Status epilepticus in children with epilepsy: the role of antiepileptic drug levels in prevention.
OBJECTIVE
To determine the association between subtherapeutic antiepileptic drug (AED) levels or AED withdrawal and status epilepticus (SE) in children with epilepsy.


METHODS
We studied the AED levels at the time of SE in 51 consecutive children with epilepsy. Information about prior AED levels, possible etiology of seizures, and acute precipitants was extracted from medical records.


RESULTS
The mean age at the time of SE was 5.7 years (range, 3 months through 18 years). Forty-three patients had history of remote insult, five had history of progressive encephalopathy, and three patients were classified as idiopathic. At the time of SE all AED levels were therapeutic in 34 (66%) patients and at least one level was therapeutic in 42 (82%) patients. All levels were subtherapeutic in 9 (18%) patients. Four patients had their AED reduced or discontinued less than 1 week before SE. Twelve patients with therapeutic AED levels on their most recent clinic visit had at least one subtherapeutic level at the time of SE. Eight (16%) patients were febrile and one was hyponatremic. Of the 51 patients, 31 (61%) had no obvious explanation for the development of SE, as all known AEDs were therapeutic and there were no known acute insults.


CONCLUSIONS
Neurologically abnormal children with preexisting epilepsy are at high risk for development of SE despite having therapeutic AED levels at that time. Acute precipitants of SE, such as fever or AED withdrawal, may play a role in inducing SE only in a minority of patients.
Maytal
J
J
Division of Pediatric Neurology, Schneider Children's Hospital, Long Island Jewish Medical Center, Albert Einstein College of Medicine, New Hyde Park, New York 11040, USA.
Novak
G
G
Ascher
C
C
Bienkowski
R
R
D000293:Adolescent; D000927:Anticonvulsants / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D013226:Status Epilepticus / Q000188:drug therapy* / Q000209:etiology / Q000517:prevention & control
D000927:Anticonvulsants