A survey of seizures and current treatments in 15q duplication syndrome.

OBJECTIVE: Seizures are common in individuals with duplications of chromosome 15q11.2-q13 (Dup15q). The goal of this study was to examine the phenotypes and treatments of seizures in Dup15q in a large population. METHODS: A detailed electronic survey was conducted through the Dup15q Alliance containing comprehensive questions regarding seizures and their treatments in Dup15q. RESULTS: There were 95 responses from Dup15q families. For the 83 with idic(15), 63% were reported to have seizures, of which 81% had multiple seizure types and 42% had infantile spasms. Other common seizure types were tonic-clonic, atonic, myoclonic, and focal. Only 3 of 12 individuals with int dup(15) had seizures. Broad spectrum antiepileptic drugs (AEDs) were the most effective medications, but carbamazepine and oxcarbazepine were also effective, although typical benzodiazepines were relatively ineffective. There was a 24% response rate (>90% seizure reduction) to the first AED tried. For those with infantile spasms, adrenocorticotropic hormone (ACTH) was more effective than vigabatrin. SIGNIFICANCE: This is the largest study assessing seizures in Duplication 15q syndrome, but because this was a questionnaire-based study with a low return rate, it is susceptible to bias. Seizures are common in idic(15) and typically difficult to control, often presenting with infantile spasms and progressing to a Lennox-Gastaut-type syndrome. Seizures in those with int dup(15) are less common, with a frequency similar to the general autism population. In addition to broad spectrum AED, medications such as carbamazepine and oxcarbazepine are also relatively effective in controlling seizures in this population, suggesting a possible multifocal etiology, which may also explain the high rate of infantile spasms. Our small sample suggests a relative lack of efficacy of vigabatrin and other γ-aminobutyric acid (GABA)ergic medications, such as typical benzodiazepines, which may be attributable to abnormal GABAergic transmission resulting from the duplication of a cluster of GABAß3 receptor genes in the 15q11.2-13 region.

Cardiac fat-containing lesions are common in tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is a highly variable, multisystem, genetic disorder that affects approximately 1:6,000 individuals. It has previously been thought that the cardiac manifestation of TSC is congenital rhabdomyomas, which occur during infancy and typically regress during childhood. Recently, there have been findings of cardiac fat-containing lesions in adult TSC patients that appear distinct from the presence of cardiac rhabdomyomas. We review the chest CT scans of 73 individuals with TSC to check for cardiac fat-containing lesions. Fat-containing lesions were found in the heart of approximately one-third of adolescents and adults with TSC. In this population with cardiac fat-containing lesions, no statistically significant difference was observed between the genders and between the different mutation types. Compared to those without cardiac fat findings, those with cardiac fat were more than twice as likely to have another abdominal manifestation of TSC. The results indicate that it may be appropriate to consider these cardiac fat foci as a clinical criterion for the diagnosis of TSC, given their frequency in our population. Our findings also suggest that a relation exists between the cardiac fat-containing lesions and other abdominal angiomyolipomas. More research regarding these cardiac fat-containing lesions is needed to better characterize their origin and clinical significance.