title: Valproic acid-induced encephalopathy in very long course treated patients.
abstract: OBJECTIVE
  In patients receiving valproate (VPA) treatment, valproate induced-encephalopathy (VIE) is among the most serious adverse side-effects and hyperammonaemia is a frequent and well-recognized event. This report evaluates adult patients receiving VPA for several years.
  
  
  METHODS
  This study was conducted in adult patients receiving VPA for several years. Many studies have evaluated blood ammonia levels and VPA-related encephalopathy in patients whose treatment was initiated for a few months. Most studies were conducted in children.
  
  
  METHODS
  This study looked at retrospectively occurrences of VIE in 63 patients who were receiving VPA for a minimum duration of at least 2 years. At the beginning of the study basal ammonaemia was measured for all patients.
  
  
  RESULTS
  This study reports a rather frequent onset of VIE. Long duration of VPA treatment was not correlated with encephalopathy onset. In seven cases temporary administration of lactulose alone was effective and VPA was continued.
  
  
  CONCLUSIONS
  This study confirms that, under VPA treatment, hyperammonaemia is a current event; 25.4% patients presented isolated elevated ammonaemia when receiving VPA for very long durations. VPA therapy should be monitored closely and clinicians must be warned of VPA encephalopathy signs.
authors.affiliation: Hôpital San Salvadour (Assistance Publique Hôpitaux de Paris), Hyères cedex, France. marie-christine.rousseau@ssl.aphp.fr
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Rousseau
authors.forename: Marc
authors.initials: M
authors.lastname: Montana
authors.forename: Philippe
authors.initials: P
authors.lastname: Villano
authors.forename: Anne
authors.initials: A
authors.lastname: Catala
authors.forename: José
authors.initials: J
authors.lastname: Blaya
authors.forename: Maria
authors.initials: M
authors.lastname: Valkov
authors.forename: Yves
authors.initials: Y
authors.lastname: Allouard
authors.forename: Estelle
authors.initials: E
authors.lastname: Bugni
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000009:adverse effects*; D001925:Brain Damage, Chronic / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006501:Hepatic Encephalopathy / Q000139:chemically induced*; D006801:Humans; D022124:Hyperammonemia / Q000139:chemically induced*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014635:Valproic Acid / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D014635:Valproic Acid