SUN-201 Thyroid Function Screening in Preterm Infants: A Quality Improvement Project

Abstract Disclosure: R. Newfield: None. M. Amin: None. J. Sanchez: None. L. Rose: None. J. Carroll: None. T. Glenn: None. Background:Premature infants are at risk for hypothyroidism due to an immature hypothalamic-pituitary-thyroid axis, thyroid metabolism, along with illness and medication exposures. There is delayed thyroid stimulating hormone (TSH) elevation in 50% of preterm infants. Therefore, congenital hypothyroidism (CH) may be masked and missed in premature infants with normal newborn screens without further thyroid screening. The AAP recommends repeat testing in this vulnerable population. Objective:The purpose of our quality improvement project is to increase the percentage of high-risk premature infants (birth weight (BW) <1500g or gestational age (GA) <32 weeks) screened in the NICU with thyroid function tests (TFTs) evaluated by 16 days of life (DOL). Baseline data from January 2022 to June 2024 revealed only 3 of 116 eligible infants (2.6%) had TFTs by 16 DOL. Our SMART Aim is to increase the percentage of high risk premature in a level IV NICU screened in with TFTs by 16 days of life (DOL) from a baseline of 2.6% to at least 50% by March 31, 2025. Design/Methods:Our primary outcome measure is TFTs sent by 16 DOL in eligible patients. Our screening algorithm included checking TFTs at 7+/-2 DOL, 14+/-2 DOL, 3-4 weeks of life, and 36 weeks corrected gestational age for eligible patients. TFTs including TSH and Free T4 to diagnose both primary, central, or secondary causes of hypothyroidism. TFTs were drawn with routine NICU labs. Results:We met our primary goal having screened 24/26 (92%) of eligible patients from July to December 2024. Additionally, we identified and treated 4 patients for hypothyroidism since the implementation of our screening. Of these, 3 were screened by 16 DOL. Causes of hypothyroidism included 2 patients with iodine exposure through contrast and 1 patient with central hypothyroidism confirmed at the 3-4 week screen. When initiating our screening, a patient was screened at 35 DOL and found to have transient primary hypothyroidism. A fifth patient was screened elsewhere at 2 weeks and diagnosed at 4 weeks of life with CH. In our NICU, the etiology was found to be a homozygous DUOX 2 mutation. Future planned PDSA cycles include changes to the progress note templates and adding TFTs to the NICU order sets.Conclusions: The implementation of a standardized thyroid screening protocol for premature infants <1500g and <32 weeks gestational age can identify congenital and acquired hypothyroidism that may be missed with a normal newborn screen. Presentation: Sunday, July 13, 2025