https://www.selleckchem.com/products/ly3009120.html Newborn screening (NBS) for congenital hypothyroidism (CH) in the Netherlands consists of thyroxine (T4), thyroid-stimulating hormone (TSH), and T4-binding globulin (TBG) measurements to detect thyroidal CH and central CH (CH-C). CH-C is detected by T4 or a calculated T4/TBG ratio, which serves as an indirect measure of free T4. TSH and TBG are only measured in the lowest 20 and 5% of daily T4 values, respectively. A recent evaluation of the Dutch NBS for CH showed that the T4 and T4/TBG ratio contribute to the detection of CH-C but also lead to a low positive predictive value (PPV). Dried blood spot (DBS) reference intervals (RIs) are currently unknown and may contribute to improvement of our NBS algorithm. RIs of T4, TSH, TBG, and the T4/TBG ratio were determined according to Clinical & Laboratory Standards Institute guidelines in heel puncture cards from routine NBS in both sexes and at the common NBS sampling ages. Scatter plots were used to compare the healthy reference population to previously png NBS sensitivity at the current level. An association between hearing impairment (HI) and congenital hypothyroidism (CH) has been reported previously. However, in general, studies were retrospective and had small sample sizes, and the results were variable and inconclusive. The aim of our study was to assess the prevalence of HI among patients with CH and to examine factors potentially predictive of HI including severity of CH, etiology of CH, and timing of treatment initiation. Audiometry was undertaken prospectively in 66 patients aged 3-21 years diagnosed with primary CH and 49 healthy matched controls. All patients with HI underwent examination by an otolaryngologist, and in patients with sensorineural loss, brainstem evoked response audiometry was performed. A next-generation sequencing (NGS) panel for genes involved in deafness was performed in patients with sensorineural HI to exclude additional genetic etiolo