Natural history of KBG syndrome in a large European cohort.

KBG syndrome (KBGS) is characterized by distinctive facial gestalt, short stature and variable clinical findings. With ageing, some features become more recognizable, allowing a differential diagnosis. We aimed to better characterize natural history of KBGS. In the context of a European collaborative study, we collected the largest cohort of KBGS patients (49). A combined array- based Comparative Genomic Hybridization and next generation sequencing (NGS) approach investigated both genomic Copy Number Variants and SNVs. Intellectual disability (ID) (82%) ranged from mild to moderate with severe ID identified in two patients. Epilepsy was present in 26.5%. Short stature was consistent over time, while occipitofrontal circumference (median value: -0.88 SD at birth) normalized over years. Cerebral anomalies, were identified in 56% of patients and thus represented the second most relevant clinical feature reinforcing clinical suspicion in the paediatric age when short stature and vertebral/dental anomalies are vague. Macrodontia, oligodontia and dental agenesis (53%) were almost as frequent as skeletal anomalies, such as brachydactyly, short fifth finger, fifth finger clinodactyly, pectus excavatum/carinatum, delayed bone age. In 28.5% of individuals, prenatal ultrasound anomalies were reported. Except for three splicing variants, leading to a premature termination, variants were almost all frameshift. Our results, broadening the spectrum of KBGS phenotype progression, provide useful tools to facilitate differential diagnosis and improve clinical management. We suggest to consider a wider range of dental anomalies before excluding diagnosis and to perform a careful odontoiatric/ear-nose-throat (ENT) evaluation in order to look for even submucosal palate cleft given the high percentage of palate abnormalities. NGS approaches, following evidence of antenatal ultrasound anomalies, should include ANKRD11.

Language-induced epilepsy, acquired stuttering, and idiopathic generalized epilepsy: phenotypic study of one family.

PURPOSE: Language-induced epilepsy involves seizure precipitation by speaking, reading, and writing. Seizures are similar to those of reading epilepsy (RE). The nosologic position of language-induced epilepsy is not clear. We performed a clinical and neurophysiological study in a multigenerational family with the association of idiopathic generalized epilepsy (IGE) with ictal stuttering as a manifestation of reflex language-induced epilepsy. METHODS: Nine members on three generations were studied. All patients underwent video-polygraphic EEG recordings (awake and during sleep). A standardized protocol was applied to test the effect of language and non-language-related tasks. RESULTS: Six patients presented language-induced jaw jerking that mimicked stuttering and corresponded to focal myoclonus involving facial muscles. This was associated with an IGE phenotype in four of these patients. Focal EEG spikes were found in all six patients by visual analysis and/or back-averaging techniques. The focal spikes were either asymptomatic (when followed by a slow wave) or symptomatic of facial myoclonia (when isolated). Levetiracetam, used as add-on or monotherapy in four patients, suppressed ictal stuttering. One additional case only had a phenotype of IGE without focal features. CONCLUSIONS: This family study demonstrates the phenotypic heterogeneity of the association of IGE phenotype with ictal stuttering (language-related reflex seizure). Our data suggest that this particular form of reflex epilepsy related to language has more similarities with generalized epilepsies than with focal ones. Neurophysiological investigations should be performed more systematically in patients with acquired stuttering, especially if there is family history of IGE.