Thyroid Dysfunction in Patients With Nephrotic Syndrome

Nephrotic syndrome (NS) is one of the most popular glomerular diseases all over the world It result in loss of various macromolecules which exist in the plasma and bound to plasma proteins. They are carried away and lost in the urine due to increase glomerular membrane permeability.The abnormalities arising as a result of persistence of generalized edema , substantial heavy proteinuria >3,5 gm/24 h 3, hypoalbuminemia<30 g/L and hyperlipidemia Also, nephrotic syndrome may associated with thromboembolism and increase risk of infection, vitamin D deficiency, Iron deficiency and endocrine abnormalities such as primary Hypothyroidism.The interaction between kidney and Thyroid hormone is an important factor in the normal functioning of both the vital organs, thyroid hormone play a major role in early development of kidney structurally and regulation of major glomerular and tubular function and water and electrolytes balance .Kidneys on other hand are important in the metabolism and elimination of Thyroid Hormone.The effect of nephrotic syndrome on thyroid function can be explained by presence of proteinuria and loss of Thyroid binding globulins (TBG) in urine

which lead to decrease in Total T3,Total T4,free T3 and free T4 and consequently increase in TSH from the pituitary gland with over function of thyroid gland in order to maintain Thyroid hormone levels. Another theory explain association between nephrotic syndrome and thyroid dysfunction is Autoimmunity which can attack both organs and may also cause abnormal function of both organs. Thus, subclinical Hypothyroidism and overt Hypothyroidism may happen in NS patients and CKD patients