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 is the Test 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.

Preparation for the Test

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

How will the Test Feel?

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

Why is the Test Performed?

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

Normal Results for Gram stain of urethral discharge

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

Abnormal results may indicate gonorrhea or other infections.

Gram stain of urethral discharge Risks

There are no risks.

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.

References

McCormack WM. Urethritis. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 106.

Cohen MS. Approach to the patient with a sexually transmitted disease. In: Goldman L, Ausiello D, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 293.

Related Images

Review Date: 8/12/2011
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2014 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
Hide
(web1)