Neuroleptic Malignant Syndrome with Suspected Lithium Toxicity Following Combined Lithium and Antipsychotic Overdose, Complicated by Rhabdomyolysis and Fatal Acute Kidney Injury: A Case Report

Abstract

Neuroleptic malignant syndrome (NMS) and lithium toxicity are life-threatening complications of psychotropic medication exposure with substantially overlapping clinical manifestations, potentially delaying recognition when they occur together. We report a fatal case of a 40-year-old man with bipolar affective disorder who presented seven days after intentional ingestion of lithium, lorazepam, olanzapine, divalproex, and quetiapine. He developed persistent high-grade fever, altered sensorium, generalised rigidity, seizures, respiratory failure, rhabdomyolysis, stage 3 acute kidney injury (AKI), hyperkalaemia, transaminitis, and mixed metabolic and respiratory acidosis. NMS with suspected concomitant lithium toxicity was diagnosed clinically. Management included immediate withdrawal of psychotropic agents, bromocriptine, aggressive hydration, active cooling, correction of electrolyte abnormalities, peritoneal dialysis followed by continuous renal replacement therapy (CRRT), and multidisciplinary care involving nephrology, neurology, and psychiatry. Despite treatment, the patient developed refractory hyperthermia, worsening acidosis, refractory hypotension, and cardiac arrest with pulseless ventricular tachycardia progressing to asystole. This case highlights the diagnostic overlap between NMS and lithium toxicity, the potentially catastrophic consequences of delayed presentation after deliberate self-poisoning, and the importance of early recognition and appropriate renal replacement therapy in critically ill patients with severe AKI.