Abstract

The aim of the paper was to provide a short overview of Angelman (AS) and Prader-Willi syndromes (PWS) and to introduce a clinical study performed on patients with AS and PWS in Estonia.
Aim of the study. The purpose of our study was to describe the clinical phenotype of patients with AS and PWS, aiming to ascertain the symptoms facilitating early recognition of both syndromes and the health problems posing a potential vital risk.
Methods. The study subjects were children with a positive DNA methylation test for AS and PWS. All children underwent investigations at the Children’s Clinic of the University of Tartu. Each patient with suspected AS had EEG, and each patient with suspected PWS had ENMG. In all cases ECG, CT or MRI, a carpogram and abdominal ultrasound were performed. All children were also examined by a team (child neurologist, psychologist, physiotherapist, otorhinolaryngologist and ophthalmologist).
Results. We found that testing for AS in the first year  of life is indicated when a combination of the following symptoms are present: irritability, sleep disturbances, feeding difficulties, developmental delay with slow progression in head growth, truncal hypotonia with pyramidal signs, specific EEG pattern and/or seizures. PWS is characterized by a coexistence of profound central muscular hypotonia, insufficient arousal, no interest in food, transient bradycardia and thermolability, peculiar skin appearance, characteristic facial phenotype, and peculiar position of the thumbs in a term neonate.
The childhood clinical phenotype of the syndromes was generally similar to that of previously described patients; the exceptions were frequent brain abnormalities and cardiac problems in patients with PWS and abnormal bone maturation in the case of both syndromes.
Conclusions. To improve the quality of life of persons with AS and PWS, early diagnosis and syndrome-specific clinical management are essential.