A 50-year-old chronic alcoholic presented with complaints of acute confusion, delirium, ataxia and mild memory loss. On ophthalmoscopic examination, ophthalmoplegia was noted along with hypotension. Serum electrolyte levels were normal. Lab findings revealed increased RBC transketolase activity along with reduced blood lactate levels. CT scan of the brain did not reveal any finding, so MRI of brain was planned. Which of the following enzymes uses the above deficient vitamin as a coenzyme: -
This is a case of Wernicke's encephalopathy. It occurs due to deficiency of vitamin B1. The clinical diagnosis of WE in alcoholics requires two of the following four signs: dietary deficiencies eye signs cerebellar dysfunction either an altered mental state or mild memory impairment. This MRI shows typical high signal intensities (SIs) in the medial thalamus (A), periaqueductal gray (B), mamillary bodies (C), cerebellar vermis (B, C, D), and paravermian superior cerebellum (D). All the lesions represent high SIs on the DWI (E-H). ENZYMES USING THIAMINE AS COENZYME: - Pyruvate dehydrogenase Transketolase Xanthine dehydrogenase uses vitamin B2 as cofactor. Transaminases and decarboxylases use vitamin B6 as cofactor.
Pyruvate dehydrogenase
Transaminase
Xanthine dehydrogenase
Ornithine decarboxylase
Integrated QBank