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Published on: June 20, 2018
Profound metabolic acidosis and oxoprolinuria in an adult
Michael J Hodgman1, James F Horn, Christine M Stork
1Bassett Healthcare, Cooperstown, NY, USA. hodgmanm@upstate.edu <hodgmanm@upstate.edu>
Introduction:
Profound metabolic acidosis in critically ill adults sometimes remains unexplained despite extensive evaluation.
Case Report:
A 58-year-old female presented in a confused state to the emergency department; she had been confused for several days. Laboratory evaluation revealed a high anion gap metabolic acidosis and modestly elevated acetaminophen level. Lactic acid was only modestly elevated. There was no evidence of ketoacids, salicylate, methanol, or ethylene glycol. A urine sample submitted on day 1 of hospitalization revealed a markedly elevated level of 5-oxoproline.
Discussion:
Originally described in children with an inherited defect of glutathione synthetase, 5-oxoproline is an unusual cause of metabolic acidosis. More recently this disturbance has been recognized in critically ill adults without a recognized inherited metabolic disorder. In most of these cases there has been the concomitant use of acetaminophen. Any causal relationship between acetaminophen and this disturbance is speculative.
Conclusion:
In critically ill adults with unexplained metabolic acidosis, 5-Oxoproline should be considered in the differential.
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