ESPE Abstracts

Background: Neonatal thyroid screening is considered one of the best cost-effective tool to prevent mental retardation in population. Different strategies are suggested for thyroid hormone estimation in the sample obtained at birth using cord blood or later in neonatal period. In King Abdulaziz Medical City, cord TSH is the screening tool to detect congenital hypothyroidism cases with a cut off value of 30 MIU/l considered positive result. In 2011, newborn screening programme was started and TSH in heel prick with a cut-off value of 20 uU/l was part of the programme.

Objective and hypotheses: The aim of this study is to compare the sensitivity and specificity of cord blood TSH and heel stick TSH in detecting congenital hypothyroidism.

Method: All deliveries conducted at King Abdulaziz Medical City in Riyadh region KSA during the period from May 2011 to May 2013 were included in this study. Both cord blood and heel stick samples for TSH were collected from each delivery for screening.

Results: A total of 17729 neonates were screened, of those seven were diagnosed to have congenital hypothyroidism. All of the cases were detected by both cord and heel stick TSH level. 305 neonates had positive heel-stick TSH result (sensitivity 100% and specificity 98.32%), 88 neonates had positive cord TSH result (sensitivity 100% and specificity 99.55%).

Conclusion: Both cord and heel-stick TSH detects all the cases of congenital hypothyroidism. Cord TSH is superior than heel stick as false positive rate was around three times higher in heel stick compared with cord TSH.