Long-term outcome in children with low grade tectal tumours and obstructive hydrocephalus.

BACKGROUND: Neuropsychological deficits after treatment of paediatric brain tumour are well known, but not the role of hydrocephalus in these deficits. AIMS: To study long-term neurological, cognitive, and behavioural deficits in children with a low grade tectal tumour and acquired obstructive hydrocephalus. METHODS: In a consecutive series of 12 children with low-grade tectal tumour diagnosed in our hospital between 1994 and 2008, neurologic, neuropsychological, and radiologic data were prospectively collected. Intelligence, memory, attention, language, visual-spatial, and executive functions were assessed. Median follow-up was 2 years and 9 months. RESULTS: At follow-up, most frequent neurologic disability was fatigue in children with a low-grade tectal tumour. They scored lower on sustained attention, long-term memory and had more behavioural problems. Factor influencing cognition was persisting severe hydrocephalus at time of assessment. The cognitive problems resulted in 60% of children needing assistances of special services at school. CONCLUSIONS: At long-term, children with a low-grade tectal tumour display invalidating neuropsychological impairments resulting in educational problems. Adequate treatment of hydrocephalus may result in better cognitive functioning. Our findings suggest that part of the symptoms of the cerebellar cognitive affective syndrome may not have resulted from a cerebellar lesion itself but rather from a cerebral dysfunction or compression of supratentorial structures in the cerebello-cortical circuitry due to the obstructive hydrocephalus.

The phenotype of the Gly94fsX222 PMP22 insertion.

Point mutations in PMP22 are relatively rare and the phenotype may vary from mild hereditary neuropathy with liability to pressure palsies (HNPP) to severe Charcot-Marie-Tooth type 1 (CMT1). We describe the phenotype of the Gly94fsX222 mutation in the PMP22 gene. Medical records of all patients were reviewed and 11 patients were re-examined. EMG was carried out in nine patients and nerve biopsy in one. Thirteen patients originating from seven families with a Gly94fsX222 mutation were included and consisted of 10 women and 3 men with a median age of 41 years (range 7-67). Five index patients were originally suspected of CMT1. Ten patients had abnormal motor skills during childhood. Nine patients had a history of pressure palsies. Involvement of the olfactory, trigeminal, facial, and pudendal nerves occurred in three patients. Twelve patients had pes cavus and one scoliosis. Distal anterior leg and distal arm weakness were found in 12 and 4 patients, respectively. Twelve patients had distal leg sensory abnormalities. Electrophysiological examination revealed a demyelinating sensorimotor neuropathy, both resembling CMT1 and HNPP. Sural nerve biopsy showed demyelinating neuropathy with presence of tomacula. More than three-fourths of the patients with Gly94fsX222 mutation demonstrated a CMT1 phenotype combined with transient deficits. Clinicians should test for this mutation in those patients exhibiting a generalised neuropathy combined with compressive like episodes.

Characterisation of TSC1 promoter deletions in tuberous sclerosis complex patients.

Tuberous sclerosis complex (TSC), an autosomal dominant disorder, is a multisystem disease with manifestations in the central nervous system, kidneys, skin and/or heart. Most TSC patients carry a pathogenic mutation in either TSC1 or TSC2. All types of mutations, including large rearrangements, nonsense, missense and frameshift mutations, have been identified in both genes, although large rearrangements in TSC1 are scarce. In this study, we describe the identification and characterisation of eight large rearrangements in TSC1 using multiplex ligation-dependent probe amplification (MLPA) in a cohort of 327 patients, in whom no pathogenic mutation was identified after sequence analysis of both TSC1 and TSC2 and MLPA analysis of TSC2. In four families, deletions only affecting the non-coding exon 1 were identified. In one case, loss of TSC1 mRNA expression from the affected allele indicated that exon 1 deletions are inactivating mutations. Although the number of TSC patients with large rearrangements of TSC1 is small, these patients tend to have a somewhat milder phenotype compared with the group of patients with small TSC1 mutations.

Paroxysmal disorders in infancy and their risk factors in a population-based cohort: the Generation R Study.

AIM: To examine the incidence of paroxysmal epileptic and non-epileptic disorders and the associated prenatal and perinatal factors that might predict them in the first year of life in a population-based cohort. METHOD: This study was embedded in the Generation R Study, a population-based prospective cohort study from early fetal life onwards. Information about the occurrence of paroxysmal events, defined as suddenly occurring episodes with an altered consciousness, altered behaviour, involuntary movements, altered muscle tone, and/or a changed breathing pattern, was collected by questionnaires at the ages of 2, 6, and 12 months. Information on possible prenatal and perinatal determinants was obtained by measurements and questionnaires during pregnancy and after birth. RESULTS: Information about paroxysmal events in the first year of life was available in 2860 participants (1410 males, 1450 females). We found an incidence of paroxysmal disorders of 8.9% (n=255) in the first year of life. Of these participants, 17 were diagnosed with febrile seizures and two with epilepsy. Non-epileptic events included physiological events, apnoeic spells, loss of consciousness by causes other than epileptic seizures or apnoeic spells, parasomnias, and other events. Preterm birth (p<0.001) and low Apgar score at 1 minute (p<0.05) were significantly associated with paroxysmal disorders in the first year of life. Continued maternal smoking during pregnancy and preterm birth were significantly associated with febrile seizures in the first year of life (p<0.05). INTERPRETATION: Paroxysmal disorders are frequent in infancy. They are associated with preterm birth and a low Apgar score. Epileptic seizures only form a minority of the paroxysmal events in infancy. In this study, children whose mothers continued smoking during pregnancy had a higher reported incidence of febrile seizures in the first year of life. These findings may generate various hypotheses for further investigations.

