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

Abstract

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.

Developmental Differences in Acute Nigrostriatal and Mesocorticolimbic System Response to Haloperidol

“…These observations may have some relationship to clin ical observations that indicate that children may be at relatively high risk for developing neuroleptic malig nant syndrome (NMS) during neuroleptic treatment. In children less than 6 years of age, almost all reported cases of NMS occurred after ingestion of only a single dose of neuroleptic (Latz and McCracken 1992). The fa tality rate from NMS was 13% among adolescent pa tients with NMS (n = 38), and 33% in patients 12 years or younger (n = 11) (Latz and McCracken 1992).…”

“…In children less than 6 years of age, almost all reported cases of NMS occurred after ingestion of only a single dose of neuroleptic (Latz and McCracken 1992). The fa tality rate from NMS was 13% among adolescent pa tients with NMS (n = 38), and 33% in patients 12 years or younger (n = 11) (Latz and McCracken 1992).…”

Neuroleptic Malignant Syndrome in Children and Adolescents: Time to Stop, Look, and Listen

“…There appear to be two dramatically different outcomes of NMS in children and adolescents: complete recovery or death. In their series of 49 cases, Latz and McCracken (1992) found that 16% of patients died. Of the 35 cases reviewed by Steingard and colleagues (1992), 14% died.…”

“…In their case report, Steingard et al describe a 16-year-old who developed the cardinal symptoms and signs of NMS: altered mental status (e.g., agitation, disorientation), fever, increased muscle tone or rigidity, autonomie instability (e.g., elevated blood pressure), leukocytosis, elevated creatinine phosphokinase (CPK) levels, and abnormal liver function studies [e.g., elevated levels of enzymes such as serum glutamic oxaloacetic transaminase (SGOT)]. Latz and McCracken (1992) reported on two adolescents, ages 15 and 16 years, who presented with a classical symptom constellation. Neither group found evidence of a different presentation of NMS in younger children.…”

“…Using a computerized search to locate all available English language references, Steingard et al (1992) identified 35 cases (including their own) of NMS in children and adolescents below age 19 years. Using a similar procedure, Latz and McCracken (1992) found a total of 49 cases. These cases have been reported in the medical literature over the last 20 years.…”