Page Contents
OVERVIEW
This guide is dedicated to helping establish a framework for working up a patient who complains of symptoms suggestive of urethritis. These include:
- Dysuria (which can also be described as burning during urination)
- Urethra discharge that can be watery to frankly purulent. It can be scant in presentation (and sometimes only is present on the first morning void)
- Penile/vaginal pruritus is a common presentation as well.
Urethritis is very suggestive of some type of sexually transmitted infection (that will be elaborated more below.
*It is important to appreciate that some patients will be asymptomatic even thought the possess an infective cause of urethritis.
INTIIAL CLASSIFICATION: GONOCOCCAL VS. NONGONOCOCCAL
While urethral swabs are not as common as they once were, it is important to understand how they can be a very quick way to characterize the type of urethritis a patient may possess (as either gonococcal or nongonococcal (each with its own individual diagnostic path). This procedure is exactly as it sounds. A swab is used to capture the infectious organism in urethra, and is then gram stained/stained with methylene blue for visualization under light microscopy. This can be done quickly at the initial clinic visit so that following treatments and diagnostic evaluations can be tailored to 1 of 2 paths! This will save time and money!
Gonococcal urethritis: the utility of the urethral swab is that if the cause of the patients symptoms is a gonococcal infection, this can be visualized very quickly under the microscope. Intracellular/extracellular diplococci will be present in the urethral exudate (either gram negative or dark purple depending on stain used). From this point on the diagnostic path is much less vast.
![Gram stain of penile exudate showing gram negative diplococci suggestive of gonococcal urethritis (source)](http://www.stepwards.com/wp-content/uploads/2016/06/gram-stained-urethral-exudate-sample-from-a-male-who-presented-with-a-case-of-urethritis-725x483.jpg)
Nongonococcal urethritis (NGU): if the gram stain only shows white blood cells and no pathogens that can be visualized with a gram stain, then a different diagnostic path must be taken.
![Gram stain of urethral discharge showing only white blood cells. This is suggestive of a nongonococccal urethritis (source)](http://www.stepwards.com/wp-content/uploads/2016/06/2740e0cd990e80e2acff682788e656b3.jpg)
CHARACTERIZING/TREATING GONOCOCCAL URETHRITIS
If microscopy demonstrates gonococcal urethritis, then almost certainly the cause of the patients symptoms is the bacteria Neisseria gonorrhoeae.
Confirmatory testing can invovle a nucleic acid amplification test (NAAT) for Neisseria gonorrhoeae on first voided urine however the gram stain results are likely enough to begin treatment.
Treatment involves a single intramuscular dose of ceftriaxone (250 mg) and a single dose of azithromycin (1 gram). This treatment also covers chlamydia.
CAUSES OF NONGONOCOCCAL URETHRITIS
If microscopy does not demonstrate gonococcal urethritis. Then the causal pathogen/process must be identified. The likely candidates include:
- Chlamydia trachomatis is the most likely and often empirically treated.
- Mycoplasma genitalium
- Ureaplasma urealyticum
- Trichomonas vaginalis
- Treponema pallidum
- Herpes simplex virus can be the cause of urethritis (however generally a clinical exam will reveal signs of genital herpes).
- Other unspecified pathogens might also be the cause of a patients urethritis (if all of the above have been ruled out). Many cases do not have a clear etiology. They have been associated with men who have sex with men and bacterial vaginosis (source)
Non STI causes of dysuria: should all of the pathogens/processes above be ruled out it is important to appreciate that the below infective processes might also present with dysuria.
- Cystitis
- Epididymitis
- Prostatitis
Noninfectious causes of urethritis: should all of the pathogens/processes above be ruled out, noninfectious causes of the patients symptoms should be explored:
- Chemical irritation: spermicides and soaps
- Stripping of urethra by the patient (trauma)
DIAGNOSING CAUSE OF NONGONOCOCCAL URETHRITIS
Generally the assumption is that NGU is caused by Chlamydia trachomatis and the patient s
NONINFECTIOUS CAUSES OF URETHRITIS
FURTHER READING
Page Updated: 06.07.2016