Management challenges in delirium in genetically confirmed long QT syndrome: a case report and discussion

Treating delirium in adolescents with congenital long QT syndrome (LQTS) demands agents that do not aggravate ventricular repolarisation. A 15-year-old girl with genetically confirmed LQT1 and newly diagnosed acute lymphoblastic leukaemia developed hyperactive delirium in the paediatric intensive care unit after sepsis, abdominal surgery and prolonged sedation. Baseline manually calculated QTc in lead II was 533 ms (Bazett), 500 ms (Framingham), and 489 ms (Fridericia). Standard antipsychotics were avoided owing to torsadogenic risk. Low-dose aripiprazole (2 mg p.o. initially, up to 2 mg every 2 h as needed) was introduced, with twice-daily 12-lead ECGs. Agitation resolved within 48 h; QTc fluctuated between 460 and 490 ms (all three formulas) without ventricular arrhythmia. Serial serum aripiprazole levels were monitored for toxicity during intermittent dosing (cumulative dose 42 mg over 6 days). No extrapyramidal or haemodynamic adverse effects occurred, and aripiprazole was discontinued after a further 8 days.

This case illustrates a structured approach to delirium in adolescent LQTS and supports aripiprazole as a pragmatic option when QT-prolonging antipsychotics are contraindicated.