Microarray analysis in children with developmental disorder or epilepsy.

The technique of chromosomal microarray analysis identifies genetic imbalance. Evaluation of its diagnostic role in pediatrics is still underway. We describe our experience with chromosomal microarrays. We retrospectively reviewed the charts of children in the Sections of Neurology and Clinical Genetics at St. Christopher's Hospital for Children who had undergone microarray analysis between 2006 and 2009. Collected data included age, sex, and the presence of mental retardation, developmental delay, autism, learning disability, hypotonia, dysmorphic features, and epilepsy, and the use of microarray technique. Statistical analysis was performed using SPSS. There were 82 children (mean age ± S.D., 5.7 ± 5 years), including 45 (55%) boys and 37 (45%) girls. All patients exhibited a normal karyotype. Microarray analysis produced abnormal results in 20 (23.5%). Deletions comprised 74% of all abnormalities. Patients with ≥ 4 clinical variables demonstrated a 30.5% incidence of abnormal chromosomal microarray findings, compared with 8.7% of patients with ≤ 3 clinical variables (P = 0.039, χ(2) test). Logistic regression indicated that motor impairment (P = 0.039) and presence of epilepsy (P = 0.024) independently contributed to the model. The likelihood of an abnormal microarray result increased with the number of clinical abnormalities. Microarray analysis will likely become the diagnostic genetic test of choice in children with neurodevelopmental disorders or epilepsy.

Efficacy and tolerability of topiramate in pediatric migraine.

About 5-10% of school-age children manifest migraine headaches. Treatment options for pediatric migraine are limited. Topiramate is approved for migraine prophylaxis in adults, but its use in children is limited. We retrospectively reviewed the records of 37 patients, i.e., 22 (60%) girls and 15 (40%) boys (mean age, 14 years; range, 7.3-20.5 years), diagnosed with migraine without aura in 30 (81%), with aura in four (11%), and abdominal, ophthalmoplegic, and catamenial in one each. The mean follow-up was 12 +/- 5 months standard deviation (S.D.). Clinical response was qualified as excellent, good, no change, or worse. Numbers of headaches per month were 15 +/- 7 S.D. prior to treatment and 3 +/- 3.4 S.D. (P < 0.001) after treatment. An excellent or good response (>50% migraine reduction) was attained in 28 patients (76%). Ten (27%) patients exhibited adverse effects. Patients taking >2 mg/kg/day were more likely to demonstrate side effects. The mean dose for patients without adverse effects was 1.27 +/- 0.7 mg/kg/day S.D. Those who reported adverse effects were taking a mean dose of 2.8 +/- 1.5 mg/kg/day S.D. This study demonstrated that topiramate is an effective, safe alternative for the prophylaxis of pediatric migraine. An acceptable risk/benefit maintenance dose was < or =2 mg/kg/day.

Efficacy and safety of lamotrigine monotherapy in children and adolescents with epilepsy.

Lamotrigine (LTG) has shown to confer broad-spectrum, well-tolerated control of epilepsy. Monotherapy is preferable over polytherapy because of better compliance, fewer adverse events, less interactions, lower teratogenicity and lower cost. The aim of this study is to evaluate the efficacy and safety of LTG monotherapy on seizure control in a cohort of children and adolescents with epilepsy. We retrospectively reviewed the records of children and adolescents treated with LTG monotherapy at our institution between 2001 and 2006. Data collected included demographics, seizure type, etiology of seizures, age at onset of seizures and at initiation of LTG treatment, number of antiepileptic drugs (AEDs) prior to LTG, dose of LTG, length of follow-up, treatment response, and adverse events. Seventy-two children and adolescents were identified (mean age 12.1 years); 37.5% had mental retardation. Age at onset of epilepsy was 5.7 years (0-16). Twenty three percent had symptomatic focal epilepsy, 15.5% idiopathic focal epilepsy, 19.4% symptomatic generalized epilepsy and 41.6% idiopathic generalized epilepsy. LTG was used as first-line monotherapy in 26.4% of patients and as a second-line monotherapy in 73.6%. Age at initiation of LTG therapy was 10 years (2.8-19). Mean number of AEDs tried prior to LTG was 1.3 (0-6). Mean dose of LTG was 5.5mg/kg/day (1.1-13.7). Mean follow-up period was 33 months (3 weeks to 11.5 years). The degree of seizure reduction was as follows: seizure free in 42%, 75-90% reduction in 17.4%, 50-74% in 11.6%, 25-49% in 10%. Sixteen percent had no change in seizure control and 3% became worse. The most common adverse event was rash (6.9%). Six (8.3%) patients discontinued LTG because of the adverse events. No patient had Stevens-Johnson syndrome. In conclusion, LTG was effective and well-tolerated as monotherapy in children and adolescents for both focal and generalized epilepsies.

