Tatjana MİLENKOVİC, Rade VUKOVİC, Bojana RADOJİCİC, Katarina MİTROVİC, Sladjana TODOROVİC, Ljubica ZATEZALO

Thirty years of the newborn screening program in Central Serbia: the missed cases of congenital hypothyroidism

Newborn Screening (NS) program for congenital hypothyroidism (CH) hascompletely changed the natural history of this devastating disorder for thevast majority of children with CH. However, cases of missed CH do happen,and it is important to keep this possibility in mind during every day clinicalpractice. The objective of this study was to analyze the recognized cases ofundiagnosed CH by the NS program in Central Serbia in order to evaluate thereasons for such omissions. Data regarding the recognized missed cases of CHbetween the years of 1983 and 2013 were collected and analyzed. During 30years of the NS program for CH on the territory of Central Serbia, 1,547,122newborns were screened, and during this period, 14 children with CH weremissed by the NS. Five missed cases were children with athyreosis (35.8%),8 had ectopic thyroid gland (57.1%) and one child had dyshormonogenesis(7.1%). The median age at diagnosis of CH in these missed cases was 1.12years (range 0.08-13.5 years). In the group of children with missed diagnosisof CH, 71.4% were missed due to errors during sample collection, and 28.6%of patients were missed due to false negative screening results. Continuouseducation of neonatologists as well as nurses in neonatal units of maternityhospital are necessary to avoid errors in sample collection. It is of highimportance to notice in a discharge list if a child is referred to the hospitalbefore the sample is taken in a maternity hospital. On the other hand, thematernity hospital has to inform the screening laboratory about any child whowas referred to another hospital if the blood samples for screening are nottaken. Parents should be better informed that each child has to be includedin the NS which is obligatory in Serbia. In addition, awareness amongstpediatricians in primary care should be raised regarding the possibility ofmissed cases of CH.

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