Renal findings and glomerular pathology in diabetic subjects

Background: To describe the relationship between proteinuria, hematuria, and renal insufficiency, on one hand, and glomerular pathology, on the other hand, in a consecutive biopsy series of diabetic patients. Subjects and Methods: All diabetic subjects (n = 200) biopsied from 1979 to 1995 at Tampere University Hospital were identified in retrospect. The clinician-based indication (any unexplained renal finding) for renal biopsy was consistent during the years and was: proteinuria alone in 68%; combined with hematuria in 10%; with renal insufficiency in 10%; with both in 9%, and with isolated hematuria or renal failure in 3%. One third of the subjects had proteinuria of greater than or equal to 3 g/24 h and 16% a serum creatinine revel of greater than or equal to 200 mu M. Glomerulopathy was found in 171 specimens and defined as nodular diabetic (group A), diffuse diabetic (group B) and primary (group C). The 24-hour urinary protein excretion rate [mean (range)] was 3.5 (1.6-6.9), 1.0 (0.5-3.5), and 3.6 (1.1-6.6) g in groups A, B and C, respectively (ANOVA p = 0.001). The corresponding serum creatinine values [mean (SD)] were 175 (115), 105 (142) and 169 (138) mu M(p = 0.001). Results: Nodular diabetic glomerulopathy was found in 40%, diffuse diabetic glomerulopathy in 42% and primary glomerulopathy in 18%. A primary glomerulopathy was found in any indication and in both types of diabetes (prevalence range 14-26%). The best multivariate logistic regression model obtained (chi(2) = 13.5, p = 0.008) in predicting the presence of diabetic glomerulosclerosis (group A + B) in contrast to a primary glomerulopathy (group C) included retinopathy (p = 0.04), renal insufficiency (p = 0.03), hematuria (p = 0.12) and type of diabetes (p = 0.10). Conclusion: In this series of diabetic subjects, biopsied due to proteinuria, hematuria and not severe renal insufficiency, 18% had evidence of a primary glomerulopathy. copyright (C) 2000 S. Karger AG, Basel.