Thyroid hormones are necessary for the growth and development of the kidney and for the maintenance of water and electrolyte homeostasis. The kidney normally contributes to the clearance of iodine, primarily by glomerular filtration. Thus iodide excretion is diminished in advanced renal failure, leading sequentially to an elevated plasma inorganic iodide concentration and an initial increment in thyroidal iodide uptake.
Materials and Methods: The present study was conducted in a tertiary care hospital in Belagavi, Karnataka State. 50 cases that were on regular maintenance hemodialysis treatment were selected and 50 controls were taken for study. Age & sex matched controls with normal renal function and no previous history of thyroid dysfunction was included in the study as controls. The quantitative determination of serum T3, T4 & TSH was done. The assay principle combines a one step enzyme immunoassay sandwich method with a final fluorescent detection (ELFA). Serum urea and creatinine was estimated by urease/glutamate dehydrogenase method and modified.
Results: There was a significant difference between the control and study group with respect to serum TSH & T3 levels, serum T4 levels were found to be not statistically significant. The serum TSH level was increased in 8 patients (16%) among those with CKD; the mean serum TSH concentration was 5.49±11.03 in CKD patients which was significantly increased than in controls (3.27±2.06). Serum T3 concentration was less than the normal range in 10 of the 50 (20%) CKD patients, the mean serum total T3 concentration was 1.69±0.67 in CKD patients was significantly lower than that in the control subjects (2.03±1.2). Serum concentration of T4 was less in cases (81.34±23.87) than in controls (101.41±19.12) but the results were statistically not significant (P=0.083).
Conclusion: The present study finds thyroid dysfunction to be very common in CKD patients and reveals the significant association between CKD progression and thyroid dysfunction and mean of T3, T4 decreases and TSH increases significantly in cases as compared to controls. The diagnosis of hypothyroidism can be easily missed in Haemodialysis patients. Timely diagnosis and treatment of hypothyroidism may prevent deterioration of the patient’s condition and prolong survival.