Neuroleptic malignant syndrome secondary to olanzapine, a presentation with severe acute kidney injury requiring hemodialysis: a case report

BACKGROUND: We present this case to draw attention to the importance of early diagnosis in terms of life-saving, noting that greater awareness is important among healthcare professionals. Our patient developed neuroleptic malignant syndrome (NMS) after his neuroleptic drug dosage was increased. His condition was complicated by acute kidney injury (AKI) which required hemodialysis. The uniqueness of this case is that the causative agent of NMS is an atypical antipsychotic, and atypical antipsychotics are generally considered to be safer than typical antipsychotics. CASE PRESENTATION: A 31-year-old Chinese man with underlying schizophrenia presented to our hospital with aggressive behavior. He was admitted to the psychiatric hospital and started on his regular medications, with an increase in the dose of olanzapine tablet from 5 to 10 mg daily. After 5 days in the ward, the patient was noted to have high fever, restlessness, confusion, increased muscle rigidity, tachycardia and tachypnoea. Antipsychotic therapy was stopped in view of suspected NMS. The first laboratory test for serum creatine kinase (CK) showed a markedly high level of this molecule. His renal profile showed raised serum creatinine in comparison to 2 months prior when the baseline serum creatinine was within the normal range. A diagnosis of NMS with AKI was made. Although the patient was given adequate intravenous fluid hydration with close monitoring of urine output, his renal function did not show improvement but continued to show a worsening trend. In view of this, he was started on urgent hemodialysis. The patient was dependent on intermittent hemodialysis before his AKI showed complete recovery. After 2 weeks, his blood test results returned to normal. He was discharged well. CONCLUSION: Neuroleptic malignant syndrome is a life-threatening iatrogenic medical emergency in which high index of clinical suspicion is required for diagnosis and prompt treatment.