ESPE Abstracts

Background: Congenital hypothyroidism (CH) is the most important cause of preventable mental retardation. Therefore, screening programme has been using for early detection of hypothyroidism in our country since 2007.

Objective: To compare clinical features of newborns with and without CH who were detected in screening programme between 2009 and 2014.

Method: This study enrolled 710 (344 Girls) newborn referred from CH-screening programme to our clinic. All newborns were examined. Serum TSH and fT₄ levels were obtained from all newborns. L-Thyroxin was prescribed and thyroid ultrasonography was performed in newborns with hypothyroidism. According to admission time to clinic, they were classified into three groups: ≤30 days, 31–90 days, ≥91 days.

Results: Group 1 consisted of 489 newborns, group 2 consisted of 181 newborns and group 3 consisted 40 newborns. Median age was 23 (18) days in study-population. CH was diagnosed in 17.4% of study-population. Neonatal TSH was 36.7±31 IU/l in newborn with (NBw) CH. There was a significant delay (2.27±1.4 month) in the normalization of serum TSH in NBwCH. There was no difference between birth weight of NBwCH and without CH. Of the 79.3% NBwCH was diagnosed in first month. Serum TSH was 17 (34.45) and fT₄ was 0.82 (0.54). LT₄ was prescribed mean 32±22 days. Ultrasonography showed that athyreosis 7%, hypoplasia 66%, 24% eutopic. Mean L-thyroxin dose was 9.3±2.3 μg/kg in athyreotic newborns, 7.6±3.1 μg/kg in hypoplasia group, and 7.0±2.0 μg/kg in eutopic group respectively. Birth weight was correlated with fT₄ (r: −0.230) in NBwCH. LT₄ dose was significantly correlated with serum TSH (r:0.505) and fT₄ (r: −0.230).

Conclusion: Our study shows that all NBwCH are not diagnosed before than first months. Deterioration of cognitive function can be seen in untreated children with CH. Presence of high neonatal TSH in screening, serum TSH should be obtained and treatment should be initiated as soon as possible.