Diabetic Nephropathy Accompanied by Iodine-Induced Non-Autoimmune Primary Hypothyroidism: Two Case Reports.

Abstract

Abstract.We reported 2 diabetic patients with nephrotic syndrome due to advanced diabetic nephropathy complicated by non-autoimmune primary hypothyroidism. Hypothyroidism developed along with the anasarcous status. Histological examinations of the thyroid gland revealed almost normal thyroid follicles without lymphocytic infiltration.The amounts of thyroid hormone lost into the extravascular space such as in urine and ascites were not sufficient to cause hypothyroidism alone. Serum total iodine levels measured during the hypothyroidal state in both cases were definitely elevated, and the perchlorate discharge test of both cases showed positive discharge (24 and 34%, respectively). The thyroid functions normalized after iodine restriction in the first case and initiating hemodialysis in the second case, in parallel with normalization of serum total iodine levels. These findings suggest that impaired renal handling of iodine resulting in elevation of serum iodine levels, rather than an autoimmune mechanism or extravascular hormone loss, played a principal role in the development of primary hypothyroidism found in these 2 patients, probably through a prolonged Woli Chaikoff effect. secondary to diabetic neuropathy and peripheral vascular disease have been recognized. However, the etiology that plays a major role in accelerating extravascular fluid retention has yet to be elucidated. Hypothyroidism is commonly associated with extravascular fluid retention through increased capillary transudation of protein associated with decreased cardiac output and renal blood flow [3]. Therefore, deterioration of the anasarcous status may occur when hypothyroidism develops in cases showing a preexisting nephrotic state. We reported here, 2 diabetic cases of nephrotic syndrome due to advanced diabetic nephropathy complicated by nonautoimmune primary hypothyroidism, in which hypothyroidism developed along with deterioration of the anasarcous status and was likely caused by an intrathyroidal iodine organification defect.

Iodine-Induced Hypothyroidism

“…The thyroid abnormalities in these patients included, thyroid enlargement, normal or elevated thyroid RAI uptakes, positive perchlorate discharge tests, and absence of lymphocyte infiltration. Two patients with diabetic nephropathy developed iodine-induced nonautoimmune hypothyroidism that was reversed after iodide restriction in one patient and hemodialysis treatment in the other (49). However, in another study, no relationship was found to exist between thyroid abnormalities to iodide retention and application of iodide-containing antiseptics (50).…”

Evaluation of thyroid function in diabetes mellitus in Calabar, Nigeria

“…The influence of other endocrine and non-endocrine organs other than the pancreas on diabetes mellitus is documented (1,2,3). Occasionally other endocrine disorders such as abnormal thyroid hormones levels are found in diabetes mellitus (4,5).…”

Hypothyroidism due to nephrotic syndrome: a notable clinical entity

“…There have been some reports on the development and exacerbation of hypothyroidism in adult patients with NS [3,[12][13][14][15]. In most of these reports, hypothyroidism, due to Hashimoto's disease, total thyroidectomy for Graves' disease, radioiodine treatment for Graves' disease, or lobectomy for benign nodules, existed as an underlying disease before the onset of NS.…”