Neuroleptic malignant syndrome with abnormally elevated cardiac troponin I: a case report

Neuroleptic malignant syndrome (NMS) is a life-threatening neurological emergency that is primarily characterized by altered consciousness, hyperpyrexia, muscular rigidity, and autonomic instability. Here, we describe a unique case of NMS. A 54-year-old woman with major depressive disorder (MDD) was admitted to our hospital to relieve painful emotions; her laboratory tests and physical examinations were unremarkable. Her medication regime was as follows: day 1, quetiapine (200 mg), clonazepam (2 mg), and zopiclone (7.5 mg); day 2, olanzapine (5 mg) and sertraline (100 mg); day 3, olanzapine (15 mg), sertraline (100 mg), zopiclone (7.5 mg), and clonazepam (2 mg); day 4, olanzapine (15 mg) and haloperidol (5 mg); and day 5, sertraline (50 mg) and olanzapine (5 mg). The patient then developed NMS, and a series of tests showed further abnormalities. Unusually, her cardiac troponin I (TNI) was abnormally elevated as her NMS symptoms worsened, but gradually decreased after she was transferred to the cardiology department for treatment. The increased TNI was suspected to be related to the NMS. Here, we provide several potential explanations for the relationship between TNI and NMS. Based on the present case, it may be important to measure and monitor TNI concentrations in NMS patients.