The term leukocyturia refers to the presence of leukocytes or immune system cells in the urine, in particular of neutrophil granulocytes with non-specific action. The causes of their presence in the urine, measured by the quantification of leukocyte esterase or neutrophil elastase, may be attributable to infectious processes or persistent chronic inflammation, even in the absence of overt bacterial infections or viral infections. However, leukocyturia can also occur due to other causes such as a blockage or obstruction (by stones or prostatic hypertrophy) of the urinary tract, after sexual intercourse, when one is forced to retain urine for a long time or in pregnant women. Leukocyturia can be asymptomatic, especially if it is not caused by pathogens or it can give the same symptoms of bacterial cystitis. In both cases, it is good not to underestimate the phenomenon and intervene with the most appropriate therapy. Even in the absence of a pathogenic agent, inflammation and the presence of leukocytes in the urine can remain for long periods of time, which contributes to the maintenance of urinary incontinence and bladder burning. D-mannose and other glycosaminoglycans (dermatan sulfate, sodium hyaluronate, keratan sulfate, glucosamine sulfate and methylsulfonylmethane) usually contribute to the formation of a lining of the bladder which gives the urothelium and bladder the correct protection, fundamental in these cases of bladder hypersensitivity.