TOPIC DISCUSSION: METHANOL and TOXIC EFFECTS

A nice feature in AJKD , the acid base teaching case this month presents the lack of toxic effects of methanol in someone with HIV.  Why does that matter? Like detectives, they figured this out in this case.  Methanol toxicity usually presents with anion gap and an osmolar gap.  The levels of methanol might take some time to come back but the AG is what you want to aim for. But in this case, there was no anion gap noted with this methanol ingestion.  Without a clinical history, this overdose can be overlooked especially, if there is an inhibitor of alcohol dehydrogenase present already doing its job such as ethanol.
Certain populations express lower levels of endogenous alcohol dehydrogenase :- infants, young women, cirrhotic patients, and certain racial groups.
Ethanol ingestion, or other alcohol such as isopropanol can competitively inhibit the metabolism of methanol and give this false impression of no methanol on board
Medications that can block this enzyme can also do it- fomepizole and in this case they presented was abacavir.

Great case and nice review of methanol kinetics and metabolism and the role of dialysis in removal of the toxin.