Further characterization of CAPOS/CAOS syndrome with the Glu818Lys mutation in the ATP1A3 gene: A case report.

A 38-year-old female patient experienced recurrent episodes of neurological deterioration during febrile illness at the age of 7 and 8 months, and 2, 4, and 37 years. Acute symptoms comprised unconsciousness, headache, abnormal ocular movements, flaccid paralysis with areflexia, ataxia, dysphagia, and movement disorders. Each episode of neurological deterioration was followed by partial recovery with residual symptoms of progressive disturbance of visual acuity with optic atrophy and hearing loss, moderate intellectual disability, strabismus, ophthalmoplegia, as well as fluctuating degree of gait ataxia, chorea, tremor, and myoclonus. In addition, electrocardiography revealed incomplete right bundle branch block. The genetic testing revealed a de novo heterozygous mutation of c.2452G > A (p.Glu818Lys) in the ATP1A3 gene, which was compatible with the clinical phenotype of CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss)/CAOS syndrome. Here we discuss the significance of clinical features of a patient, overlapping with those of alternating hemiplegia of childhood, along with a literature review.

Pharmacoresistant epileptic eyelid twitching in a child with a mutation in SYNGAP1.

SYNGAP1 gene mutation has been associated with epilepsy which is often drug resistant, with seizure types including eyelid myoclonia. However, detailed descriptions, including ictal video-EEG, have not been reported. We report the case of a 4-year-old boy who developed recurrent epileptic eyelid twitching at 1 year and 5 months of age. Seizures gradually increased in frequency to more than 50 times per day and manifested with upward eye deviation, motion arrest, loss of consciousness, and eyelid twitching lasting for five seconds. Ictal EEG showed rhythmic, generalized slow or spike-and-wave complex activity with posterior predominance. Moderate psychomotor developmental delay and unsteady gait were also noted. Neuroimaging results were normal. Seizures were refractory to carbamazepine and levetiracetam but were reduced in frequency by ethosuximide and lamotrigine administration. Genetic analysis identified a c.3583-6 G>A mutation in the SYNGAP1 gene. SYNGAP1 gene analysis should be considered for intellectually disabled patients with early-onset drug resistant eyelid twitching and photosensitivity. Further clinical research on SYNGAP1 function may be necessary to treat epilepsy of this aetiology. [Published with video sequence on www.epilepticdisorders.com].

Behavioral and psychiatric disorders in Prader-Willi syndrome: a population study in Japan.

Prader-Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder characterized by mental retardation and distinct physical, behavioral, and psychiatric features. Based on parents' questionnaires, we examined the prevalence of behavioral and psychiatric disorders of 165 persons with PWS aged 2-31 years in Japan. The data were analyzed comparing four different age groups with PWS: group 1, 2-5 years (n=34); group 2, 6-11 years (n=57); group 3, 12-17 years (n=45); and group 4, 18-31 years (n=29). Further, we compared the results of our PWS group 4 with those of 42 age-, gender-, and intelligence level-matched intellectual disability (ID) individuals without PWS. Our results showed that repetitive speech and stubbornness were prominent from early childhood and other behavioral problems such as hyperphagia, stealing food, temper tantrums, lying, and emotional lability tended to be more frequent with age among persons with PWS. Moreover, young adults with PWS have significantly higher rates of behavioral and psychiatric disorders than IDs without PWS, such as stubbornness, hyperphagia, temper tantrums, self-injurious behavior (skin picking), hypersomnia, inactivity, and delusion. Degree of obesity was not necessarily related to behavioral and psychiatric features associated with PWS. Our findings revealed that persons with PWS are more vulnerable to behavioral and psychiatric disorders particularly in young adulthood compared to those with ID from other etiologies in Japan.

Disappearance of frontal N30 component of median nerve stimulated SSEPs in two young children with abnormal striatal lesions.

Median nerve stimulated short-latency somatosensory evoked potentials (MN-SSEPs) were performed in two young children with extrapyramidal symptoms. Brain MRI showed bilaterally symmetric striatal lesions in both cases. The subcortical components (N9, N11, N13, N18, P11, and P13) and the parietal component (N20) were normally detected, whereas the frontal component (N30) was not detected bilaterally in either case. In conclusion, our findings suggest that frontal N30 disappearance could be observed since as early as young childhood and it may pathophysiologically reflect severe dysfunction in the extrapyramidal system.