Clinical and molecular evaluation of 16 patients with Rett syndrome

Abstract

SUMMARY: Zengin-Akkuş P, Taşkıran EZ, Kabaçam S, Şimşek-Kiper PÖ,Haliloğlu G, Boduroğlu K, Utine GE. Clinical and molecular evaluation of 16patients with Rett syndrome. Turk J Pediatr 2018; 60: 1-9.Rett syndrome is a neurodevelopmental disorder caused by mutations inMECP2. The disease is characterized by early neurological regression followinga normal initial development. The diagnosis is a clinical one, based on majorand minor diagnostic criteria. This study, in a group of patients from asingle tertiary center, aimed to evaluate the efficiency of clinical diagnosisand to see if there was a diagnostic delay. A second aim was to investigategenotype-phenotype correlations, based on Pineda scores. In this study, sixteenpatients with a median age of 6.5 years (2.5-22 years) were included, followingmolecular confirmation of clinical diagnosis. The median age at the onset ofsymptoms and the median age at clinical diagnosis was 1.5 years and 2.5years, respectively, the difference being statistically significant. Consideringthe Rett syndrome diagnostic criteria, initially regulated in 2002 and revisedin 2010, seven and two patients in our group, respectively, did not meet themain criteria. Pineda scores among mutation groups were statistically notdifferent. To conclude, the present study revealed presence of a diagnosticdelay. The challenge may be that the patients do not exhibit full-blownclinical picture initially. No genotype-phenotype correlations were detectedin clinical severity, as measured by Pineda scores. Moreover, the diagnosticcriteria revised in 2010 are more comprehensive as compared to the 2002criteria; however, further revision may increase diagnostic sensitivity.