Valproate-induced Hyperammonemia Manifested with Delirium

Valproate-induced Hyperammonemia Manifested with Delirium

A 50-year-old female patient was diagnosed with bipolarI disorder. Her first depressive episode was in her teens, andfirst manic episode at 45 years of age. She was admitted toacute psychiatric ward for a manic episode presenting herselfwith mood liability, talkativeness, violence, and grandiosedelusions. The results of initial laboratory examinations wereall within normal limits.On admission day one, the patient received daily valproicacid (VPA) 1,000 mg, lorazepam 2 mg, and flurazepam 30 mg.VPA was uptitrated to 1,300 mg/day on day four in addition toher daily clotiapine 40 mg and chlorpromazine 50 mg whileher behaviors became more disturbing. With increased VPAdosage to 1,500 mg/day, her elated mood and grandiosity weregradually improved, but she started to develop confusion,disorganized behaviors, and aggravated daytime somnolence.Chlorpromazine was discontinued on day 14 and changedto olanzapine 5 mg/day. The laboratory data on day 19demonstrated to have normal serum liver enzymes but elevatedserum VPA level (124.1 mcg/mL) and hyperammonemia (111.3mcmol/L). VPA dosage was reduced from 1,500 to 1,300 mg/day. But her consciousness fluctuation and disorientationwere worsened with increasing serum VPA level (126.7mcg/mL) and hyperammonemia (434.9 mcmol/L). VPA wastotally discontinued on day 22, and she received emergencyfluid resuscitation. She received lactulose to eliminate thehyperammonemia.