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Evaluation of the results of a glass sample
Last reviewed: 23.04.2024
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When conducting a glass sample, 2 or 3 portions of urine, obtained sequentially with a single urination, are examined. Prior to the sample, the patient should not urinate for 3-5 hours. With a two-glassed sample, the patient collects urine in 2 vessels: in the first one there should be 100 ml of urine, in the second there should be 100 ml of urine, in the second - the remaining volume. With a three-glassed sample, urine is collected in 3 vessels: in the first - the initial portion, in the second - the average, in the third - the final one.
Glass samples are widely used in urological practice, especially in men. They provide substantial assistance in establishing the localization of the pathological process. The presence of pathological impurities (leukocytes, erythrocytes) only in the first portion indicates that their source in the urethra (urethritis, urethral damage, tumor). Pathological impurities are found in approximately the same amount in all the portions of urine when the process is localized in the kidney or ureter, as well as in the bladder, if they enter the urine from the lesion permanently (for example, with a bleeding bladder tumor). If the white blood cells, pus, mucus or blood (erythrocytes) are found only in the last portion of the urine, there is reason to suppose the localization of the focus in the bladder or in the prostate gland.
A three-glassed sample is sometimes supplemented with a massage of the prostate gland and seminal vesicles. The patient urinates in the first two vessels, leaving a part of the urine in the bladder. After that, massage the prostate gland, and the patient fills the 3-rd vessel with urine. Changes in the last portion of urine (after massage of the prostate gland or seminal vesicles) indicate an inflammatory process in these organs.
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