Augmented startle responses in opsoclonus-myoclonus syndrome.

We report a 3-year-old boy with opsoclonus-myoclonus syndrome (OMS) who presented with exaggerated startle responses to unexpected auditory stimuli during an episode of myoclonic status. An augmented blink reflex was also observed clinically and electrophysiologically. Based on the assumption that hyperexcitability in the lower pontine tegmentum may be responsible for the acoustic startle and blink reflex in OMS, we considered that increased excitability of independent but neighboring structures, including the pontine paramedian reticular formation, may cause OMS symptoms.

Thiamine-deficient encephalopathy due to excessive intake of isotonic drink or overstrict diet therapy in Japanese children.

AIM: To report on two children with encephalopathy caused by dietary thiamine deficiency due to newly developing nutritional problems in contemporary Japan. SUBJECTS: A 1-year-old boy who had consumed 1l of isotonic drinks per day for 4 months after an episode of diarrhea, and presented with ocular movement disorder, dystonia, and unconsciousness. The other subject was an 11-month-old boy who suffered from vomiting and somnolence; he and his mother had atopic dermatitis, and he had been on a low-allergen diet that strictly restricted intake of eggs, dairy products, meat, and fish since his early infancy. RESULTS: Both patients showed decreased blood thiamine levels and magnetic resonance imaging revealed striatal and thalamic lesions. Thiamine administration yielded prompt improvement of symptoms, but cavitiform lesions in the bilateral putamen persisted in the first patient, accompanied by residual generalized dystonia. Marked elevation of blood/cerebrospinal lactate levels and severe hyponatremia were present in this patient. CONCLUSION: Thiamine-deficient encephalopathy in Japanese children due to excessive intake of sports drink or overstrict diet therapy for atopic dermatitis has been increasingly reported during the last decade, but is still not broadly recognized. These children may visit hospitals due to persistent vomiting as a symptom of thiamine deficiency, but glucose infusion without thiamine supplementation can aggravate their condition. Knowledge of these facts in medical and public settings is necessary to correct the erroneous impression that nutritional options given to ill children are necessarily beneficial for health, and promote awareness that they can be harmful when consumed in excess.

[Three cases with severe motor and intellectual disabilities presenting the severest condition caused by prolonged non-convulsive status epilepticus].

Three patients with severe motor and intellectual disabilities presented deterioration of the activities of daily living, which was revealed to be caused by prolonged non-convulsive status epilepticus (NCSE). Their condition improved by the treatment with antiepileptics. Case 1, a 4-year-old girl with profound psychomotor retardation and past history of West syndrome of unknown etiology, became unable to sit and eat orally above age of two years. EEG showed continuous generalized slow spike and wave bursts indicating NCSE. Continuous intravenous infusion of midazolam abolished EEG abnormalities of NCSE, and she regained the ability of oral feeding. Case 2, a 3-year-old boy with Angelman syndrome and past history of West syndrome, presented decreased mental response, poor oral intake and somnolence. EEG showed continuous slow spike and wave bursts, indicating NCSE. High-dose phenobarbital therapy and continuous intravenous injection of vitamin B6 were effective, and remarkably improved his psychomotor activities. Case 3, a 3-year-old boy with Lennox-Gastaut syndrome, developed decreased psychomotor activity and loss of vocalization and walking. He could not sit by himself and became nearly bed-ridden. EEG showed very frequent generalized spike and wave bursts, showing NCSE. Continuous infusion of thiopental diminished NCSE, and he could walk again. Psychomotor deterioration in patients with severe motor and intellectual disabilities may be caused by NCSE, which should not be overlooked.

Oral high-dose phenobarbital therapy for early infantile epileptic encephalopathy.

We report oral high-dose phenobarbital therapy for a patient with early infantile epileptic encephalopathy with suppression bursts (Ohtahara syndrome). At 1 month of age, many series of tonic spasms, with raising limbs and crying lasting for a few minutes, developed and increased up to approximately 300 times per day. Initially intravenous midazolam (0.5 mg/kg/hour) slightly decreased the seizures, although oral vitamin B6, valproic acid, clonazepam, and zonisamide had little effect. Oral high-dose phenobarbital therapy was begun at a dosage of 15 mg/kg/day, and the seizures markedly decreased to 5-10 times per day and the epileptic discharges on electroencephalogram greatly decreased. Serum phenobarbital levels ranged between 60 and 100 mg/dL. High-dose phenobarbital therapy should be considered for the treatment of early infantile epileptic encephalopathy with suppression bursts.