Alcoholism

Question 1

General information

Answer 1

In sporadic drinkers, 50mg/dl alcohol will be enough to give a visible intoxication. In alcoholics the same signs show after 125-150mg/dl. People with chronic alcoholism can tolerate increased levels partly due to accelerated ethanol metabolism caused by increased activity of the hepatic cytochrome P450 system.

Question 2

Biochemistry of alcohol metabolism

Answer 2

Alcohol dehydrogenase, located in the cytosol of the hepatocytes
Cytochrome P450 - particularly the CYP2E1 isoform located in the smooth ER which is capable of being induced but is low sensitivity.
Catalase - which only has a minor importance.

These enzymes produce acetaldehyde from ethanol, which can again be converted to acetate.

Question 3

Treatment of severe tremulousness (shivering) or delirium tremens (abstinential shivering/response)

Answer 3

1. Attempt to get control by reassurance and observations
2. Diazepam for patients having trouble calming down. Give 10mg IV slowly, keep giving 5-10 mg IV slowly every 5 minutes to induce calmness. Once the patient is calm, maintain with diazepam 5-10mg IV every 1-4 hours
3. Continuously supply the patient with vitamins and electrolytes, especially thiamine
4. Treat systemic problems as they occur

Question 4

Major non-neurological complications of alcoholism

Answer 4

1. Heart: cardiomyopathy, arhythmia
2. GI: gastritis, hepatitis, fatty liver (due to alcohol dehydrogenase using NAD+ normally required for fatty acid oxidation), Cirrhosis, pancreatitis, head-and-neck cancer, malabsorption
3. Blood: iron and folate deficiencies, often increased biliary obstruction enzymes such as ALP and GGT
4. Endocrine: male sexual impairment, increased fetal risk
5. Immune system: increased susceptibility to infections and impaired healing
6. Electrolyte disturbances: hypocalcemia, hypomagnesemia, hypophosphatemia, acute water intoxication, alcoholic hyperosmolarity, alcoholic ketosis

Question 5

Major neurological complications

Answer 5

1. Amblyopia and optic atrophy
2. Progressive cerebral degeneration and dementia
3. Peripheral neuropathy (more often due to thiamine deficiency
4. Myopathy
5. Wernicke-Korsakoff disease (often due to thiamine deficiency)
6. Parenchymatous cerebellar degeneration
7. Cerebral leukodystrophy (Marchiafava-Bignami)

Question 6

Wernicke-Korsakoff disease

Answer 6

• Confusion, abnormalities in eye movements, and ataxia is a syndrome termed Wernicke encephalopathy. Characteristic is hemorrhage and necrosis, particularly in the maxillary bodies, but also adjacent to the ventricles.
• Iverreversible profound memory disturbances is termed Korsakoff syndrome.
• These two syndromes are often closely linked