The deficiency of which vitamin is associated with Wernicke-Korsakoff syndrome?

• A. Vitamin B1
• B. Vitamin B2
• C. Vitamin B3
• D. Vitamin B9

Answer: (A)

Thiamine (vitamin B1) deficiency is linked to Wernicke-Korsakoff syndrome. This condition arises when the brain cannot generate enough energy because thiamine is a crucial cofactor for enzymes in glucose metabolism, including pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase. When thiamine is scarce, brain cells, which rely heavily on glucose for energy, struggle to produce ATP, leading to neuronal injury, especially in areas like the mammillary bodies and thalamus. The resulting clinical picture starts with acute Wernicke symptoms such as eye movement abnormalities, ataxia, and confusion, and can progress to Korsakoff syndrome, characterized by profound memory deficits and confabulation. Prompt thiamine replacement is essential, and glucose administration should be given after thiamine to avoid precipitating or worsening the deficiency’s effects. Other vitamins listed do not cause this syndrome; deficiencies in B2, B3, or B9 are associated with different clinical conditions.