Clinical analysis of childhood occipital lobe epilepsy in 43 Taiwanese patients.

Occipital lobe epilepsy in children can present as an idiopathic form (i.e., childhood epilepsy with occipital paroxysms) or as a symptomatic form. Forty-three children (18 boys, 25 girls) were divided into the idiopathic group or symptomatic group, according to the classification for epileptic seizures of the International League Against Epilepsy. Patients in the idiopathic group were further subdivided into the Panayiotopoulos or Gastaut type, according to clinical presentation. The idiopathic group consisted of 15 children (5 boys, 10 girls), of whom 11 were of the Panayiotopoulos type and 4 of the Gastaut type. The symptomatic group consisted of 28 children (13 boys, 15 girls). The average age of seizure onset in the idiopathic group was younger than in the symptomatic group (6.5 +/- 2.4 vs 8.5 +/- 3.0 years). Ictal vomiting was more common in the idiopathic group, and positive visual symptoms were more common in the symptomatic group. Mean epilepsy duration in the idiopathic group was shorter (5.7 +/- 5.3 vs 20.1 +/- 16.0 months), and the response to treatment was better. The average age of seizure onset was much younger in the Panayiotopoulos than in the Gastaut type (5.4 +/- 1.5 vs 9.5 +/- 1.5 years), and mean epilepsy duration was also shorter (3.9 +/- 4.2 vs 10.5 +/- 4.9 months). Seizure semiology can distinguish between idiopathic occipital lobe epilepsy and the symptomatic form with ictal vomiting and positive visual symptoms. In idiopathic occipital lobe epilepsy, the Panayiotopoulos type has better prognosis than the Gastaut type.

Multiple sclerosis with childhood onset: report of 21 cases in Taiwan.

Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system. However, the clinical features of childhood-onset multiple sclerosis in Asia have been rarely reported. This report presents our experience in 21 patients with multiple sclerosis (15 females, 6 males, mean age 12.4 +/- 4.5 years) in Taiwan with the onset age before 18. The most common presenting symptoms were limb weakness (62%) and visual disturbance (43%). Poly-symptomatic presentations were found in 16 (76%) patients. Magnetic resonance imaging demonstrated basal ganglion involvement in 33.3% of the patients. Neuroimaging and neurophysiologic evaluations revealed optic nerve involvement in 13 (62%) patients. Only one child had the optico-spinal form. Eighteen (86%) patients had a relapsing remission course, whereas three (14%) patients had secondary progressive course. Three (14%) patients initially diagnosed with acute disseminated encephalomyelitis developed multiple sclerosis after 4 months, 2 years, and 6 years, respectively. In conclusion, childhood multiple sclerosis in Taiwan is frequently poly-symptomatic, and is characterized by a higher ratio of optic nerve and basal ganglion involvement. However, the optico-spinal form of multiple sclerosis occurs rarely in children in Taiwan. Our experience suggests that the chance of relapsing should not be overlooked in patients presenting with clinical and neuroimaging findings suggestive of acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis in children: one medical center experience.

Acute disseminated encephalomyelitis (ADEM) is a rare inflammatory demyelinating disease of the central nervous system. The experience in children is limited. We retrospectively reviewed our experience with 20 ADEM patients (10 females, 10 males) with age of onset before 18 years old in Taiwan to clarify the clinical manifestations, neuroimaging findings, and the relationship between ADEM and multiple sclerosis (MS). The age at onset ranged from 4 months to 15 years. Seventeen (85%) children had a recent infectious prodrome. Children presented most often with acute consciousness disturbance (70%) and motor deficits (55%). Seizures occurred in 10 (50%), but only one child developed epilepsy in follow-up. Brain magnetic resonance imaging (MRI) evaluations done in all patients revealed multifocal lesions, mainly in subcortical white matter (80%), brainstem (65%), basal ganglia (55%), cerebellum (45%), thalamus (40%), and periventricular white matter (35%). Spinal cord MRI was performed in 9 patients and all of them showed abnormal lesions. Eleven patients were treated with high-dose intravenous methylprednisolone pulse therapy, and only one had mild long-term neurological sequelae. Among the 20 patients, five had long-term neurological sequelae and one died. Three patients fit the criteria of multiphasic disseminated encephalomyelitis, in which two developed MS in follow-up. Another patient with ADEM turned out to be MS two years later. We concluded that seizures are not uncommon in ADEM, but the subsequent development of epilepsy is rare. Long-term prognosis of ADEM is generally good. Because recurrence of ADEM is not uncommon, long-term follow-up of those children with ADEM is needed to distinguish between ADEM and MS.

