Abstracts

Rationale:
Neuroleptic Malignant syndrome (NMS) is a life-threatening neurological emergency, characterized by change of mental status, rigidity, fever and dysautonomia. It is associated with the use of antipsychotic medications. Early diagnosis helps guiding treatment and impacts the clinical outcomes. Here, we present a case of NMS which presented with non-convulsive epilepticus status (NCES).
Method:
A 62-year-old male with history of schizophrenia and no previous history of epilepsy, traumatic brain injury or stroke, presented with unresponsiveness. In the Emergency Department, he was stuporous with muscular rigidity, and noted to have fever, tachycardia and leukocytosis. After initial treatment, he was more awake and able to move all four extremities. However, he remained somnolent with profound generalized rigidity. CT head was unremarkable. Given fever and acute change in mental status, meningitis and non-convulsive status were suspected. Stat EEG was obtained and demonstrated NCSE, which resolved after receiving 4 mg of intravenous Lorazepam. He was also started on Brivaracetam 100 mg every 12 hours and was monitored with continuous video EEG (VEEG). Despite resolution of non-convulsive status, his mental status and generalized rigidity remained unchanged. On further review of his chart, he was found to take Ziprasidone at home. His Creatine Kinase (CK) was 9913 [iU]/L (with reference range of 17-193) and urine myoglobin was 93 mg/L (with reference range of 0-1). The significant elevation of CK and myoglobin was highly suspicious for NMS. Meanwhile, nuchal rigidity was difficult to assess due to generalized spasticity, and antibiotics were broadened to cover for possible meningitis with Vancomycin and Ceftriaxone. VEEG showed left frontal slowing, thus MRI brain was obtained to rule out focal lesions and acute cerebrovascular events, which turned out to be negative.
Results:
Ziprasidone was discontinued, and the patient was started on aggressive hydration. His mental status and rigidity significantly improved on the second day of admission.  Given improvement of mental status and resolving leukocytosis, lumbar puncture was not performed.
Conclusion:
Incidence of NMS ranges from 0.02 to 3 percent among patients taking antipsychotic medications and the mechanism of NMS remains unclear. It can occur even after several years on the same regimen. NMS can present with new onset seizure. It is rare for patients with NMS to present with NCSE. If patient presents with signs of NMS with impairment of mental status, NCSE should be considered.
Funding:
:No funding