Introduction: The main reason for Newborn screening (NBS) for congenital adrenal hyperplasia (CAH) is to prevent adrenal insufficiency that can lead to life-threatening conditions. On the other hand, screening programmes are not always sensitive and effective enough to detect the disease. We aimed to evaluate the specificity, sensitivity and efficiency of the national NBS for CAH in Lithuania.
Methods: retrospective study was performed on the data of 88 patients with CAH from 1989 to 2020. Patients with confirmed CAH were divided into two groups: 1) 75 patients diagnosed before NBS: 52 cases with salt-wasting (SW), 21 with simple virilising (SV) and 2 with non-classical (NC) form; 2) 13 patients diagnosed with NBS: 12 cases with SW and 1 case with SV form. For the evaluation of NBS effectiveness, data of only male infants with salt-wasting CAH were analyzed (n = 36, 25 unscreened and 9 screened). Data on gestational age, birth weight, weight, symptoms, and laboratory tests (serum potassium and sodium levels) on the day of diagnosis, were analyzed.
Results: The 158 482 neonates were screened for CAH from 2015 to 2020 in Lithuania. After the establishment of NBS since 2015, CAH was confirmed in 13 patients (12 SW, 1 SV form), no false negative cases were found. The sensitivity and specificity of NBS programme were 100%. There were no significant differences between unscreened and screened male infant groups in terms of age at diagnosis (19.13 ± 7.156 d. vs. 15.44±7.79 d., P = 0.189), serum potassium (7.7±1.5 mmol/l vs. 6.89±1.5 mmol/l, P = 0.180) and serum sodium (124.5±9.7 mmol/l vs. 126.31±8.99 mmol/l, P = 0.64) levels. Significant differences were found in weight at diagnosis between the groups (-1.67±1.12 SDS vs. 0.046±1.01 SDS of unscreened and screened patients respectively, P = 0.001). Eight (32%) of 25 unscreened patients and 2 (22.2%) of 9 screened patients were treated in the Neonatal intensive care unit (P = 0.58).
Conclusion: During NBS for CAH, the sensitivity and specificity of the programme increased to 100% and there were no false-negative cases. Weight loss was significantly lower and the weight SDS at diagnosis was significantly higher in the group of screened patients.
22 Sep 2021 - 26 Sep 2021