Williams syndrome:: Clinical, cytogenetic, neurophysiological and neuroanatomic features in 44 patients

Background. Williams syndrome (WS) is a genetically based disorder caused by deletion of elastin and contiguous genes on chromosome 7q11.23. This syndrome is characterized by multiorganic involvement with dysmorphic facial features and a distinctive cognitive profile. It is art interesting model for elucidation of relationships between brain, cognition and genes. Patients have a visual-spatial cognition impaired with relative strengths in social and language abilities. Aim: To report clinical, cytogenetic, neurophysiological and neuroanatomic features in 44 Patients referred as WS. Patients and methods: Forty four patients, aged 2 to 17 years, with the clinical diagnosis of Williams syndrome were studied with fluorescence in situ hybridization (FISH). In three cases, electrophysiological and neuroimaging studies were performed. Result. The deletion was confirmed in 23 patients. In three patients with neurophysiological studies, event related potentials suggested a cognitive difficulty in detecting and processing visual stimuli. Magnetic resonance imaging showed normal brain morphology. SPECT showed hypoperfusion of the right frontal lobe and bilateral anterior cingulum hyperperfusion. Conclusions: There are functional alterations in the brains of patients with Williams, which may be related to the cognitive deficits.