Thyroid profile reference limits and normal values for adult and geriatric population of Taita-taveta County, Kenya

Abstract

Reference interval limits for thyronine (TSH), thyroxine (T4) and triiodothyronine (T3) for geriatrics of the world including those of geriatrics of Taita-Taveta County, Kenya are limited. The aim of this study was to develop the 95% reference interval limits for thyronine (TSH), total thyroxine (T4), and total triiodothyronine (T3) for adults and geriatrics of Taita-Taveta County, Kenya. Two hundred and forty four referent individual randomly recruited from the four sub-county of Taita Taveta (Mwatate, Wundanyi, Voi and Taveta) County, Kenya participated in this reference interval limits development study. These referents had no history of thyroid gland diseases, were not on medication for thyroid diseases, and medications that affect the hypothalamus-pituitary-thyroid gland axis. These referents were free from HIV/ AIDS, syphilis, hepatitis B and C, and pregnancy. The serum used for the measurement of thyronin (TSH), total tetraiodothyronine (thyroxine [T4]) and triiodothyronine (T3) was obtained from blood which had been drawn from the vein of the 244 referent participants between 7-10 am after 8 to 12 hours of fasting recruited between May 2015 and December 2017. TSH, T4 and T3 were measured on a quality controlled calibrated Chemwell Auto-Analyzer machine using the principle that combines an enzyme immunoassay sandwich method with a final fluorescent detection (enzyme linked fluorescent assay (ELFA)