Ileus as a Sign of Neuroleptic Malignant Syndrome: A Case Report and Review of the Literature

Introduction: Neuroleptic malignant syndrome (NMS) is a rare and unpredictable adverse reaction associated with the use of first-generation and second-generation antipsychotics. Atypical antipsychotics may create atypical forms of NMS due to their different pharmacological characteristics. Decreased dopaminergic tone in the brain is coincided with a dysregulation of autonomic nervous system in this syndrome. This paper reports on an NMS case, in which current views and symptoms that occurred during the course of the disease were rare symptoms that are not usually found in NMS. Case Presentation: The patient was a 43-year-old male with schizoaffective disorder under treatment with clozapine and risperidone. He had lead pipe muscle rigidity, stupor, fever and autonomic dysfunction, increased levels of creatinine phosphokinase, leukocytosis, and microglobulina. Levenson’s criteria is widely accepted for diagnosis of NMS. Six days after admission to the psychosomatic ward, the patient had ileus. Due to lack of response to neomycin and GI rest and embedding NG tube, the patient underwent therapeutic sigmoidoscopy and colonoscopy for decompression. Conclusions: Diagnosis of NMS is largely based on clinical history and the presence of specific clinical symptoms. Antipsychotics polypharmacy increases the NMS risk. Mechanisms underlying the development of ileus in the patient are speculative and multifactorial. Paralytic ileus can be one of the autonomic dysfunctions in NMS. Furthermore, NMS is categorized in differential diagnosis of acute abdomen caused by the pseudo-obstruction. All physicians should be aware of this possibility when faced with patients under treatment with neuroleptics.