Rectal culture is a laboratory test to identify organisms in the rectum that can cause gastrointestinal symptoms and disease.
Culture - rectal
How the test is performed
A cotton swab is inserted into the rectum, rotated gently, and removed. A smear of the swab is placed in culture media to encourage the growth of bacteria and other organisms. The laboratory technician watches the culture for growth.
When growth is observed, the organisms can be identified. Further tests to determine the best treatment may also be done.
See also: Sensitivity analysis
How to prepare for the test
The health care provider does the rectal examination and collects the specimen.
How the test will feel
There may be pressure as the swab is inserted into the rectum, but the test is usually not painful.
Why the test is performed
The test is performed if you have gastrointestinal distress and your doctor suspects that an infection of the rectum is the cause. It may be done when gonorrhea is suspected. It may also be done as an alternative to a fecal culture if it is not possible to get a specimen of feces.
The rectal culture may also be performed in a hospital or nursing home setting to see if someone carries vancomycin-resistant enterococcus (VRE) in their intestine, which can be spread to other patients.
Finding organisms that are usually found in the body is normal and does not indicate disease.
Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean
Abnormal results may indicate an infection, such as bacterial or parasitic enterocolitis or gonorrhea. Sometimes a culture shows that the patient is a carrier, but does not necessarily have an infection.
See also: Proctitis
What the risks are
There are no risks.
Stamm WE, Batteiger BE. Chlamydia trachomatis (trachoma, perinatal infections, lymphogranuloma venereum, and other genital infections). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 180.
Marrazzo JM, Handsfield HH, Sparling PF. Neisseria gonorrhoeae. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 212.
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.