The urethral swab is a diagnostic test aimed at finding microorganisms responsible for infections in the lower urinary tract. The test uses a simple and thin cotton bud, similar to a cotton bud, to be inserted through the urethral meatus (external orifice) for about 1 cm in the woman and 1-2 cm in the man. The swab is then gently turned over for a few seconds, in order to collect a certain amount of cells and exudate.
The material left in the urethral swab is subsequently analyzed in the laboratory, in order to identify the etiological agent and test its susceptibility to certain drugs. With the antibiogram, for example, the effect of various antibiotics on isolated bacterial species is evaluated. The choice of the most suitable antibiotic therefore allows the complete eradication of the microorganism, avoiding the appearance of dangerous antibiotic resistance.
The most common etiologic agent of lower urinary tract infections is the bacterium Neisseria gonorrhoeae (in these cases we speak of gonococcal or gonorrheal urethritis). In women, because of the lower anatomical length of the urethra, bladder infections (cystitis) are more frequent, while in humans urethritis is more often recorded.
In the male penis squeezing improves the sensitivity of the test, as it favors the ascent of any exudate along the urethra; sometimes rectal prostate stimulation may also be necessary. In women, the examination is generally painless, also due to the scarce penetration of the swab, while in humans it can cause several discomforts.
In order to obtain a sufficiently large number of samples on which to search for potential pathogens, generally five or six urethral swabs are performed.
Preparation for urethral swab
In order not to invalidate the outcome of the exam, it is good:
refrain from sexual intercourse in the 24 hours preceding it;
suspend all antibiotic and antifungal therapy in the week before;
avoid vaginal irrigations, local therapies in the vagina (eggs, glow plugs, etc.) and baths in the pool for 24 hours before the exam;
on the morning of the exam, take care of the external intimate hygiene with a little soap and water;
refrain from urinating in the previous three hours (the urethral swab is performed in the morning, before urination, in order to avoid the washing action of the urine on the walls of the urethra).
Failure to comply with these indications can produce false negatives, that is subjects who according to the results of the tampon are healthy when in reality they are sick.
When do you run?
The urethral swab is performed in the presence of suspicions on the presence of a genitourinary infection and to evaluate the efficacy of the therapy undertaken. Common symptoms of these conditions are frequent, painful and difficult urination (with a sense of incomplete emptying of the bladder), turbid yellow-greenish urine, sometimes smelly with traces of blood or pus, leakage of secretions from the penis and vaginal discharge. If these symptoms occur it is very important to promptly report them to the doctor, in order to eradicate the infection and prevent its often fearsome complications (extension of the infectious process to adjacent structures up to infertility).
The urethral swab, together with the vaginal / cervical one and sometimes the anal one, is also part of the prophylaxis and control tests during pregnancy.