ACTH therapy for Taiwanese children with West syndrome -- efficacy and impact on long-term prognosis.

To study the efficacy of adrenocorticotrophic hormone (ACTH) in treating Taiwanese children with West syndrome (WS) and the impact on long-term prognosis, 66 patients with WS (54 symptomatic and 12 cryptogenic) were collected from 1987 to 1998 in a medical center in Taiwan. A total of 53 patients were enrolled in this study and treated with ACTH at the dosage of 2.5IU/kg daily for 2 weeks with gradual tapering in subsequent 6 weeks. Immediate responses, side effects of ACTH and long-term outcomes of the patients including seizure and developmental status were evaluated during the average follow-up period of 35.6 months. The spasm-free percentage after one or two courses of ACTH treatment was 77.4%. Nine (17%) patients encountered severe side effects such as major infections, which prompted us to stop ACTH. At the end of follow-up, 22 (41.5%) patients had intractable seizures but 25 (47.2%) patients remained seizure free with or without anticonvulsants. The ACTH-responders had a better chance of remaining seizure free (P<0.05). Regarding the long-term developmental outcome, 12 (22.6%) patients had normal or borderline development; two thirds of them belonged to the crytpogenic group. Six (11.3%) patients expired and 24 (45.3%) were severely retarded; all but one of them belonged to the symptomatic group. The prognosis of WS heavily relies on whether a patient is cryptogenic or symptomatic (P<0.001). Good response to therapy or short treatment lag did not favorably affect the developmental outcomes of the symptomatic cases. We conclude that the long-term outcomes of WS in Taiwan were generally poor despite of treatment. Only cryptogenic patients had favorable prognosis. For symptomatic patients, ACTH therapy may be used to control the spasms and decrease the incidence of subsequent epilepsy, but it will not improve developmental outcome. Considering a high percentage of severe side effects in our study, a lower dosage of ACTH with adequate therapeutic efficacy but less side effects should be considered for treating Taiwanese children with WS.

The roles of electroencephalography and neuroimaging in children with holoprosencephaly.

We analyze the respective roles of neuro-imaging and EEG in the assessment of 11 children with holoprosencephaly and epilepsy. Seizures were present in seven patients (64%); six were treated with antiepileptic drugs; five had intractable epilepsy. Two of the patients with intractable epilepsy became seizure-free under polytherapy. Fourteen EEG recordings were performed in eight patients. The abnormal EEG findings included slow waves, focal epileptiform discharges, slow spike-and-wave complexes, hypsarrhythmia, frontal fast activity, fronto-occipital gradients of amplitudes (posterior amplitude attenuation), lack of photic driving, periodic discharges, and extremely large amplitudes. A fronto-occipital gradient was found only in alobar and semilobar holoprosencephaly (HPE), while hypsarrhythmia only in lobar HPE. Lack of photic driving was found only in alobar HPE. All EEGs showed diffuse slow waves, and all patients had severe developmental delay. The Deep Gray Score(DGS) in neuroimaging studies, thought to predict clinical outcome, was irrelevant given the presence and intractability of the epilepsies. Patients with higher DGS, nonetheless, tended to have higher mortality rate. In conclusion, EEG evaluation provides additional functional information to neuroimaging studies in the assessment of neurological outcome in patients with HPE. With a more mature and well-formed cerebrum, as found in the lobar and semilobar types, the possibility of hypsarrhythmia and photic driving increased, while that of fronto-occipital gradients decreased.

