Endocrine Abstracts

Introduction: Interaction of growth hormone system with Hypothalamic pituitary axis can be complicated, and the effect of GH treatment on thyroid function is still not completely clear. GH has inhibitory effect on conversion of T4 to reverse T3, while enhancing extrathyroidal conversion of T4 to T3.

Objective: To assess thyroid function test in patients with growth hormone deficiency, receiving growth hormone replacement therapy in Slemani, Kurdistan region of Iraq.

Methodology: A prospective follow up study carried out in Endocrine and Diabetic Center in Slemani from October 2014 to October 2015, on a convenient sample of 54 patients with growth hormone deficiency. The patients were followed up to check thyroid function tests (TSH, T3 and T4) at the end of 1, 3, 6, 9 months of GH replacement therapy.

Results: Mean age of studied patients was 14±3.4 years and males were more than females. There was a significant increase in TSH level after 6 months of treatment with GH (P=0.02). No significant differences were observed in T3 level after 9 months of GH treatment (P=0.9). A significant decrease in T4 level was observed after 9 months treatment with GH (P=0.03).

Conclusions: Thyroid hormone T4 of patients with growth hormone deficiency declined while thyroid stimulating hormones increased after growth hormone replacement therapy.