Lethal late onset cblB methylmalonic aciduria.

Abstract

To alert the physicians to the possibility of a late-onset inborn error of metabolism in an apparently previously healthy patient with acute clinical presentation. Case report. Pediatric unit and general intensive care unit. An apparently previously healthy 12-yr-old female presented acutely with vomiting, fever, bronchopneumonia, and progressive loss of consciousness associated with ketoacidosis, hyperglycemia, and hyperammonemia. She died 3 days later with a diagnosis of insulin-dependent diabetes mellitus. Intravenous hydration, glucose and insulin, mechanical ventilation. Organic acid analysis on a postmortem sample of aqueous humor revealed high levels of methylmalonic acid. Enzymatic studies on cultured fibroblasts were consistent with the diagnosis of cblB methylmalonic aciduria. The diagnosis of cblB methylmalonic aciduria was made in a postmortem patient who died with a misdiagnosis of insulin-dependent diabetes mellitus. Unclear biochemical findings and positive family history should strongly lead to suspicion of an inborn error of metabolism in an apparently previously healthy critically ill patient.