The great majority of granulocytes in urinary sediment are neutrophils. The term leukocyturia or granulocyturia is generally used to indicate the presence of large numbers of these cells in the urine.


Granulocytes 'of compact appearance'. The morphology of the nucleus is unrecognizable
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They are usually rounded in shape, with a diameter of 14-16 micron In hypotonic urine they may, however, have a diameter of up to 30 micron, while in hypertonic urine they may be more or less the same size as red cells.
The most reliable method of identifying granulocytes is by studying the morphology of the nucleus, either under the

phase-contrast microscope or by staining; the 2% acetic acid test, which brings out the details of the nucleus, may also aid identification. It is not unusual to find eosinophils in the urine; moderately severe eosinophiluria, and concurrent elimination of neutrophils, can be observed in some cases of acute and chronic interstitial nephritis, cystitis (e.g. the cystitis in schistosomiasis) and in some transplant rejections.


Granulocytes with even more accentuaded swelling and degeneration
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Eosinophiluria can be detected by the Papanicolaou or the Wright-Giemsa stain as they stain selectively the eosinophil granules, which tend to mask the usually bilobed nucleus of these cells.