Studies on urinary gamma-glutamyl transpeptidase in nephrotic syndrome patients.

(1) Variations in the levels of GGT were measured in urine specimens taken in the early morning in control and in 20 consecutive adult patients with uncomplicated nephrotic syndrome. (2) The urinary GGT activity was increased in all cases of nephrotic syndrome patients investigated with different etiology. (3) A significant correlation was found between urinary GGT activity and serum albumin (r = 0.727) but not with serum cholesterol (r = 0.129). (4) These findings suggest that enhanced excretion of urinary GGT may be stimulated by decreased albumin concentration or oncotic pressure but does not appear to be due to leakage from plasma. (5) A systematic study on urinary GGT showed that GGT activity was decreased to the upper limit of normal control values in nephrotic syndrome patients after remission.