If a patient presents with advanced beriberi, and their pyruvate dehydrogenase complex is severely impaired, which downstream metabolic consequence most likely explains the neurological symptoms?

💡 Explanation

Impaired pyruvate dehydrogenase, due to thiamine deficiency in beriberi, disrupts the conversion of pyruvate to acetyl-CoA. Because this limits the substrate available for the Krebs cycle and subsequent ATP production, this leads to reduced cerebral ATP, rather than increased fatty acid synthesis which requires acetyl-CoA.

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