Culture of urethral discharge; Genital exudate culture; Culture - genital discharge or exudate
Urethral discharge culture is a laboratory test performed on males to isolate and identify organisms in the urethra and genital tract that cause infection.
How the test is performed
The opening of the urethra (at the tip of the penis) is cleansed with sterile gauze or cotton. A cotton swab is then gently inserted into the urethra about 3/4 inch and gently rotated. To ensure a good quality specimen, it should be collected at least 1 hour after urinating.
A culture of the discharge or exudate (the fluid that was collected) is then prepared in the laboratory. Any organisms that grow on the culture are isolated and identified. The drainage may be examined by Gram stain on a slide under the microscope for preliminary results and confirmed by culture.
How to prepare for the test
Do not urinate for 1 hour before the test. Urination will wash away some of the organisms needed to obtain an accurate culture.
Infants and children:
The preparation you can provide for this test depends on your child’s age, previous experiences, and level of trust. For general information regarding how you can prepare your child, see the following topics:
- Infant test or procedure preparation (birth to 1 year)
- Toddler test or procedure preparation (1 to 3 years)
- Preschooler test or procedure preparation (3 to 6 years)
- School age test or procedure preparation (6 to 12 years)
- Adolescent test or procedure preparation (12 to 18 years)
How the test will feel
There is usually some discomfort associated with swabbing the urethra.
Why the test is performed
Often the test is performed when there is a discharge from the urethra. This test can be performed to detect sexually transmitted diseases such as gonorrhea and chlamydia.
A negative culture, or no growth appearing in the culture, is normal.
What abnormal results mean
Abnormal results can indicate infection within the genital system. These infections can include gonorrhea or chlamydia.
What the risks are
Fainting (caused by stimulation of the vagal nerve) occasionally occurs when the swab is introduced into the urethra. Other risks include infection or bleeding.
A comparable test for females is an endocervical culture.
by Dave R. Roger, M.D.