Glomerular Hematuria Research Articles

Effect of diuresis on urinary erythrocyte morphology in glomerulonephritis.

The differentiation between glomerular and non-glomerular haematuria by phase-contrast microscopy has proved to be a useful tool in the diagnosis of glomerulonephritis. In an attempt to evaluate the effect of marked diuresis on the altered red cell morphology in patients with biopsy proven glomerulonephritis, urinary sediments were examined following water or furosemide-induced diuresis. In both diuretic states urine flow increased, urine osmolality decreased and the percentage of glomerular erythrocytes was significantly reduced in the urinary sediment. These data demonstrate that the alteration in urinary red cells in glomerulonephritis is mainly caused by tubular forces. The diagnostic significance is reduced during increased diuresis and the evaluation of urinary red cell morphology should not be performed.

Red Cell Morphology as a Diagnostic Aid in Hematuria

Dried smears of urinary sediment stained with Wright's stain were examined and compared in 20 selected patients with hematuria. In ten patients with microscopic hematuria and glomerular lesions demonstrated by renal biopsy, the urinary red cells were characteristically dysmorphic and hypochromic. This was distinctly different from the red cell morphology in ten patients with nonglomerular causes of hematuria, which was more like peripheral blood. The pathogenesis of the changes in red cell morphology seen in glomerular hematuria is unknown, but it appears not to be due to the urine composition per se. It is concluded that with some limitations, this simple, noninvasive technique may be useful in identifying a source of bleeding in the workup of hematuria.

Evaluation of glomerular and nonglomerular hematuria by phase-contrast microscopy

Glomerular and nonglomerular origins of hematuria may be identified by assessment of the shape and size of the excreted red blood cells. We examined 380 urine specimens from 179 children with hematuria (greater than or equal to 3500 RBC/minute) with phase-contrast microscopy. In 106 cases, the cause was known; the results agreed with the clinical, histologic, and laboratory diagnosis in 63 of 65 subjects (97%) with glomerulopathies and in 39 of 41 (95%) with nonglomerular hematuria. Casts were found in 54% of the specimens from the children with definite glomerular hematuria. Phase-contrast microscopic examination of red blood cells in the urine is a simple, inexpensive, and noninvasive technique that permits an accurate distinction between glomerular and nonglomerular bleeding in pediatric patients.