…. Communities that depend on corn for their diet can suffer from pellagra. Corn lacks tryptophan, a precursor that can be converted to nicotinic acid in the body.

13. Pellagra…. Bread is now enriched with niacin Treatment: – Nicotinic acid ivi 25mg bd or tds

14. B. Direct Effects of Alcohol Acute intoxication Fetal alcohol syndrome Alcohol withdrawal seizures Delirium tremens

15. Stages of acute alcohol intoxication BLOOD LEVEL 0.01 – 0.05 0.03-0.12 0.09-0.25 0.18-0.30 0.25-0.40 0.35-0.50 0.45+ STAGE Subclinical Euphoria Excitement Confusion Stupor Coma Death

17. C. Abnormalities of Serum Electrolytes and osmolality Hyponatremia Hypocalcemia Hypomagnesemia Hypophosphatemia

18. Central pontine myelinolysis

20. D. Diseases at least partly nutritional in origin Alcoholic neuropathy Amblyopia

21. 1 Alcoholic Neuropathy Most common complication Distal symmetrical polyneuropathy Mixed sensory motor disorder Pathology – Axonal loss Pathogenesis: – Direct alcohol neurotoxicity – Thiamine deficiency

22. 2. Amblyopia Vision loss caused by a selective lesion of the optic nerves History – chronic alcoholic, poor dietary intake, loss of weight Most likely due to nutritional deficiency Treatment – Good nutrition, B vitamins Prognosis – Improves on treatment (despite continued drinking)

23. E. Diseases of uncertain pathogenesis Alcoholic myopathy Alcoholic dementia Cerebellar degeneration Marchiafava-Bignami Syndrome

24. 1. Cerebellar Degeneration Associated with long-standing use of alcohol Patients often have neuropathy as well Presentation – Progressive unsteadiness of gait – Trunkal ataxia

25. Cerebellar Degeneration…. Pathological changes: Selective atrophy of the anterior and superior parts of the vermis Histological changes: Purkinje’s cells most severely affected

26. 4. Marchiafava-Bignami Syndrome Italian pathologists Described in 1903 Clinical picture difficult Mental slowing, Motor slowing, Personality or behaviour changes, Incontinence, Seizures, Dysarthria and hemiparesis

27. Marchiafava-Bignami Syndrome…. Patholological changes: – Selective demyelination of the corpus callosum