PROBLEMS AND STRATEGIES IN NEONATAL SCREENING FOR CONGENITAL HYPOTHYROIDISM IN A DEVELOPING COUNTRY

Abstract

Neonatal screening in India poses more of organizational and socioeconomic rather than medical challenges. Based on our data on hypothyroid infants and pilot study of 450 cord sera, the plan for screening considered cord TSH 80 as suggestive, with recall by home visits. Of the 17240 live births only 12407 cord sera were collected. Envisaging follow up difficulties, T4 was assayed in cord sera when TSH was > 30 μu/ml. 2.81% (350) babies needed recall. Only 30% of 302 (2.43%) babies with cord TSH 30 to 80 responded to recall letters and were normal; availability of both cord TSH and T4 helped in excluding hypothyroidism in majority of nonrespondents. 48 (0.38%) newborns had TSH > 80 μu/ml; 80% of this group and 100% with TSH > 100 were traced by home visits. Hypothyroidism was confirmed in 5/48, biochemically and by thyroid scan. All 5 hypothyroids had cord TSH > 300. The incidence in this nonendemic region of India was 1:2481. Thus false elevation of cord TSH 80 to 300 μu/ml was noted in 0.34% with a chance of detecting a hypothyroid 1 in 10 when TSH > 80. Maternal TSH of these newborns were normal. The approximate cost of screening per newborn was Rs.9.14. Screening strategies in a developing country besides other requirements must ensure meticulous clerical assistance, co-operation and education of nurses and parents, precise and cost effective technics and facilities for continued surveillance of detected hypothyroids.