Urethral discharge culture is a laboratory test done on men and boys to identify organisms in the urethra (the tube that drains urine from the bladder) and genital tract that cause infection.

Often the test is performed when there is a discharge from the urethra. This test can detect sexually transmitted diseases, such as gonorrhea and chlamydia.

The health care provider cleans the opening of the urethra (at the tip of the penis) with sterile gauze or cotton. To collect the sample, a cotton swab is then gently inserted about 3/4 inch into the urethra and rotated. To get a good sample, the test should be done at least 1 hour after urinating.

The sample is sent to a laboratory where it is placed in a special dish (culture) and watched to see if bacteria or any other organisms grow. The laboratory technician isolates and identifies any organisms that grow on the culture. The drainage may be examined on a slide under the microscope and then confirmed by culture.

Do not urinate for 1 hour before the test. Urination will wash away some of the organisms needed to obtain an accurate culture.

There is usually some discomfort from swabbing the urethra.