Abstract

Objective

Neonatal screening for congenital adrenal hyperplasia (CAH) was implemented nationwide in Türkiye in 2022. We assessed the performance of this screening program during its first year.

Method

This retrospective, descriptive study included neonates born in Türkiye between January 1 and December 31, 2022, with gestational age ≥32 weeks and birth weight ≥1500 grams. The screening protocol used a two-tier approach. In the first step, 17α-hydroxyprogesterone (17OHP) levels were measured using fluoroimmunoassay (FIA) in dried blood spots (DBS) collected at 3-5 days of life. Infants with positive results underwent second-tier testing using liquid chromatography-tandem mass spectrometry to measure 17OHP, 21-deoxycortisol (21DF), cortisol (F), and 11-deoxycortisol (S) in DBS. Those with a steroid ratio (21DF+17OHP)/F ≥1 were referred to pediatric endocrinology clinics for diagnostic evaluation.

Results

Of 1,096,069 neonates screened (including 149,652 refugees), second-tier tests were performed on 70,455 (6.88%) infants, and 3,429(0.27%) were referred to clinics, resulting in 91 confirmed cases of classic 21-hydroxylase deficiency (21OHD) CAH (77; salt-wasting, 14; simple virilizing). Twenty two patients diagnosed with non-classical 21OHD CAH. The frequency of classic 21OHD was 1 in 12,044. The first-tier FIA-17OHP values were below 17.5 ng/mL in 99.8% of healthy neonates with ≥36 weeks gestation or ≥2500 grams and below 50 ng/mL in those with 32-36 weeks or 1500-2500 grams. Using refined cut-offs could reduce referrals by 6 times and eliminate second-tier testing for 95% of infants.

Conclusion

Neonatal CAH screening facilitates early diagnosis of 21OHD and improved patient care. Ongoing evaluation can enhance the efficiency and cost-effectiveness of the screening protocol.