Newborn Screening for Cystic Fibrosis in Mersin Province: Yearly Assessment of the National Program

Abstract

OBJECTIVES: A national newborn screening program for cystic firosis (CF) was started using immunoreactive trypsinogen (IRT) test onJanuary 1, 2015, in Turkey. We aimed to analyze the characteristics of newborn screen-positive (NBSP) infants in Mersin province.MATERIALS AND METHODS: The data on NBSP infants were retrospectively analyzed between 2015 and 2017 from records of MersinWomen & Children's Hospital and Mersin City Training and Research Hospital.RESULTS: A total of 82,273 newborns were screened for CF by IRT test between January 2015 and December 2017 in Mersin. Amongthose, 512 infants were defied as NBSP after two repeated IRT tests (IRT/IRT) (138 infants in 2015, 217 in 2016, and 157 in 2017). Sweattest was normal in the majority of infants (115 infants [83.3%] in 2015, 189 [87.1%] in 2016, and 129 [82.2%] in 2017). Overall, between 2015 and 2017, after two repeated sweat tests, 4 infants had sweat test results in the intermediate range and 9 infants had positivesweat tests. The incidence of CF for a 3-year period was approximately 1/9300 in our region. The positive predictive value of IRT test fordefiing CF was 1.8%, with a sensitivity of 90.0% and specifiity of 99.4%.CONCLUSION: IRT/IRT test as a newborn screening strategy provides the opportunity for earlier diagnosis and treatment of CF patients.More data are needed to understand the frequency of CF on a national level.