Congenital Hypothyroidism and Neonatal Screening: Indian Context

Congenital hypothyroidism (CH) is the most common congenital endocrine disorder with an incidence of 1 in 2000 to 1 in 4000 live births. In India the estimated incidence is 1 in 2500-2800 live births. CH can be transient or permanent. Thyroid dysgenesis accounts for 85% of the cases of permanent congenital hypothyroidism. It includes thyroid agenesis, hypoplasia and ectopy. Most of the neonates with CH are asymptomatic at birth. Presence of umbilical hernia, coarse facies, constipation, prolonged neonatal jaundice, hoarse cry, mottling, hypotonia are some of the clinical clues to suspect the disease. Worldwide, three different strategies are followed for screening CH. A heel prick blood sample collected on special filter paper card after 48 hrs to 4 days of birth is used. A positive screening test is confirmed by a venous sample. Treatment should be started within 2 weeks after birth to prevent adverse somatic and neuro developmental outcome.