Newborn Screening for Congenital Hypothyroidism and Congenital Adrenal Hyperplasia

Abstract

Objective: The Task Force formed by ICMR aimed at studying the prevalence of congenital hypothyroidism and congenital adrenal hyperplasia, the template disorders included in all newborn screening programs, and to evaluate the unidentified challenges in its execution in health care services. It also intended to evaluate the feasibility of newborn screening with regards to different geo-ethnic regions from India.

Methods: Five metropolitan centers identified had further 2 to 11 centers; both the urban and the rural sectors were included and were considered representative of the northern, southern, eastern, western and central parts of the country. A uniform protocol was developed to screen 100,000 neonates (20,000 from each center) beyond 34 wk of gestation for congenital hypothyroidism and congenital adrenal hyperplasia. Samples were collected by heel prick after 24 h of age. The parameters studied were prevalence of these diseases, percentage births covered, the turnaround time, recall rate and follow up of identified neonates as feasibility indicators. All centers participated in the Newborn Screening Quality Assurance Programme (NSQAP), of CDC, Atlanta, USA.

Results: In the participating hospitals attached to the centers, 151,765 babies were intramural births. Of these 143,344 (94.5%) babies were eligible for screening. Amongst these births, a sample of 104,094 (73.2%) babies could be covered by the personnel. Overall prevalence of congenital hypothyroidism (CH) was 1 in 722 births; if babies with transient hypothyroidisms were excluded the prevalence was calculated to be 1:1130. The collective prevalence of congenital adrenal hyperplasia was 1 in 5762 with marked regional differences.

Conclusions: This collaborative study has demonstrated the feasibility of establishing a network of committed laboratories and scientists for executing newborn screening. This is expected to have a potential impact on morbidity and mortality and therefore this should be immediately taken up in a national newborn screening program.

Keywords: Congenital adrenal hyperplasia; Congenital hypothyroidism; India; Newborn screening.