The test according to Meares and Stamey (Stamey TA. Prostatitis. J R Soc Med. 1981; 74 (1): 22-40) is considered the gold standard among the diagnostic methods for the detection of prostatitis.

It is a diagnostic procedure that is carried out by means of a fractionation of the lower urinary tract, that is, by collecting 3 samples of the patient's urine in different conditions.

These samples are called VB1, VB2 and VB3. The term VB stands for "Voided Bladder"

VB1

Sample VB1 consists of the first 10 milliliters of urine collected in the morning. This first urinary output can collect any microorganisms present in the urethra, and can therefore represent an index of infection at that level.

VB2

The VB2 sample is collected after the VB1 and represents the so-called "intermediate mitto". In this case, the sample can collect microorganisms present in the bladder (it is assumed that the first discharge urine (VB1) has completely or partially removed any urethral material). The positivity of the VB2 sample can therefore indicate the presence of pathogens in the bladder.

After collecting the VB2 sample, the urologist proceeds to perform a prostate massage on the patient under examination. The massage is performed by exerting light pressure on the prostate, moving from the lateral margins to the central-apical portion of the gland. The procedure can take about a minute. During the prostate massage, a few drops of prostatic secretions may come out, which are collected to be subjected to microbiological analysis and culture, together with samples VB1, VB2 and VB3.

VB3

The VB3 sample is collected at the end of the prostate massage. Urine VB3, exerting a washing of the urethra, can collect additional prostate material (represented in orange, in the context of blue urine). In case of non-collection of prostatic secretion, the VB3 may represent the only sample containing bacteria located in the prostate.

Positivity of the EPS (prostatic secretion) and / or VB3 samples, in case of negative cultures of the other samples, indicates a possible infection in the prostate gland.

If the VB1 and / or VB2 samples are positive, an indication of prostatitis can be had if the bacterial load in the VB3 sample is at least ten times that measured in the first or intermediate samples.