Korsakoff psychosis -

Ans. is 'a' i.e., Thiamine deficiency o Wernicke - Korsakoff syndrome or wemicke-Korsakoff psychosis is the name given for the amnestic disorders which include Wernicke's encephalopathy (a set of acute symptom) and Korsakoff syndrome (a chronic condition).o These two syndrome occur due to deficiency of thiamine.o Most common cause precipitating thiamine deficiency (causing wernicke-Korsakoff syndrome) is chronic alcoholism.o Other precipitating causes are prolonged starvation causing malnutrition (marasmus), hyperemesis gravidarum, HIV-AIDS, bariatric surgery, prolonged intravenous hyperalimentation, hemodialysis for CRF, and malignancies (gastric carcinoma).o Thiamine is a cofactor for several important enzymes (transketolase, pyruvate dehydrogenase & a-ketoglutarate dehydrogenase).o Thiamine deficiency results in decreased utilization of glucose and accumulation of glutamate which causes excitatory damage to neurons.o Acute damage (in wernicke's encephalopathy) causes petechial hemorrhage in thalamus, mammillary bodies, midline cerebellum, periaqueductal gray matter of midbrain, and peripheral nerves.o In chronic disease (Korsakoff's syndrome) there is atrophy of mammillary body, medial thalamic nuclei, and hippocampus.