[Evaluation of a new method for diagnosing the origin of urinary bleeding by the morphological characteristics of urinary red blood cells].

In this study, we attempted to develop a new method for diagnosing the origin of urinary bleeding by the morphological characteristics of urinary red blood cells (RBC). Seventy-five samples were divided into five types by individual features using phase-contrast microscopy. It was revealed that the ratios of type III, namely acanthocytes, and IV, namely donut-shaped RBC, were significantly higher in patients with glomerular bleeding than those with non-glomerular bleeding. Acanthocytes seemed to be specific to glomerular bleeding, but some urinary samples from patients with glomerular bleeding did not show acanthocytes. Therefore, we suggest that the detection of a combination of acanthocytes and donut-shaped RBC in a urine sample is useful for the diagnosis of glomerular bleeding.