Angelman syndrome in three adult patients with atypical presentation and severe neurological complications

Angelman syndrome (AS) is a distinct neurogenetic disorder and the phenotyp e is well known in childhood and adolescence. However, with advancing age t he clinical and behavioral phenotype changes. In adulthood, the phenotype c an be rather aspecific. We report on AS in 3 severely to profoundly mentall y retarded patients, who developed severe neurologic complications of sever e tremor, spasticity and coordination problems, resulting into severe loss of function. They presented atypical craniofacial Features, short stature, epileptic seizures, microcephaly, brachytelephalangy and absent speech. Two patients presented at an older age a change in day-night rhythm. Based on this experience, we conclude that all severely to profoundly mentally retar ded patients with atypical phenotype, spasticity, absent speech, epileptic seizures and changed day-night rhythm are candidates for further cytogeneti c and molecular investigation for AS. Clinical photographs of the patient a t a younger age can be helpful. The presence of the typical EEG pattern wit h frontal triphasic delta waves may direct to the diagnosis of AS.