When to start drug treatment for childhood epilepsy: the clinical-epidemiological evidence.

INTRODUCTION: Many data on the course and prognosis after provoked and unprovoked single and multiple seizures in childhood have been collected in the past decennia by prospective, large-scale, long-term observational cohort studies. These data may serve to guide treatment decisions and help to design controlled trials investigating treatment strategies in childhood epilepsy. METHODS: The results of the Dutch study of epilepsy in childhood will be compared with those of other studies. We will also discuss the potential consequences of these results for the "why" and "when" of the decision to start treatment. RESULTS: Recurrence after a solitary unprovoked seizure in childhood is about 50%. Those with a recurrence have a similar outcome of their epilepsy compared to children presenting with multiple seizures, regardless whether they were treated after the first seizure or not. This argues in favour of postponing anti-epileptic drug (AED) treatment until at least a second seizure has occurred. After an unprovoked status epilepticus (SE), later outcome is not worse than after presentation with a short seizure. Therefore, long-term AED treatment after a single unprovoked SE may not be necessary either. The same holds true for children presenting with a short (less than one week) burst of unprovoked seizures. One quarter of them do not have recurrences and the final prognosis of children with recurrences does again not differ from the prognosis of the entire cohort. Findings in new-onset epilepsy further indicate that AED treatment can be safely omitted or at least postponed in about 15%, especially those with only a small number of seizures before presentation, those with benign partial epilepsy and those with sporadic generalised tonic-clonic seizures. On the reverse side, three considerations might lead to the decision to start early and aggressive treatment: the dangers of the seizures, the chance of intractability and the possibility of intellectual decline caused by recurrent seizures or epileptic activity. In idiopathic generalised absence epilepsy, the risks of accidents and learning problems indeed prompt early AED treatment. A self-propagating mechanism of seizures promoting the occurrence of more seizures, in the end causing intractable epilepsy (Gowers), occurs only rarely. Real intractability is seen in only 5-15% of the children with new-onset epilepsy. The chance of intractability is increased by variables like symptomatic aetiology, localisation-related epilepsy, and an early unfavourable course. Landau-Kleffner or continuous spikes and waves during sleep (CSWS) syndrome cause cognitive decline and syndromes like West, Lennox-Gastaut or Dravet's induce both psychomotor regression and intractability. In such cases, early aggressive treatment is indicated, including early consideration of the ketogenic diet, immunotherapy, vagus nerve stimulation and, if possible, referral for epilepsy surgery. CONCLUSIONS: Omitting or postponing treatment after a solitary seizure, an unprovoked SE, a single burst of seizures or multiple infrequent seizures usually does not worsen the prognosis. A poor prognosis and the consequent indication for early and aggressive treatment are dependent mainly upon the presence of variables like symptomatic aetiology, certain epilepsy types and syndromes, and the early evolution of the epilepsy in that particular child. Intellectual decline caused by seizures or epilepsy is rare and may be confined to certain specific and readily recognizable syndromes.

Impact of neurofibromatosis type 1 on school performance.

School functioning of 86 Dutch neurofibromatosis type 1 children (7-17 years) using teacher questionnaires was analyzed to determine the impact of neurofibromatosis type 1 on school performance. In all, 75% of the neurofibromatosis type 1 children performed more than 1 standard deviation below grade peers in at least one of the domains of spelling, mathematics, technical reading or comprehensive reading. Furthermore, neurofibromatosis type 1 children had a 4-fold increased risk for attending special education and a 6-fold increased risk for receiving remedial teaching for learning, behavior, speech, or motor problems. Children without apparent learning disabilities still frequently displayed neuropsychological deficits. Only 10% of the children did not show any school-functioning problems. Finally, it was found that the clinical severity of neurofibromatosis type 1 correlated with the cognitive deficits. Taken together, it was shown that neurofibromatosis type 1 has profound impact on school performance. Awareness of these problems may facilitate timely recognition and appropriate support.

Early onset neuropathy in a compound form of Charcot-Marie-Tooth disease.

A 2-year-old boy presented with early-onset Charcot-Marie-Tooth disease (CMT). His parents had not been diagnosed previously with CMT, but on careful examination they showed clinical signs of CMT and reduced nerve conduction velocities. Genetic analysis identified the boy as a heterozygote for both a peripheral myelin protein 22 (PMP22) duplication and a mutation in the lipopolysaccharide-induced-tumour-necrosis-factor-alpha-factor (LITAF) gene, whereas each parent only had one mutated CMT gene. This suggests that LITAF mutations can severely affect the CMT phenotype caused by a PMP22 duplication.