Successful treatment of six patients with neuroleptic malignant syndrome associated with myoglobulinemic acute renal failure.

Neuroleptic malignant syndrome is a rare but potentially lethal, rare reaction to neuroleptics which is characterized by altered levels of consciousness, extrapyramidal effects, autonomic instability, hyperthermia, and elevated serum creatine phosphokinase levels. The most serious complication of neuroleptic malignant syndrome is acute renal failure. We investigated six cases of neuroleptic malignant syndrome associated with myoglobulinemic acute renal failure due to rhabdomyolysis and effect of hemodialysis or hemodiafiltration. The patients were five males and one female with a mean age of 43.5 yr. All of the patients, who developed acute renal failure induced from rhabdomyolysis, had previously received butyrophenone (haloperidol), phenothiazine, benzamide, iminomide, benzisoxazole, antidepressants, and hypnotics (benzodiazepine and barbiturate) for the treatment of schizophrenia. The clinical manifestations of neuroleptic malignant syndrome were characterized by altered consciousness, muscle rigidity and weakness, fever, and excessive perspiration. The peak laboratory data were blood urea nitrogen 102 +/- 26 (mean +/- SD) mg/dL, serum creatinine 9.1 +/- 2.1 mg/dL, serum creatine phosphokinase 229,720 +/- 289,940 IU/L, and all of them developed oliguric acute renal failure. Dantrolene sodium administration was given to five cases and hemodialysis or hemodiafiltration was performed in all of them. The serum creatinine level after hemodialysis or hemodiafiltration was 1.4 +/- 1.0 mg/dL. All patients were successfully cured of acute renal failure by hemodialysis or hemodiafiltration. As a result, myoglobulinemic acute renal failure associated with neuroleptic malignant syndrome was successfully treated by hemodialysis or hemodiafiltration.