CAH Newborn Screening in India: Challenges and Opportunities

Abstract

Congenital adrenal hyperplasia (CAH) is a common treatable disorder which is associated with life-threatening adrenal crisis, sexual ambiguity, and/or abnormal growth if undiagnosed. Newborn screening is a cost-effective tool to detect affected babies early after birth to optimize their treatment and follow-up. Newborn screening however is in its nascent stage in India where it is not yet introduced universally for all babies. The following review briefly highlights the challenges (e.g., lack of universal screening, healthcare resources) and opportunities (e.g., reduction in morbidity and early correct gender assignment in females) associated with newborn screening for CAH in a large Indian birth cohort.

Neonatal Screening for Congenital Adrenal Hyperplasia in Indian Newborns with Reflex Genetic Analysis of 21-Hydroxylase Deficiency

“…Neonatal screening for CAH in the first week is probably even more crucial than CH, as undetected and untreated babies affected with the salt loosing variety may have a crisis within a few days of birth. However, in comparison to congenital hypothyroidism, CAH screening for CYP21A2 is more complex as the steroid metabolism has many variables affecting it and false positive results increasing parental anxiety are likely unless a prompt and effective second-tier testing to confirm true positives isin place [ 16 ].…”

“…Important considerations for a newborn screening program are the detection rate, screen positive rate, and the positive predictive value of the test. In past newborn screening studies with sample sizes of more than 10,000 newborns from India, the screen positivity has ranged from 0.03% to 0.13% [ 16 ]. The positive predictive value in these studies has ranged from 16.8% to 100% [ 16 ].…”

“…In past newborn screening studies with sample sizes of more than 10,000 newborns from India, the screen positivity has ranged from 0.03% to 0.13% [ 16 ]. The positive predictive value in these studies has ranged from 16.8% to 100% [ 16 ]. In the present study, the screen positivity was 0.044%, while the positive predictive value was 55.7%.…”

“…This requires communication with the clinician and recall of the baby’s transport of the sampleand the test leading to delay in diagnosis. Moreover, though repeat 17-OHP of the venous sample is widely available, steroid profiling by MSMS is not easily available in India [ 16 ]. Molecular confirmation from the same initial Guthrie card does not require recall of the patient and resampling.…”

Newborn Screening for CAH—Challenges and Opportunities

“…Dabas and colleagues [ 2 ] report on the challenges and opportunities for CAH NBS in India. India’s high annual birth rate results in over 4 million new-borns each year.…”