title: [Valproate-associated hyperammonemic encephalopathy. Report of one case].
abstract: Valproate can be associated to hyperammonemic encephalopathy, characterized by fluctuating sudden-onset alterations of sensorium, focal symptoms and an increase in the frequency of seizures. We report a 78 year-old female using valproate 1,000 mg/ day for 10 months for the treatment to tonic-clonic seizures. She was admitted on three occasions in the last fourth months for self limited clouding of sensorium. Laboratory, imaging and electroencephalographic studies were non-contributory Blood ammonia levels were 123 microg/dl (normal: 15-50 microg/dl). Due to the possibility of a hyperammonemic encephalopathy secondary to valproate, the drug was discontinued and she was treated with lactulose and intravenous L-carnitine, 1 g/day The patient showed a complete recovery within 48 hours. This drug-associated encephalopathy is a reversible but potentially fatal cause, probably underdiagnosed, that requires a high index of suspicion.
authors.affiliation: Servicios de Clínica Médica y Nefrología, Hospital Británico de Buenos Aires, Perdriel 74, Argentina. pabloyoung2003@yahoo.com.ar
authors.forename: Pablo
authors.initials: P
authors.lastname: Young
authors.forename: Bárbara C
authors.initials: BC
authors.lastname: Finn
authors.forename: Florencia
authors.initials: F
authors.lastname: Alvarez
authors.forename: Julio E
authors.initials: JE
authors.lastname: Bruetman
authors.forename: Hernán
authors.initials: H
authors.lastname: Trimarchi
mesh_terms: D000368:Aged; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D001927:Brain Diseases / Q000139:chemically induced* / Q000175:diagnosis; D005260:Female; D006801:Humans; D022124:Hyperammonemia / Q000139:chemically induced* / Q000175:diagnosis; D014635:Valproic Acid / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D000927:Anticonvulsants; D014635:Valproic Acid