title: Urea cycle disorders: a life-threatening yet treatable cause of metabolic encephalopathy in adults.
abstract: Urea cycle disorders are inborn errors of metabolism that, in rare cases, can present for the first time in adulthood. We report a perplexing presentation in a woman 4 days postpartum of bizarre and out-of-character behaviour interspersed with periods of complete normality. Without any focal neurological signs or abnormality on initial investigations, the diagnosis became clear with the finding of a significantly elevated plasma ammonia level, just as she began to deteriorate rapidly. She improved following intravenous dextrose and lipid emulsion, together with sodium benzoate, arginine and a protein-restricted diet. She remains well 12 months later with no permanent sequelae. Whilst this is a rare presentation of an uncommon disease, it is a treatable disorder and its early diagnosis can prevent a fatal outcome.
authors.affiliation: Department of Neurology, Royal North Shore Hospital, Sydney, Australia.
authors.forename: Nicholas F
authors.initials: NF
authors.lastname: Blair
authors.affiliation: Department of Neurology, Royal North Shore Hospital, Sydney, Australia.
authors.forename: Philip D
authors.initials: PD
authors.lastname: Cremer
authors.affiliation: Adult Genetic Metabolic Disorders Service, Westmead Hospital, Sydney, Australia.
authors.forename: Michel C
authors.initials: MC
authors.lastname: Tchan
mesh_terms: D000328:Adult; D000641:Ammonia / Q000097:blood; D001120:Arginine / Q000627:therapeutic use; D001928:Brain Diseases, Metabolic / Q000209:etiology*; D018753:Diet, Protein-Restricted; D005217:Fat Emulsions, Intravenous / Q000627:therapeutic use; D005260:Female; D005947:Glucose / Q000627:therapeutic use; D006801:Humans; D049590:Postpartum Period; D020160:Sodium Benzoate / Q000627:therapeutic use; D056806:Urea Cycle Disorders, Inborn / Q000150:complications*
chemical_list: D005217:Fat Emulsions, Intravenous; D000641:Ammonia; D001120:Arginine; D005947:Glucose; D020160:Sodium Benzoate
keywords: Encephalopathies, Metabolic; Hyperammonemia; Ornithine Carbamoyltransferase Deficiency Disease; Postpartum Period; Urea Cycle Disorders, Inborn