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Post-exposure prophylaxis (PEP)
Gonorrhea may be suspected based on symptoms or a medical examination.
Because symptoms are not always present, a person may be infected without knowing it. For this reason, regular screening for gonorrhea is recommended even is there are no symptoms.
A chlamydia infection often accompanies gonorrhea. People diagnosed with gonorrhea should be screened for chlamydial infection, and vice versa.
Doctors or other health care professionals usually use one or more laboratory techniques to diagnose gonorrhea. Routine procedures include the direct staining of the bacterium in samples of bodily fluids, as well as growing the bacteria in laboratory cultures. Many doctors prefer to use more than one test to increase the chance of an accurate diagnosis.
The Gram staining test (Gram stain) in the case of gonococcal urethritis involves preparing a smear of the discharge from the penis on a glass slide and staining the smear with a dye. The doctor or laboratory technician then uses a microscope to find the bacteria on the slide. Test results are usually available immediately. This test is quite accurate for men, but less so for women, and is not recommended for them.
The culture test involves placing a sample of the discharge on a culture plate (chocolate-coloured) and incubating it up for to two days to allow the bacteria to multiply. The sensitivity of this test depends on the site from which the sample is taken. Cultures of samples taken from the cervix detect the infection in about 90 percent of cases.
The doctor may also perform a culture test to detect infection at various sites. It is important to do a culture test when the person has symptoms, or when gonorrhea has been confirmed through another test to determine the bacteria’s resistance. In 2014, 6.7% of the strains found in culture tests showed resistance to azithromycin. Two bacteria resistant to cefixime (the drug most commonly used to treat gonorrhea) were discovered in 2015, and several strains are approaching this resistance. The culture test ensures that the infection will be completely eliminated.
Last revision by Dr. Judith Fafard, november 2016