Neonatal screening for congenital adrenal hyperplasia: 17-hydroxyprogesterone cut off values based on birth weight Devi V. Rajeswari1, Malar R Jothi2,*, Silambanan Santhi3, Jamir Sungdirenla4 1PG Student, Dept. of Biochemistry, Sri Ramachandra Medical College and Research Institute, Chennai, 2Professor, Dept. of Biochemistry, Sri Ramachandra Medical College and Research Institute, Chennai, 3Professor & HOD, Dept. of Biochemistry, Sri Ramachandra Medical College and Research Institute, Chennai, 4Senior Resident, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India *Corresponding Author: Email: drjothimalar@gmail.com
Online published on 2 January, 2019. Abstract Introduction Congenital adrenal hyperplasia (CAH) is an adrenal disorder, most commonly caused by 21-hydroxylase enzyme deficiency. Newborn screening for CAH is done by the measurement of 17-hydroxyprogesterone (17-OHP). Aim To establish the reference limits of 17-OHP in newborns. Materials and Methods The study was conducted at Sri Ramachandra Medical College and Research Institute (SRMC& RI), Chennai. The clinical data of 360 neonates delivered over a period of two years from January 2015 to December 2016 were retrospectively analyzed. The newborns were grouped according to birth-weight: G1: < 1, 250 g, G2: 1250–2249 g, G3: >2250 g. Based on birth weights 17-OHP cut-off values were determined for each group by rank number. Results The reference limits for the three group, < 1, 250 g, 1250–2249 g, >2250 g are 2.23–59.3, 1.9–29.7 and 1.9–15.1 nmol/L respectively. The upper reference limits of all the groups are less than the values showed in the kit literature. Conclusion CAH can be diagnosed by measuring 17-OHP at birth as a part of neonatal screening. Population specific and birth weight specific cut off values of 17-OHP will reduce the false positives. ¡Top Keywords Congenital adrenal hyperplasia (CAH), 17-Hydroxyprogesterone (17-OHP), Virilization, Dried blood spot (DBS), Salt-wasting. Top |