Predictors of developmental dyslexia in European orthographies with varying complexity.

BACKGROUND: The relationship between phoneme awareness, rapid automatized naming (RAN), verbal short-term/working memory (ST/WM) and diagnostic category is investigated in control and dyslexic children, and the extent to which this depends on orthographic complexity. METHODS: General cognitive, phonological and literacy skills were tested in 1,138 control and 1,114 dyslexic children speaking six different languages spanning a large range of orthographic complexity (Finnish, Hungarian, German, Dutch, French, English). RESULTS: Phoneme deletion and RAN were strong concurrent predictors of developmental dyslexia, while verbal ST/WM and general verbal abilities played a comparatively minor role. In logistic regression models, more participants were classified correctly when orthography was more complex. The impact of phoneme deletion and RAN-digits was stronger in complex than in less complex orthographies. CONCLUSIONS: Findings are largely consistent with the literature on predictors of dyslexia and literacy skills, while uniquely demonstrating how orthographic complexity exacerbates some symptoms of dyslexia.

Specific language impairment versus Landau-Kleffner syndrome.

The occurrence of sleep electroencephalography (EEG) abnormalities in some children with specific language impairment (SLI), the various forms of language dysfunction patterns seen in children with benign childhood epilepsy with centrotemporal spikes (BECTS), and finally the acquired aphasia in Landau-Kleffner syndrome (LKS) indicate a large spectrum of interactions between language and epilepsy. As such, the question is whether SLI and LKS should rather be considered along a continuum or as two entirely distinct entities. In addition, the rationale for using antiepileptic medications in rare forms of SLI is discussed.

The ketogenic diet improves recently worsened focal epilepsy.

AIM: We observed a dramatic response to the ketogenic diet in several patients with highly refractory epilepsy whose seizure frequency had recently worsened. This study aimed to identify whether this characteristic was a useful indication for the ketogenic diet. METHOD: From the 70 patients who received the ketogenic diet during a 3-year period at our institution, we retrospectively selected patients with focal epilepsy. There were 22 children, 13 females and nine males, aged from 5 months to 18 years 6 months (mean 6y 9mo, SD 5y 11mo). Fifteen had symptomatic and seven had cryptogenic focal epilepsy. Seizure frequency 1 week before initiating the ketogenic diet was compared with that at 1 month and at the last visit on the diet. RESULTS: Eleven patients were responders (defined as reduction of seizures by more than 50%) at 1 month. Responders were higher (p=0.046) in the group with a recent worsening of seizures than in those with stable seizure frequency. Seven patients were still seizure-free at 6 months on the diet. Tolerability was excellent in 10 patients. Five patients stopped the diet because of early side effects. INTERPRETATION: The ketogenic diet may be a valuable therapeutic option for children with pharmacoresistant focal epilepsy, particularly those with a recent deterioration of seizure control and neurological status. Because of its rapid effect, the ketogenic diet may be a useful support to intravenous emergency drugs in such a situation.

Cognitive functions in children with benign childhood epilepsy with centrotemporal spikes (BECTS).

Benign childhood epilepsy with centrotemporal spikes (BECTS) is regarded as a benign form of epilepsy because of its usually favorable outcome, in terms of seizures. Eighteen children with BECTS were studied in terms of neuropsychological and learning abilities: intellectual quotient, oral language (phonological production, naming skills, verbal fluency and syntactic comprehension), drawing and visuo-spatial skills, visual and selective attention, verbal and visuo-spatial memory, reading, numeracy and spelling. The mean IQ of the population was within the normal range, but individual results were heterogeneous. Verbal functions and memory were normal. In contrast, drawing and visuo-spatial skills, attention and visuo-spatial memory were significantly weak compared to the normal range for age. Reading, numeracy and/or spelling ability were significantly delayed by one academic year or more in ten of the children. In conclusion, despite its benign outcome in terms of epilepsy, BECTS can be accompanied by specific cognitive disorders and low academic achievement.

Exclusion of the dymeclin and PAPSS2 genes in a novel form of spondyloepimetaphyseal dysplasia and mental retardation.

Spondyloepimetaphyseal dysplasias (SEMD) represent a heterogeneous group of conditions composed of at least 15 well-defined entities. The classification is based on clinical, radiological and molecular findings. Among them, several conditions also include a mental retardation (MR) syndrome, namely Wolcott-Rallison syndrome, Dyggve-Melchior-Clausen syndrome (DMC) and lysosomal storage disorders. Here, we report on a novel form of SEMD with MR in two Pakistani sisters born to first-cousin parents. SEMD, MR, microcephaly, ataxia, facial dysmorphism and hirsutism of back and legs were noted in the two children. Skeletal findings included flat vertebral bodies with irregular vertebral plates, irregular and flared metaphyses with vertical striations, small and irregular epiphyses, small carpal bones and narrow iliac wings without lacy pelvis iliac crest. Similarities with DMC prompted us to test and eventually exclude the DMC gene, dymeclin, by direct sequencing. Similarly, we excluded the PAPSS2 gene (3'-alpha phosphoadenosine 5'-phosphosulphate synthase 2) responsible for SEMD Pakistani type. The combination of features observed in the two sisters does not fit with any previously reported SEMD and represents therefore a novel form of autosomal recessive SEMD with MR.

The nonmalformed hemisphere is secondarily impaired in young children with hemimegalencephaly: a pre- and postsurgery study with SPECT and EEG.

PURPOSE: To study separately the functional value of each cerebral hemisphere in hemimegalencephaly (HME). HME is a unique model of unilateral hemispheric lesion, but one suspects that the non-HME hemisphere also could be functionally impaired because the postsurgery outcome is less favorable than expected. METHODS: We performed simultaneous prolonged EEG and 133-xenon SPECT (single-photon emission computed tomography); we measured the absolute values of cerebral blood flow (CBF) in both hemispheres and compared them with the normal values previously acquired. Thirteen patients (aged 5-38 months) underwent 31 examinations, 20 before surgery (hemispherotomy) and 11 after. RESULTS: In the HME hemisphere, we confirmed the presurgical mixture of increased and decreased CBF due to intermittent ictal discharges. After surgery, CBF was decreased in most cases. In the non-HME hemisphere, presurgery CBF was abnormal in 60% of the patients, increased and related mostly to diffuse interictal spikes on the same side, whereas normal CBF cases had focal spikes. After surgery, CBF was normal in 82% of cases, corresponding to an EEG without diffuse spikes. In the six patients longitudinally studied, CBF dramatically decreased after surgery in the HME hemisphere, whereas in the non-HME hemisphere, CBF was mostly normal very early (three fourths before 2 months), increased as soon as 3 months, and normalized only after hemispherotomy, the more rapidly the child was operated on, the earlier it was. CONCLUSIONS: This study shows that the function of the nonmalformed hemisphere is impaired as soon as the first months of the course of HME but can be restored after surgery. Our data support the recommendations to operate on the children as early as possible.