Adrenoleukodystrophy: clinical analysis of 9 Taiwanese children.

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder and identified in many races without apparent predilection for any race. This study was designed to investigate the clinical and therapeutic aspects of X-ALD in Taiwanese children with this disorder. We retrospectively reviewed all children admitted to NTUH from Nov. 1993 to Aug. 2002 with the diagnosis of ALD, defined by increased very long chain fatty acid (VLCFA). The mean age at diagnosis of the patients was 7.4 years (range, 2.8 to 13 years). Seven out of 9 patients had abnormal brain magnetic resonance image (MRI) studies. Three patients received bone marrow transplantation. Of these, two died of severe graft-versus-host disease and the other remained stable. Of the remaining 6 patients, two patients were in vegetative status and the other two patients were neurologically normal. X-ALD in Taiwanese children had similar clinical manifestations as reviewed in western countries. Symmetrical demyelination in parieto-occipital region and the accumulation of contrast material at the edge of the lesion are the typical MRI findings. Proton MR spectroscopy (MRS) can be used to evaluate either the asymptomatic patient or patient with normal brain image. Performance of T-cell depletion bone marrow transplantation or cord blood transplantation is suggested for X-ALD with early cerebral involvement.

Cerebral infarction associated with possible enteroviral infection in an infant.

Enterovirus infection has been rarely reported to cause cerebral infarction in infants. We describe a 2-month-old boy with right focal seizure and right hemiparesis associated with enterovirus infection during an epidemic of enterovirus 71 infection in Taiwan in 1998. Magnetic resonance imaging and angiography showed vasculitis in the left anterior cerebral artery with cerebral infarction. In the unclarified pathogenesis of cerebral disease in enterovirus infection, this case suggests focal vasculitis with subsequent cerebral infarction. Enterovirus-related vasculitis of the central nervous system is thus another consideration when facing a child with focal seizure, acute hemiplegia and cerebral infarction.

Anti-epileptic drugs-induced de novo absence seizures.

The authors present three patients with de novo absence epilepsy after administration of carbamazepine and vigabatrin. Despite the underlying diseases, the prognosis for drug-induced de novo absence seizure is good because it subsides rapidly after discontinuing the use of the offending drugs. The gamma-aminobutyric acid-transmitted thalamocortical circuitry accounts for a major part of the underlying neurophysiology of the absence epilepsy. Because drug-induced de novo absence seizure is rare, pro-absence drugs can only be considered a promoting factor. The underlying epileptogenecity of the patients or the synergistic effects of the accompanying drugs is required to trigger the de novo absence seizure. The possibility of drug-induced aggravation should be considered whenever an unexpected increase in seizure frequency and/or new seizure types appear following a change in drug treatment. By understanding the underlying mechanism of absence epilepsy, we can avoid the inappropriate use of anticonvulsants in children with epilepsy and prevent drug-induced absence seizures.

Agyria-pachygyria: clinical, neuroimaging, and neurophysiologic correlations.

Agyria-pachygyria complex is a disorder of neuronal migration and organization. Patients suffer either motor or intellectual retardation. We report our experiences of 10 patients with agyria-pachygyria complex and evaluate their clinical features, electroencephalography, and evoked potentials. Of nine electroencephalography examinations, five patients demonstrated characteristically high-amplitude fast activity. One of nine patients had an abnormal brainstem auditory-evoked potential. Three of seven patients had abnormal goggled visual-evoked potential. Six patients received somatosensory-evoked potential examinations, and five of these were abnormal, including four with prolonged central conduction times. Of the 10 patients, eight survived with variable intellectual and motor retardation; two died of sepsis. Patients with grades 1-4 agyria-pachygyria had high incidences of somatosensory-evoked potential abnormalities and also suffered worse neurologic outcomes. Normal brainstem auditory-evoked potential but abnormal cortical somatosensory-evoked potential components and prolonged central conduction time in these patients indicate that agyria-pachygyria is a supratentorial disease. We conclude that somatosensory-evoked potential examination is supplemental to neuroimaging in predicting the neurologic prognosis of patients with agyria-pachygyria.

