Red-cell-volume distribution curves in diagnosis of glomerular and non-glomerular haematuria.
The distribution curves of urinary red-blood-cell (RBC) size were obtained from automated blood-cell analysis in 146 patients with definite causes of haematuria. In 65 of 67 patients (97%) with haematuria and glomerulonephritis demonstrated by renal biopsy, urinary RBC had an irregular and asymmetrical distribution with RBC size showing a much smaller volume than that of venous RBC. This "glomerular" distribution contrasted with the "non-glomerular" normal distribution when the peak for RBC was at a larger volume than that for peripheral RBC. In 46 of 47 patients with haematuria who had lower urinary tract lesions other than infection, a non-glomerular distribution was obtained; 30 of these cases also showed glomerular distribution, and were classified as "mixed". All 32 patients with urinary tract infection had either a glomerular or mixed distribution, suggesting that they excreted distorted and dysmorphic urinary RBC. After excluding infections, this simple, rapid, reproducible, and non-invasive technique provides reliable information in distinguishing glomerular bleeding from other causes of haematuria.
D003937:Diagnosis, Differential; D004906:Erythrocyte Count / Q000379:methods; D004911:Erythrocyte Volume; D004913:Erythrocytes, Abnormal / Q000032:analysis*; D005921:Glomerulonephritis / Q000097:blood / Q000150:complications*; D006417:Hematuria / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008858:Microscopy, Phase-Contrast; D014552:Urinary Tract Infections / Q000097:blood / Q000150:complications