Thiamine deficiency can lead to which condition?

• A. Korsakoff syndrome
• B. Beriberi
• C. Wernicke encephalopathy
• D. Guillain-Barré syndrome

Answer: (C)

Thiamine (vitamin B1) is essential for brain energy metabolism, so when it's deficient the nervous system is affected early and acutely. Wernicke encephalopathy is the immediate brain-related manifestation of thiamine deficiency, presenting typically with acute changes such as confusion, problems with eye movements, and impaired coordination or gait. This makes it the best answer because it directly reflects the brain dysfunction caused by insufficient thiamine. If thiamine deficiency continues untreated, it can progress to Korsakoff syndrome, a chronic memory disorder, but that is a later development rather than the initial acute presentation. Beriberi refers to peripheral nerve and cardiovascular manifestations, not the acute brain involvement. Guillain-Barré syndrome is an autoimmune neuropathy unrelated to thiamine deficiency.