title: Postchemotherapy hyperammonemic encephalopathy emulating ornithine transcarbamoylase (OTC) deficiency.
abstract: A young patient with hepatocellular carcinoma receiving chemotherapy presented with encephalopathy. Evaluation of the patient revealed a metabolic profile consistent with ornithine transcarbamoylase (OTC) deficiency, an inherited disorder of the urea cycle. The evaluation yielded a plasma amino acid analysis consistent with OTC deficiency. However, genetic analysis did not reveal a somatic mutation of the OTC gene in this patient. The hyperammonemic encephalopathy was reversed by the infusion of arginine, a common treatment for hereditary OTC deficiency. This case may represent a distinct syndrome of reversible hyperammonemia in patients with hepatocellular carcinoma.
authors.affiliation: Division of Hematology and Medical Oncology and Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Chan
authors.forename: Cary O
authors.initials: CO
authors.lastname: Harding
authors.forename: Charles D
authors.initials: CD
authors.lastname: Blanke
mesh_terms: D000328:Adult; D001120:Arginine / Q000097:blood / Q000627:therapeutic use; D006528:Carcinoma, Hepatocellular / Q000150:complications* / Q000188:drug therapy; D002956:Citrulline / Q000097:blood; D005260:Female; D005973:Glutamine / Q000097:blood; D006501:Hepatic Encephalopathy / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D006801:Humans; D022124:Hyperammonemia / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D008113:Liver Neoplasms / Q000150:complications* / Q000188:drug therapy; D009952:Ornithine / Q000097:blood; D020163:Ornithine Carbamoyltransferase Deficiency Disease / Q000175:diagnosis* / Q000235:genetics; D009963:Orotic Acid / Q000652:urine; D018807:Polymorphism, Single-Stranded Conformational; D013577:Syndrome
chemical_list: D005973:Glutamine; D002956:Citrulline; D009963:Orotic Acid; D001120:Arginine; D009952:Ornithine