Neuroleptic Malignant Syndrome in Children and Adolescents: Two Case Reports and a Warning

Neuroleptic malignant syndrome (NMS) is a potentially fatal disorder associated with the use of neuroleptics. Clinical research on NMS to date has focused exclusively on adults, but increasing numbers of juvenile cases have been reported. Two cases of juvenile NMS treated by the authors are discussed to demonstrate early warning signs, possible contributory factors, and effective treatment strategies. Forty-nine reported cases of NMS in children and adolescents are then reviewed in order to assess frequency, possible risk factors, predictors of poor outcome, and effective treatment. The most common diagnosis is schizophrenia (35%) followed by bipolar disease (12%), schizoaffective disorder (8%), and mental retardation (8%). Over half the reported cases involve treatment with high potency neuroleptics (57%), compared to only 14% with low potency neuroleptics. The death rate in patients 18 years or younger is 16%. In adolescent patients, the death rate is 13%; this rate increases to 27% in patients 12 years or younger. A recent adult study, by contrast, estimates a mortality rate of only 4%. We conclude that NMS in children, may be underdiagnosed, and that failure to diagnose may contribute to relatively high juvenile mortality rates.