Epidemiology of Rett syndrome in Serbia: prevalence, incidence and survival.

BACKGROUND: Rett syndrome (RTT) is a severe neurodevelopmental disorder that represents the second most common cause of mental retardation in females. However, incidence and prevalence of RTT are scarcely reported.

METHODS: A retrospective study included all patients with RTT diagnosed between 1981 and 2012 in Serbia. Estimation of incidence and prevalence was calculated on the basis of vital statistics reported by Statistical Office of Republic of Serbia.

RESULTS: From 1981 to 2012, RTT has been diagnosed in 102 girls in Serbia. Incidence of RTT in Serbia is estimated at 0.586:10,000 female live births. We estimated the prevalence of RTT in population of females younger than 19 years at 1:8,439. Death occurred in 19 patients (18.63%), with pneumonia as the most common cause. The lethal outcome by the age of 12 years could be expected for 11% of patients. The mean age at diagnosis was 3.5 years and we have confirmed a significant trend towards earlier dianosis during studied period.

CONCLUSIONS: Rett syndrome incidence in Serbia is in accordance with reports from other countries. Serbian RTT patients have increased risk for early death when compared to patients in more developed countries, most commonly due to pneumonia. There was significant trend towards early diagnosis of RTT in Serbia over recent decades.