Tests used to diagnose gonorrhea include staining samples for the bacterium, detecting bacterial genes or DNA in urine, and growing the bacteria in laboratory cultures. The staining test generally works better in men than women, and the gene test is more accurate than growing cultures. Regardless of the method used to diagnose gonorrhea, prompt treatment is the key to overcoming this disease.
Several laboratory tests are available to diagnose gonorrhea. These tests can include:
- Staining samples directly for the bacterium
- Detecting bacterial genes or DNA in urine
- Growing the bacteria in laboratory cultures.
A quick laboratory test for gonorrhea that can be done in some clinics or doctors' offices is a Gram stain. A Gram stain of a sample from a urethra or a cervix allows the doctor to see the gonorrhea bacterium under a microscope. This test tend to work better for men than for women.
In most cases, healthcare providers will use urine or cervical swabs for a new test that detects the genes of the bacteria. These tests are more accurate than culturing the bacteria.
The laboratory culture test involves placing a sample of the discharge onto a culture plate and incubating it for up to 2 days to allow the bacteria to grow. The sensitivity of this test will depend on the site from which the sample is taken. Cultures of cervical samples detect infection approximately 90 percent of the time. The healthcare provider also can take a culture to detect gonorrhea in the throat and to test for drug-resistant bacteria.