No abstract

Cerebrovascular disorders are more common than once suspected, and our ability to diagnose stroke in children has improved with the development of newer imaging techniques in recent years. Children have a wide array of risk factors that promote cerebral infarction or hemorrhage, and a likely cause can eventually be pinpointed in about two thirds of patients if a thorough diagnostic evaluation is performed. Ideally, a systematic evaluation should confirm the presence of a cerebrovascular lesion and also identify the cause, concentrating initially on the more common or treatable risk factors. Recognition of the cause of a child's stroke is important, because the likelihood of recurrence depends largely on the etiology and whether treatment is available.

To assess the clinical characteristics of valproate (VPA)-associated pancreatitis, information from three sources was gathered: (a) a survey among 507 physicians with a special interest in treatment of epilepsy, (b) a review of the authors' patient population, and (c) a review of the literature. Of 366 physicians answering the survey, 53 (14.5%) reported a case of pancreatitis. Thirty-nine cases were available for review (24 from the medical literature, 12 from the survey, and 3 from the authors). Pancreatitis appeared to be more frequent in young persons (mean age 16.4 years) but may occur at any age. The highest risk appears to exist during the first months of treatment: 43.8% of the cases developed during the first 3 months, and 68.8% developed during the first year. Seventy-six percent of patients were receiving polytherapy, and 41% had some form of associated chronic encephalopathy. In most patients, the reaction was rapidly reversible when VPA was discontinued. It was severe in 6 patients, with 3 deaths reported. Rechallenge with VPA was attempted in 9 patients, with a high incidence of relapses. Asymptomatic elevation of serum amylase in patients receiving VPA was reported by 40 (10.9%) of the physicians surveyed. Awareness of the problem and early discontinuation of VPA may be effective in preventing serious reactions.

Data from 50 patients with juvenile myoclonic epilepsy (JME) were analyzed retrospectively to assess the response to drug therapy--long-term seizure control, relapse rates, and confounding factors in seizure recurrence. Valproate is the only available antiepileptic drug that has been shown to be effective in controlling the generalized seizure components of JME--myoclonic, tonic--clonic, and absence seizures--without significant side effects. Data were collected using the EpiMonitor software and represented case follow-up from 2 months to 9 years. Forty-three patients (86%) were seizure free for at least 1 year; 25 patients (50%) relapsed at some point during follow-up. Relapses were precipitated most frequently by fatigue, noncompliance, stress, sleep deprivation, and alcohol consumption. With accurate diagnosis and appropriate therapy, seizures in JME can be adequately controlled, although JME is a chronic disorder that may require lifelong therapy. To minimize relapse, patient management must also focus on patient lifestyle to eliminate or control lifestyle-associated precipitants of seizure relapse.

We reviewed the frequency of valproate-induced thrombocytopenia in children with epilepsy in our institution. Sixty-four (21%) of 306 children taking valproate developed thrombocytopenia. Thirty-two of these 64 patients had at least one platelet count lower than 100 x 10(3)/mm3. Eight patients developed signs of bleeding. Low platelet levels were typically noted in patients with serum valproate levels of over 140 micrograms/mL, and reduction of the medication dose usually resulted in a prompt increase in the number of platelets. Only one patient developed thrombocytopenia unrelated to high serum drug levels, and her platelet count did not improve until the drug was discontinued. Neither the age of the patient nor the use of additional antiepileptic medication correlated with the platelet count. However, duration of valproate use was related. These data suggest that, although valproate may cause thrombocytopenia via more than one mechanism, by far the most common factor is the presence of high valproate levels. Thus, the medication can be safely lowered in most patients with thrombocytopenia rather than discontinued altogether. Platelet counts should probably be monitored more carefully in patients known to have higher drug levels.

The clinical and radiographic findings of 68 children and adolescents with nontraumatic intraparenchymal brain hemorrhage were analyzed retrospectively. There were 43 boys and 25 girls, and the average age was 7.1 years (range, 3 months to 18 years). The most common presenting symptom was a combination of headache or vomiting (40 cases, or 58.8%). Hemiparesis was the major presenting sign in 11 (16.2%) of the children, seizures occurred in 25 (36.8%) patients, and 6 (8.8%) children were irritable. Only 2 (2.9%) children were comatose at presentation. One or more risk factors for hemorrhage were found in 61 (89.7%) of 68 children. A third (23 cases, or 33.8%) had an arteriovenous malformation or fistula; altogether 29 (42.6%) children had some type of congenital vascular anomaly. Hematologic or coagulation disorders were present in 22 (32.4%) patients, and 9 (13.2%) patients had brain tumors. Hemorrhage could not be attributed to systemic hypertension in any child. The likelihood of establishing the cause of bleeding was greater when evaluation included cerebral angiography (97.3% versus 80.4% without angiography). Half (34 cases, or 50.0%) of the patients regained normal neurologic function. Six (8.8%) patients died, either directly or partly as a consequence of the hemorrhage. The remaining patients had various neurologic sequelae, including 17 (25.0%) with hemiparesis, 5 (7.4%) with aphasia, 7 (10.3%) with epileptic seizures, and 3 (4.4%) with hydrocephalus. More detailed follow-up studies are needed to obtain more information about the frequency of cognitive sequelae.

We report two children with hemisomatic spasms caused by neoplastic lesions in the region of the ipsilateral cerebellopontine angle. In this condition, seizure misdiagnoses are frequent and EEGs are normal, even ictally. MRI should be performed early to prevent delay of appropriate treatment.

We performed a randomized double-blind crossover therapeutic bioequivalency study of a generic (Epitol) versus a brand name (Tegretol) carbamazepine product under steady-state conditions in 40 epileptic patients. Each patient received 90-day supplies of Epitol or Tegretol and placebo, which replaced the usual dosage of the alternate product. Group A consisted of 20 seizure-free (from 5 months to 2 years) patients and group B of 20 patients with seizures refractory to drug therapy. In group A, four patients had seizures, two on both Epitol and Tegretol and two on Tegretol. In group B, the average seizure frequencies were 0.25 seizures per day on Epitol and 0.22 seizures per day on Tegretol. Average seizure frequencies were statistically the same (at a 20% difference, p less than 0.05). Areas under the curve were statistically the same (at a 20% difference, p = 0.05). Average peak heights were statistically the same (at a 20% difference, p less than 0.05). Average time to peak was earlier with Epitol. Epitol and Tegretol performed equally well in clinical efficacy and bioequivalency.