There is a certain number of people with diabetes who have decreased GFR without albuminuria. Diabetic kidney disease is comprehensive concept including typical and atypical diabetic nephropathy including such cases. However, it is still unknown which histological parameters precisely predict increased albuminuria or reduced GFR in persons with type 2 diabetes. To address this, we hypothesized that index of arteriolar hyalinosis (IAH) could be a predictor for onset of macroalbuminuria and eGFR<60 mL/min/1.73 m2 (chronic kidney disease, CKD) during early diabetic nephropathy. The subjects consisted of 34 persons with type 2 diabetes (22 men; age, 46±9 years; eGFR 92.4±18.2 mL/min/1.73 m2, 17 normoalbuminuria, 17 microalbuminuria) who underwent percutaneous renal biopsy. These subjects were divided into 3 groups, onset of macroalbuminuria in advance (MA; n=9), onset of eGFR<60 in advance (G; n=8) and no onset of CKD (C; n=17) during the observation period (19±6 year). Light and electron microscopy-based morphometric analyses were performed to quantitatively evaluate glomerular and interstitial structural changes. There was no difference in age, sex, duration of diabetes, HbA1c, eGFR, blood pressures at the baseline among 3 groups. Urinary albumin was significantly increased in MA than G and C groups (p=0.034, 0.001, respectively). The IAH was significantly larger in MA (1.95±0.70) than G (1.41±0.44, p=0.049) and C (1.37±0.49, p=0.014) groups while other histological parameters did not reach significant extent. The logistic analysis indicated that IAH score and urinary albumin are associated with MA (p=0.028 and p=0.015, respectively). Multiple regression analysis revealed that arteriolar hyalinosis (p=0.042) and urinary albumin (p=0.025) were associated with MA group.
In conclusion, persons with type 2 diabetes having macroalbuminuria prior to reduced GFR tend to have arteriolar hyalinosis at the baseline.
A. Suzuki: None. T. Moriya: None. M. Matsubara: None. A. Hayashi: None. T. Miyatsuka: None.
