Urinary sediment features in proliferative and non-proliferative glomerular diseases

Background: The studies on urine sediment particles in patients with glomerular diseases (GD) are few and have focused only on single urine particles. In this study, we investigated the prevalence and number of 12 urine sediment particles in two groups of patients, one with proliferative GD, and the other with non-proliferative GD. Methods: The urine sediment of 100 consecutive patients, with a renal biopsy-proven proliferative or non-proliferative GD and marked cylindruria, were examined a few hours before renal biopsy according to a standardized method. The urine particles investigated were erythrocytes, leukocytes, renal tubular cells, lipids and hyaline, hyaline-granular, granular, waxy, erythrocytic, leukocytic, epithelial and fatty casts. Results: Patients with proliferative GD (n=52) had both a significantly higher prevalence of microscopic hematuria, leukocyturia, tubular epithelial cells, erythrocytic casts, epithelial casts, and significantly higher amounts of erythrocytes, leukocytes, tubular epithelial cells/20 high power field (HPF), erythrocytic and epithelial casts. On the other hand, patients with non-proliferative GD (n=48) had significantly higher numbers of fatty casts. In proliferative GD, leukocyturia was associated with intracapillary and extracapillary proliferation, crescents and fibrinoid necrosis at renal biopsy. At discriminant analysis, the two types of GD could be identified with 80.8% sensitivity and 79.2% specificity. By multiple logistic regression analysis, patients with erythrocytes, leukocytes and erythrocytic casts in the urine had an odds ratio (OR) of 9.91 (95% confidence interval (95% CI): 1.01-97.51), 7.85 (95% CI: 2.77-22.20), and 4.33 (95% CI: 1.41-13.31), respectively, of having proliferative GD. Conclusions: Our examination of the urine sediment shows that proliferative GD and non-proliferative GD differ in many respects.