Reversible nitrous oxide-induced myeloneuropathy with pernicious anemia: case report and literature review.

A previously healthy 27-year-old woman developed a subacute myeloneuropathy after receiving nitrous oxide anesthesia for dental procedures. Neurologic evaluation revealed that she was vitamin B(12) deficient due to underlying pernicious anemia. Discontinuation of nitrous oxide and supplementation with vitamin B(12) resulted in dramatic clinical improvement, with near-complete normalization of her neurologic examination. This case and published reports reviewed here emphasize that favorable outcomes are possible following prompt recognition and treatment of vitamin B(12) deficiency.