Schizencephaly: correlation between clinical and neuroimaging features.

Schizencephaly is an uncommon congenital brain malformation. We report our experience of 13 patients with schizencephaly and evaluate the clinical, neuroradiologic, electroencephalographic (EEG), and nosological features. Of these 13 patients, 8 were unilateral forms, 5 were bilateral forrms and 11 were open-lip type schizencephaly. One patient was proven to have cytomegalovirus (CMV) infection. The clinicalfeatures and neurodevelopmental outcomes are variable. Although seizure developed in 9 patients (5 patients from unilateral and 4 from bilateral forms), the severity of epilepsy was not totally related to the degree of malformations. The neurodevelopmental outcome depended on the extent of schizencephaly as well as the seizure control. Those with bilateral forms and intractable seizures had the worst outcome. Other central nervous system (CNS) anomalies were observed in 11 patients. Six out of 11 patients had focal cortical dysplasia. We conclude that children with schizencephaly usually have variable neurological impairment. Earlier diagnosis of schizencephaly and related CNS malformation with neuroimaging is helpful in predicting the neurodevelopmental outcomes in these patients.

Concentration-dependent disposition of glucuronide metabolite of valproate.

The glucuronide conjugation metabolism of valproate (VPA) has been assessed to be non-linear within the therapeutic concentration range. However, disposition of its metabolite, valproic acid glucuronide (VPAG), in relation to VPA doses is unclear. The purpose of this study was to elucidate the characteristics of dose-related disposition of VPAG. Guinea-pigs were treated with an intravenous bolus dose of sodium valproate at 20, 100, 500 or 600 mg kg(-1). Plasma was sampled on a pre-selected time schedule, and bile and urine were collected. Concentrations of VPA and VPAG in plasma, bile and urine were determined by gas chromatography. The pharmacokinetics of VPA and VPAG both were dose-dependent. However, the plasma concentration-time profiles of VPAG and VPA were not parallel. At a usual dose of VPA (20 mg kg(-1)), plasma VPAG declined with plasma VPA, whereas at a high dose of VPA (>500mg kg(-1)), plasma VPAG was elevated against the decline of plasma VPA, which suggested accumulation of plasma VPAG possibly owing to saturated elimination. The biliary and urinary clearances of VPA (vCLb and vCLu) were independent of dose. However, the clearances of plasma VPA (vCLp), plasma VPAG (gCLp), biliary and urinary VPAG (gCLb and gCLu) all were decreased against the increase in VPA doses. The dose-dependent decrease of gCLu (from 3.19 to 1.12 mL min(-1)) was less pronounced than that of gCLp (from 6.72 to 0.86 mL min(-1)) and the gCLu turned to exceed the gCLp at high doses of VPA (> 500 mg kg(-1)). These results suggest that the excess urinary VPAG might be produced in kidney. In conclusion, at a high dose of VPA, plasma VPAG is accumulated. The concentration-dependent biliary and urinary recovery of VPAG might be governed by a saturable elimination process rather than by saturable hepatic biotransformation rate. Glucuronide conjugation metabolism of VPA in kidney is speculated, which might be minor at low levels of plasma VPA, but more obvious after saturation of hepatic glucuronidation.

Postmeningoencephalitic dysautonomia: report of one case.

We present a patient with postinfectious dysautonomia, which developed 2 weeks after a meningoencephalitic episode. The chief dysautonomic symptoms and signs included constipation, urinary dysfunction, anhydrosis, ptosis, and orthostatic hypotension. Neurophysiologic studies revealed no involvement of the somatic nervous system. The dysautonomia recovered gradually 3 months later with minimal supportive treatment.