High plasma branched-chain amino acids:aromatic amino acids ratio in children on the ketogenic diet: a mechanism in controlling epilepsy.

BACKGROUND: The authors proposed that ketogenic diets will produce an increase in the ratio of branched chain amino acids (BCAAs) and aromatic amino acids (BCAAs) in plasma of children who are on the diets. SUBJECTS AND METHOD: A sample of plasma amino acids sample before initiation of fasting and on day 10 of the dietary treatment was obtained in patients with refractory epilepsy who were newly admitted for initiation of ketogenic diet. Plasma amino acids were determined by high performance liquid chromatography equipment. RESULTS: There are 20 patients with refractory epilepsy participating in this study. Outcomes of ketogenic diet therapy were satisfactory. Nineteen cases out of 20 cases had a significantly higher ratio of plasma BCAAs:ARAAs during ketogenic diets than before the diet (P < 0.001). CONCLUSION: The ketogenic diets produced an increased ratio of plasma BCAAs:ARAAs. Whether the increased ratio of plasma BCAAs:ARAAs plays an important role in controlling epilepsy is yet to be elucidated.

Vigabatrin therapy in infantile spasms.

RATIONALE: To determine the clinical outcome and side effects of vigabatrin (VGB) in the treatment of infantile spasms (IS) and its long-term outcome. METHOD: All children with IS treated with vigabatrin were studied. Clinical data regarding age of onset, duration of IS before therapy started, recurrence of IS, types of seizures that relapse, clinical outcome and side effects were monitored. RESULTS: 36 children (17 girls, 19 boys) with IS participated in the study. The mean age of onset of IS was 115.55 +/- 67.3 days old (range, 15 to 300 days). Six were cryptogenic IS and 30 were symptomatic IS. The etiologies of symptomatic IS in this study were tuberous sclerosis, hypoxic ischemic encephalopathy (HIE)/periventricular leukomalacia, porencephaly, partial agenesis of corpus callosum, hemimegalencephaly, cortical dysplasia, and microcephaly. 66.67 per cent (24 of 36) of patients responded to VGB within a mean 2.95 +/- 2.25 days (range, 1 to 7 days). In those who responded to VGB, 3 patients developed recurrent IS within 69.3 +/- 46.7 days (range, 30 to 121 days). Five patients developed epilepsy with different types of seizure during long-term follow-up. The mean duration of subsequent epilepsy after cessation of IS was 16.4 months (range, 5 months to 3 years 10 months). The mean duration of follow-up was 2.74 years (range, 1.09 years to 5.76 years). 10 patients were successfully weaned off VGB after a mean IS free period of 22.5 +/- 5.5 months (range, 12 to 27 months). Transient drowsiness was seen in 4 patients. Three patients had transient abnormal sleep patterns and irritability. Visual field abnormalities were not found but difficult to assess fully in this study. CONCLUSION: VGB therapy has a high response rate for the control of IS and is well tolerated in most children. All patients who responded to VGB and were spasm free for more than one year were successfully weaned off VGB therapy. Because serious side effects such as visual field abnormalities are difficult to monitor, the authors propose that VGB could be withdrawn or switched to another AED after a spasm-free period of more than one year.

Childhood onset myasthenia gravis.

The authors share experiences in taking care of 27 cases of childhood onset myasthenia gravis (MGS). In all cases, the diagnosis was confirmed by a combination of clinical examination and Neostigmine test. The majority (92%) had localized ocular myasthenia with median onset of symptoms at 33 months of age. About 24 per cent of them progressed to generalized MGS. A few (8%) presented with respiratory failure that required ventilatory support with onset of symptoms at about 22 months. Thymectomy was performed in 10 cases. Complete and partial remissions were achieved in about 70 per cent and 26 per cent of cases respectively with the combination of an immunosuppressant (azathioprine) and a Cholinesterase inhibitor (pyridostigmine). None experienced a myasthenic crisis with proper management and good follow-up using the above combinations.