Spinocerebellar ataxia type 7 mimicking Kearns-Sayre syndrome: a clinical diagnosis is desirable.

Spinocerebellar ataxias are a group of autosomal dominant cerebellar degenerative disorders, which are characterized by clinical and genetic variability. Spinocerebellar ataxia type 7 (SCA7) is less variable in clinical presentation than other SCAs. We present a pediatric patient with 13 and 70 trinucleotide CAG repeats within SCA7 gene and no family history, whose presentation mimicked Kearns-Sayre syndrome (KSS). We review the differential diagnosis of cerebellar ataxia with vision loss secondary to retinal pigmentary dystrophy. This paper supports concept of a desirable clinical diagnosis to avoid multiple genetic or invasive testing in children with neurodegenerative disorders.

Oxcarbazepine monotherapy in children and adolescents: a single-center clinical experience.

This single-center analysis evaluated the efficacy of oxcarbazepine monotherapy in children and adolescents. A retrospective chart review identified 60 patients (male=33, female=27) aged 6 months to 17.8 years (mean age 8.2+/-4.7 years) with partial onset epilepsy receiving oxcarbazepine monotherapy. The range of oxcarbazepine dose was 6-71 mg/kg/day (mean 26.3+/-11.4 mg/kg/day). The duration of therapy ranged from 3 months to 8 years (mean duration 16.7+/-14.3 months). Fifty-one patients (85%) achieved>or=50% reduction in seizure frequency, and 25 of 60 patients (42%) achieved seizure freedom. Ten patients (16.67%) reported adverse events including drowsiness, aggressive behavior, ataxia, dizziness, diplopia, and leg cramps. No hyponatremia or skin rash was observed. Twenty-four patients were switched from carbamazepine to oxcarbazepine monotherapy. In these patients carbamazepine was discontinued because of incidence of adverse events, poor seizure control, or both. Seventy-nine percent of patients switched from carbamazepine to oxcarbazepine monotherapy had >or=50% reduction in seizure frequency, and 37.5% became seizure-free. These findings suggest that oxcarbazepine monotherapy is effective and well tolerated in children and adolescents with partial epilepsy.

A PLP splicing abnormality is associated with an unusual presentation of PMD.

We report that a deletion of 19 base pairs (bp) in intron 3 of the proteolipid protein (PLP/DM20) gene causes a neurological disease characterized by mild developmental delay, followed by progressive decline of acquired motor and cognitive milestones. The clinical features are associated with mild delay in myelination demonstrated by magnetic resonance imaging studies and with ongoing demyelination and axonal loss demonstrated by magnetic resonance spectroscopy. We demonstrate that the purine-rich 19bp element regulates PLP-specific splice site selection in transient transfections of chimeric constructs into cultured oligodendrocytes. Runs of 4 and 5 Gs centered in the 19bp element are critical for efficient PLP-specific splicing. The intronic element is sequence specific in oligodendrocytes and is not a repressor of PLP-specific splicing in nonglial cells. These data support the conclusion that deletion of the 19bp purine-rich region in PLP intron 3 causes a reduction in PLP message and protein, which affects myelin stability and axonal integrity.