ESPE Abstracts

Background: Prader–Willi syndrome (PWS) is characterised by neonatal hypotonia, hypogonadism, progressive obesity, short stature, and mental retardation. This syndrome arises from a loss of expression of paternally derived genes on chromosome 15q11–13 region.

Objective and hypotheses: The aim of this study was to investigate clinical characteristics and their genotypes in Korean patients with PWS.

Method: The study included 46 PWS patients diagnosed by clinical features and methylation test. And genetic subtypes were distinguished by using fluorescence in situ hybridisation (FISH). Birth history, auxological profile, clinical features, neurodevelopmental state, radiologic findings, and medication were reviewed, retrospectively. And BMI was analysed in patients more than 2 years old age.

Results: Total 46 PWS patients, 27 patients were male and 19 patients were female. Their age at diagnosis was 1.8±3.7 years. 39 patients (84.8%) were diagnosed within 1 year of age due to hypotonia and feeding difficulty, but other seven patients were diagnosed at 3–15 years old. FISH was performed in 39 patients and 29 paternal deletions (73.7%) and ten maternal UPDs (26.3%) were noted. 21 males (77.8%) undergone orchiopexy. 36 patients (78.3%) had received recombinant human GH therapy, and the mean age at the start of GH and duration of therapy were 2.7±2.9 and 3.3±2.4 years. 19 patients were obese (2.34±0.86, 19/37, 51.4%) and among them, GH group was less obese than non-GH group (41.9%, 100%, P<0.05). In GH group, early start group, who received GH from one year of age, were less obese than later starte group (7.7% vs 66.7% P<0.05). 20 patients (43.5%) had scoliosis. One patient had hip dysplasia, and one patient had pes planus. Six patients received anti-epileptic drugs for epilepsy, and all of them were paternal deletion. Two patients performed tonsillectomy due to sleep apnoea.

Conclusion: Our study showed that deletion was common, and early GH therapy improved BMI of Korean PWS patients. As PWS is a multi-systemic disorder, and there are different manifestations according to time, persistent and systemic monitoring should be needed.