Leukocyturia

Leukocyturia describes the presence of leucocytes in the urine.

Under physiological conditions, leukocytes are excreted in the urine. It is assumed that in daily urine, the number of expelled leukocytes should be less than 2,000,000. A number greater than 2 million is called leucocyturia and can be determined when determining the Addis count.^[1]

However, the above mentioned method requires a 24-hour urine collection, so it is not practical. Currently, the number of leukocytes is estimated under the microscope for which morning urine is taken. It has been arbitrarily assumed that a number of over 4 - 5 leukocytes in the field of vision of the microscope indicates leukocyturia.^[2]

At the moment, there are also quick test strips available, allowing after wetting a special diagnostic bar, the detection of granulocytes in the urine, as evidenced by the color change of the test strip.^[3] The principle of their operation is based on the detection of granulocytes esterases , including leukocytes. This method, however, is burdened with a large number of false positive results (use of antibiotics, such as imipenem, meropenem, clavulanic acid, which is sometimes combined with penicillin derivatives) or false negative (gentamicin, cefalexin, glycosuria, proteinuria).

Leukocyturia is a laboratory symptom of many diseases like glomerulonephritis or pyelonephritis. It may occur in the case of diseases of the urinary tract, reproductive system and diseases of the abdominal organs.^[4] Leukocyturia is mostly a sign of urinary tract infection, especially if significant bacteriuria is found (for most people, the number of bacteria in a culture is > 10^5) and other symptoms associated with passing urine.^[5] The presence of leukocyturia does not indicate the need for antimicrobial therapy yet.

Leukocyturia, accompanied by a discoloration, clouding or change in the smell of urine, is called pyuria.

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