Evolution to permanent or transient conditions in children with positive neonatal TSH screening tests in Sergipe, Brazil

Abstract

Objectives: To assess the evolution to permanent or transient conditions in children with positive neonatal TSH tests in Sergipe, Brazil, from 2004 to 2010. Subjects and methods: Out of 193,794 screened newborns, 713 presented a neonatal TSH level higher than the local cutoff (5.2 µU/mL). From the confirmatory serum TSH values, the children were diagnosed with initial congenital hypothyroidism (CH) or suspect CH. From the evolution, they were classified as permanent CH, hyperthyrotropinemia, or transient TSH elevation. The mean incidence of each final condition was calculated for the total period of time. Results: The initial diagnosis included 37 CH (18.1%) and 167 suspect CH (81.9%) cases. The final diagnosis included 46 cases of permanent CH (22.5%), 56 of hyperthyrotropinemia (27.5%), and 102 of transient TSH elevation (50.0%). Out of the 37 cases of initial CH, 23 (62.2%) had permanent CH, nine (24.3%) had hyperthyrotropinemia, and five (13.5%) had transient TSH elevation. Out of the 167 suspect CH cases, 23 (13.8%) had permanent CH, 47 (28.1%) had hyperthyrotropinemia and 97 (58.1%) had transient TSH elevation. The mean incidence after the follow up was 1:4,166 for permanent CH, 1:3,448 for hyperthyrotropinemia, and 1:1,887 for transient TSH elevation. Eighty-six percent of the children with an initial diagnosis of CH and 41.9% with suspect CH had a permanent condition (CH or hyperthyrotropinemia). Conclusions: The follow-up of children with an initial diagnosis of CH or suspect CH is necessary to determine whether the disorder is permanent because predicting the evolution of the condition is difficult. Arch Endocrinol Metab. 2016;60(5):

Predictive factors for the diagnosis of permanent congenital hypothyroidism and its temporal changes in Sergipe, Brazil – A real-life retrospective study

“…Another important finding of the current work is the significant increase of the incidence of PCH and TCH comparing the 2004-2010 and the 2011-2015 periods in the same region, without demograph-ic changes, with the same iodine intake, the same screening procedure, and the same cutoff point in both periods (21). A similar increase was also demonstrated in Ireland over a period of 37 years.…”

“…The inclusion criteria were neonatal TSH (measured by the immunofluorimetric method, AutoDELFIA, Perkin-Elmer, Life-Sciences, Turku, Finland) higher than 5.2 µU/mL and confirmed serum TSH above 4.2 µU/mL (21). The exclusion criteria were absence of medical records in the outpatient facility of the University Hospital; loss of follow-up before the final diagnosis; and children with a final diagnosis of hyperthyrotropinaemia after the measurement of fT4.…”

“…In a previous paper, we found that among children with serum initial TSH levels greater than 10 μU/mL (more than two-thirds of the cases had PCH), 13.5% had TCH. In children with initial serum TSH levels greater than 4.2 μU/mL and less than or equal to 10 μU/m, 13.8% had PCH, while 58.1% had TCH (21). The main objective of the present study was to assess predictive factors for the diagnosis of permanent congenital hypothyroidism in a newborn with abnormal neonatal blood spot TSH.…”

“…The Brazilian Health Ministry Policy established in 2001 the University Hospital of the Federal University of Sergipe (HU-UFS) as the unique entity to perform the NSP in the State of Sergipe, which has used the same cutoff point of neonatal bloodspot TSH (5.2 μU/mL) since its implementation. This allows an appropriate comparison of different time periods (19)(20)(21). In a previous paper, we found that among children with serum initial TSH levels greater than 10 μU/mL (more than two-thirds of the cases had PCH), 13.5% had TCH.…”