Sickle cell anemia/disease case study

Nitrous oxide inactivates the enzyme methionine synthetase, and caution is urged in giving nitrous oxide to patients who may be deficient in vitamin B12. Low serum vitamin B12 concentrations have previously been reported in patients with sickle cell disease, but the reason for this is uncertain. Three cases of peripheral neuropathy have been reported in patients with sickle cell disease who received nitrous oxide (12-14). AU three had a history of frequent painful sickle crises, for which they received nitrous oxide for prolonged periods. Serum vitamin B12 concentrations were slightly reduced in two patients and very low in the third. The patients aU presented with difficulty in walking and paresthesia. Peripheral sensorimotor neuropathy was confirmed by nerve conduction studies. The patients all responded well to vitamin B12 injections and avoiding further exposure to nitrous oxide. Caution is therefore recommended when using nitrous oxide in patients with sickle cell disease or who are suspected of vitamin B12 deficiency. Two cases of polyneuropathy have also been reported after the use of nitrous oxide for 80 minutes and 3 hours in patients who were subsequently found to have pernicious anemia. They both responded well to hydroxocobalamin. 

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