Round cells in urinary samples from healthy donors

Abstract

Round cells are a new type of renal tubular epithelial cell. The current Japanese “Examination of Urinary Sediment 2010” does not mention round cells, which were observed in this study. In our previous study, we found round cells in urinary samples collected from patients with end-stage renal disease, and their number was found to correlate with the severity of chronic kidney disease. However, their existence in samples from healthy donors has not been reported. The purpose of this study is to examine urinary samples for round cells in urinary sediment. Urinary samples were collected from 78 healthy donors. Urinary sediment was examined by a standard method in accordance with the 2010 GP1-P4 guideline. Round cells were counted in whole fields (WFs) under 100× magnification, and microscopy images were captured. Cell size was determined using Image J. In this study, we detected round cells in samples from healthy donors.The cytoplasm was of the homogeneous or granular-vacuum type. The average size of round cells was 15.38 ± 1.84 μm. The viability rate of cells with the homogeneous-type cytoplasm was higher than that of cells with the granular-vacuum-type cytoplasm. This study confirmed that living round cells can be detected in samples from healthy donors.