I don't see how at any point a person can be so deprived of nutrients brain convulsions occur. Something had to be wrong before hand, maybe he should get his wife's side of the story.
Thiamine (B1) deficiency can cause exactly that. It leads to mitochondrial disfunction depriving high-energy cells (mostly neurons) from ability to consume glucose via oxidation. As the result, a person develops insulin resistance that causes a swarth of consequences like an induced type 2 diabetes. If the situation with thiamine deficiency is not getting fixed, lactic acidosis proceeds as a dangerous side-effect of the backup metabolism path (anaerobic glycolysis) and gradually leads to progressive peripheral neuropathy including panic attacks (false hypoglycemia), burning sensations and numbness in the limbs and so on with ongoing neuro-degeneration.
Not sure if this is the author's situation but he should be very warned.
