Journal of Scientific Research ISSN 0555-7674 Vol. XXXVIII No. 1, June, 2008 SERUM CONCENTRATION OF THYROID HORMONES AND THYROTROPIN IN NON-GOITROUS PATIENTS Humaira Rasheed 1 , Shan Elahi 2 , Muhammad Naeem 2 , Mariam Shahid 3 and Nayab Batool Rizvi 4 1 Chemistry Department, University of Engineering & Technology, Lahore 2 Centre for Nuclear Medicine (CENUM), PO Box No.53, Mayo Hospital, Lahore 3 National Centre of Excellence in Molecular Biology (CEMB), Thokar Niaz Baig, Lahore 4 Institute of Chemistry, University of the Punjab, New Campus Lahore Summary: Thyroid related hormones were analyzed in 840 non-goitrous patients (female 616, male 224) referred to Centre for Nuclear Medicine, Mayo Hospital, Lahore. The mean (+ SD) age of patients was 30.3 + 14.1 year with age range 1 to 95 year. More than 70% of the patients had either of FT 4 , FT 3 or TSH concentration and 60.1% patients had all thyroid related hormone within normal laboratory range. The mean (+ SD) FT 4, FT 3 and TSH levels in normal patients were 15.8 + 2.7 pmol/L, 3.5 + 0.7 pmol/L and 1.6 + 0.9 mIU/L respectively. 70(8.3%) patients had either hyperthyroidism or hypothyroidism with no gender based difference. Incidence of hypothyroidism was slightly more than hyperthyroidism (4.6% VS 3.7%) in these patients. This difference was more pronounced in female as compared to male patients (5.2% VS 4.1%). In female patients hypothyroidism increased from 5% to 8% with advancement of age. Key Words: Goiter, Iodine deficiency, Thyroid Hormones, Hypothyroidism, Introduction Thyroid is an important endocrine gland in human body. The two major thyroid hormone triiodothyronine (T 3 ) and tetraiodothyronine (T 4 ) are synthesized in thyroid gland by successive incorporation of iodine ions in thyroglobuline. Iodine is an essential component of the thyroid hormones (Delange 1994). The process of iodine absorption, synthesis and release of thyroid hormones is controlled by the thyroid stimulating hormone (TSH) produced by pituitary. Thyroid hormones play its role in the cellular metabolism, growth and development. Serum thyroid hormones are strongly bound to proteins. Free fractions of T 4 and T 3 are very low as compared to circulating hormones and are responsible for the biological activity of thyroid. Their serum concentrations depict the true thyroid status. Goiter is the most visible and well known thyroid abnormality. A goiter indicates an adaptive response of thyroid gland in the face of iodine deficiency or a dysfunction in thyroid hormone synthesis (Wayne et al 1964; Laurberg et al, 2000). Iodine deficiency of the same degree may give rise to goiter in some individuals and not in others depending For Proof and Correspondence: Humaira Rasheed