Neonatal Screening for Congenital Hypothyroidism in Nicaragua: Audit of a Cord-blood Thyrotropin-based Program (2005-2015)

Abstract The aim of this study is to evaluate the Nicaraguan screening program for congenital hypothyroidism in terms of coverage and effectiveness of detection and confirmation of cases with the condition throughout a decade. Thyrotropin was quantified in cord-blood samples by a validated ELISA and a cut-off of 20 mU/l was applied. Coverage, positive predictive value, recall rate and prevalence were retrospectively analysed. Babies with positive screening results were contacted for confirmation by means of determination of thyrotropin and thyroid profile in serum samples. 272,338 babies were screened during the period 2005-2015. The mean coverage reached by the program in the participating departments was 71%, with a positive predictive value of 83% and a recall rate of 0.055%. Eighty cases of congenital hypothyroidism were identified, representing an incidence of 1 in 3229 live births, most of them (81%) being severe. The performance of the Nicaraguan screening program is comparable to those in Latin America also using cord-blood samples. The incidence of congenital hypothyroidism is within the low range of other countries worldwide. Strategies are needed to expand the program to the whole country, improve recall rates and achieve earlier treatment of babies, with the condition.