ESPE Abstracts

Introduction and Aim: In this study, we aimed to investigate the admission characteristics, the ratio of permanent/transient hypothyroidism, and the predictors of permanent or transient hypothyroidism at initial evaluation in newborns admitted in 2013 and 2014 from neonatal TSH screening program.

Method and Results: During two years period, 985 babies were admitted to our clinic with screening results for evaluation, and L-T4 treatment was started for 73 patients (7.4%). The median age at admission was 21 days (25p-75p;14-33). The median age at presentation and treatment initiation were 20 days (25p-75p;15.5-30.5) and 30 days (25p-75p;17-63), respectively. There was no statistical difference between the TSH screening values from heel prick between 912 babies recalled from screened and no treatment was required and 73 patients who needed treatment (p:0.80). The TSH values in the 1st and 2nd heel pricks blood in treated group were 14.7 mIU/L (25p-75p;7.2--27.3) and 10 mIU/L (25p-75p;7.1-22.5), respectively. When the patient were evaluated for etiology after 3 years of L-T4 treatment, 32 (42%) (14 male) patients had permanent hypothyroidism. Thyroid dysgenesis was detected in 7 patients (22.5%) (2 agenesis, 5 ectopic thyroid tissue). A significant difference was found between the permanent and transient hypothyroidism groups for the 1st(23.5 mIU/L (25p-75p;9,65-43,6) and 12,3 mIU/L (25p-75p; 6,42-22,67) respectively.) and 2nd heel blood TSH(14,85 mIU/L (25p-75p; 7,6-44,75) and 8,6 mIU/L (25p-75p; 6,35-15,85) respectively.) and venous TSHs(23,8 mIU/L (25p-75p; 10,25-118) and 12,29 mIU/L (25p-75p; 8,41-27,84) respectively.)(p:0.009; p:0.0055; p:0.0077, respectively)[ST1]. Additionally, a venous TSH of ≥17.74 mIU/L measured before the initiation of treatment was found to predict permanent CH with 61.2% sensitivity and 66.6% specificity. Treatment was initiated after checking venous TSH and fT4 for 1.5±0.92/1.8±0.94 times In permanent/transient hypothyroidism groups (p:0.11). While 19 (44%) of 43 patients who were treated according to the first venous TSH and fT4 values had transient hypothyroidism, 23 (76.6%) of 30 patients with treatment intiation after multiple samples had transient hypothyroidism (p:0.0057).

Summary of Results: L-T4 treatment was initiated in 7.4% of infants who were recalled from the newborn TSH screening program, and 42% of these infants were subsequently diiagnosed with permanent hypothyroidism. An initial venous TSH of ≥17.7 before treatment initiation was found to be predictive of permanent CH. In addition, the need for multiple sampling to make a treatment decision was found to be predictive of transient CH.