Aug 1, 2007 · Hyperthyrotropinemia is characterized by high TSH concentrations in the neonatal period with normal concentrations of T 4 and FT 4. It may be caused by a transient or permanent thyroid...

Newborn screening (NBS) for congenital hypothyroidism (CH) started in the 1970s, with the introduction of radioimmuno assays (RIA) for the measurement of thyroxine (T4), and thyroid stimulating hormone (TSH).

Specifically we derived age and gender stratified RIs for free thyroxine (fT4) and thyroid stimulating hormone (TSH) which had been analyzed on a Roche e601 analyzer from 2011 to 2013. Determination of reference intervals was done using a non-parametric method.

Congenital hypothyroidism (CH) causes neuronal migration disorder due to thyroid hormone deficiency and serious CH delays psychomotor development. CH is preventable by early detection and treatment. Newborn screening (NBS) is performed worldwide and …

Nov 1, 2010 · Thyroid-stimulating hormone (TSH) surges soon after birth, resulting in thyroxine (T4) concentrations that are higher in the first postnatal week than at any other time of life and in circulating triiodothyronine (T3) concentrations that are three to four times higher than in the fetus.

Oct 25, 2018 · TSH and FT4 were substantially high in the first 24 h after birth followed by a rapid decline over the subsequent 168 h. Use of hour-based RIs in newborns allows for more accurate identification of neonates who are at risk of hypothyroidism.

May 19, 2023 · The CALIPER TSH upper limit of 4.409 µIU/mL would result in 145 (11.9%) neonates in the current study being classified as having elevated TSH compared to 29 (2.4%) using our sex and age specific RIs.

Jul 17, 2020 · The neonatal TSH percentile charts were created by calculating in healthy neonates the 10, 25, 50, 75, 90, 95, 97.5, and 99th percentiles of TSH according to sex and neonatal age. Arithmetic TSH values were transformed to a natural logarithm scale to approximate the normal distribution.

Aug 1, 2019 · There is wide variation in thyroid-stimulating hormone (TSH) cutoffs used by NBS programs. Data on TSH reference ranges in preterm infants at increasing postnatal age are limited. Our study objective was to determine TSH reference ranges for preterm infants born at <32 weeks’ gestation.

Normalization of the TSH levels in the first one month indicates transient neonatal hyperthyrotropinemia. In other cases, increased TSH levels persist for 6 months. However, TSH response against TRH may be found to be increased for 3-7 years.