Definition of Gram stain of urethral discharge:

A gram stain of urethral discharge is a test used to identify bacteria in fluid from the tube that drains urine from the bladder (urethra).

How the test is performed:

Fluid from the urethra is collected on a cotton swab. A sample from this swab is applied in a very thin layer to a microscope slide. A series of stains called a gram stain is applied to the specimen.

The stained smear is then examined under the microscope for the presence of bacteria. The color, size, and shape of the cells help identify the organism causing the infection.

How to prepare for the test:

This test is often performed in the health care provider's office.

How the test will feel:

You may feel pressure or burning when the cotton swab touches the urethra.

Why the test is performed:

The test is performed when an abnormal urethral discharge is present. It may be performed if a sexually transmitted disease is suspected.

Normal Values:

No presence of organisms is normal.

What abnormal results mean:

Abnormal results may indicate gonorrhea or other infections.

What the risks are:

There are no risks.

Special considerations:

A culture of the specimen (urethral discharge culture) should be performed in addition to the gram stain. More sophisticated diagnostic tests (such as PCR tests) are sometimes also done.