Monitoring and Evaluation of Thyroid Function Tests, Serum Electrolytes and Creatinine Levels Before and After ¹³¹I Therapy

Background: Serum electrolytes, Creatinine, and thyroid profile play an important role in 131I treated patients of thyroid disorders. Objectives: To determine the effect of radioactive iodine (131I) on renal parameters, serum electrolytes and the correlation among TFT’S, creatinine, and chloride levels before and after I131 treatment in thyroid disorders. Methods: The study was performed on 55 patients of thyrotoxicosis with age ranging from 16-65 years (mean age= 41±14years and BMI=24.8±4.46). The significance of the differences between the results of 1st, 2nd, and 3rd-time serum analysis was assessed by paired Student's t-test. Association between parameters was assessed by Spearman correlation analysis. Results: 40 patients were taking Carbimazole, and 15 were directly recommended for I131 therapy. Strongly significant variations were observed for TFT’S (T3=0.012, T4 =0.017, and TSH=0. 001) during the follow-up treatment. Before taking I131 (Serum analyzed at 1st time), there observed negative correlation of T3(r=-.46, p=0. 002) and TSH (r=-0.31, p=0.02) with creatinine, and positive correlation of TSH(r=0.29,p=0.02) with chloride. BMI was negatively correlated with potassium(r=-0.30, p=0.02). At the 2nd time (after stopping the Carbimazole), no correlation results were observed. Two months after oral administration of ¹³¹I, creatinine, and chloride level was significantly increased (p=0.000), (P=0. 03) respectively, but had no correlation with TFT’S. Conclusion: Our findings suggest that patients with goiter (diffused or toxic) have association of TFT’S and BMI with serum electrolytes and creatinine, ¹³¹I therapy is also associated with the increase in creatinine and chloride levels of patients leading to kidney problems.