Abstract
The activities of urinary dipeptidyl aminopeptidase iv (U-DAP IV) and N-acetyl-β-D-glucosaminidase (U-NAG) were determined in 11 non-insulin dependent diabetics (NIDDM) without proteinuria (DP (-)), 6 NIDDM with proteinuria (DP (+)), 27 patients with impaired glucose tolerance (IGT) and 15 normal controls. We evaluated only subjects in their forties to minimize the influence of the age factor.
U-DAP IV levels in DP (+), DP (-), and IGT patients (34.5±31.6, 11.8±5.3, 7.2±1.4μmol/mg. creatinine, mean±SD, respectively) were significantly higher than that in controls (5.7±0.8). On the contrary, the U-NAG level in DP (+) was significantly higher than that in controls, but there was no significant difference in U-NAG level between controls and DP (-) or IGT.
In IGT, DP (-), and DP (+), significant correlations were found between U-DAP IV and U-NAG levels. Six of 27 1GT (22%), four of 11 DP (-)(36%), and two of six DP (+)(33%) showed normal U-NAG and high U-DAP IV levels, but none had normal U-DAP IV and high U-NAG levels.
These results suggest that the determination of U-DAP IV may be more useful than that of U-NAG for the early detection of diabetic glomerulopathy.
