The purpose of this study was to relate severity of illness at 1, 7, 14, and 28 postnatal days in preterm infants groups, 23-27 (n = 73), 28-30 (n = 160), and 31-34 (n = 208) wk gestation, to the corresponding sera levels of T4, free T4, T4-binding globulin, TSH, T 3, rT3, and T4 sulfate. The British Association of Perinatal Medicine and Neonatal Nurses Association 1992 scoring categories (published elsewhere) were used as an index of illness severity: level 1 (maximal intensive care) was compared with level 2 (high-dependency intensive care) combined with level 3 (special care); infants were scored on 1, 7, 14, and 28 postnatal days. In level 1 infants, there were significant reductions in T3 at 7 d (28-30 wk), 14, and 28 d (23-27 and 28-30 wk); T 4 at 7, 14, and 28 d (23-27 wk); at 14 and 28 d (28-30 wk); and at 7 d (31-34 wk); and free T4 at 14 d (23-27 wk). TSH was unchanged in all groups at all ages and with reductions in T4 and T3 being the key features of severe illness in extreme preterm infants. Copyright

doi.org/10.1210/jc.2004-2091, hdl.handle.net/1765/58812
Journal of Clinical Endocrinology and Metabolism
Department of Internal Medicine

Simpson, J., Williams, F., Delahunty, C., van Toor, H., Wu, S.-Y., Ogston, A., … Hume, R. (2005). Serum thyroid hormones in preterm infants and relationships to indices of severity of intercurrent illness. Journal of Clinical Endocrinology and Metabolism, 90(3), 1271–1279. doi:10.1210/jc.2004-2091