Pyuria, or pus in urine, is a medical condition defined as the passing of significant amounts of white blood cells in urine. Pyuria translates as pus in the urine, which really means there is a higher than expected concentration of white blood cells in a dog’s urine.
While most cases of pyuria are due to a true urinary tract infection, some cases are observed in dogs without an infection. This happens when there is physical damage to the urinary tract, as is the case when kidney stones are passed. The white blood cells are a result of inflammation, not infection.
A significant amount of white blood cells in the voided urine sample indicate inflammation somewhere in the urogenital tract. A number of medical problems can be associated with this condition ranging in severity and causing cellular injury, tissue damage, inflammation or death; tissue damage can provoke oozing inflammation, characterized by evidence of pyuria and increased red blood cells and protein in the urine.
Besides pustulant discharge, other symptoms are as follows:
Local Effects of Inflammation
Redness of mucosal surfaces (e.g., redness of vaginal or prepuce mucous tissue)
Pain (e.g., adverse response to touch, painful urination, frequency of urination)
Loss of function (e.g., excessive urination, painful urination, frequent urination, urinary incontinence)
Systemic Effects of Inflammation
Loss of appetite (anorexia)