The term leukocytes is indicated for the routine microscopy. The subclasses of leukocytes can be identified by staining with the Wright or PAP stain. Efficiency of these staining procedures is highly dependent of the conservation state of the cells. Staining with these represents a workload, not justified for the routine specimen. Neutros lysozomes havediverse enzyme activities, some being specific like the peroxydase.
Neutrophils also possess a heterogenic group of hydrolase gathered under the term esterase.
One of these esterases, the Naphtyl AS-D Chloroacetate esterase , seems to be specific for the polynuclear lineage. Since mastocytes are not seen in urine, and that the macrophage size and aspect is quite different from leukocytes, this activity is used in a specific staining procedure for leukocytes. Because of a pycnotic nucleus or of an unfavorable refractive index of the urine, the plurilobulated nucleus are not always obvious. In the urinary sediment, there are two types of neutrophils. When numerous, these cells are related to inflammation.