Rectal culture is a lab test to identify bacteria and other germs in the rectum that can cause gastrointestinal symptoms and disease.
How the Test is Performed
A cotton swab is placed into the rectum. The swab is rotated gently and removed.
A smear of the swab is placed in culture media to allow the growth of bacteria and other organisms. The culture is watched for growth.
The organisms can be identified when growth is seen. More tests may be done to determine the best treatment.
How to Prepare for the Test
The health care provider does a rectal exam and collects the specimen.
How the Test will Feel
There may be pressure as the swab is inserted into the rectum. The test is not painful in most cases.
Why the Test is Performed
The test is done if your provider suspects that you have an infection of the rectum, such as gonorrhea or chlamydia. It may also be done instead of a fecal culture if it is not possible to get a specimen of feces. Nucleic acid amplification testing (NAAT) is preferred for gonorrhea and chlamydia.
The rectal culture may also be performed in a hospital or nursing home setting. This test shows if someone carries vancomycin-resistant enterococcus (VRE) in their intestine. This germ can be spread to other patients.
Normal Results
Finding bacteria and other germs that are commonly found in the body is normal.
Normal value ranges may vary slightly among different labs. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results may mean you have an infection. This may include:
- Bacterial infection
- Parasitic enterocolitis
- Gonorrhea
Sometimes a culture shows that you are a carrier, but you may not have an infection.
A related condition is proctitis.
Risks
There are no risks.
Alternative Names
Culture - rectal
Images
References
Axelrad JE, Melia JMP. Infectious enteritis and proctocolitis. In: Chung RT, Rubin DT, Wilcox CM, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 12th ed. Philadelphia, PA: Elsevier; 2026:chap 112.
Edwards JL, Marrazzo JM. Neisseria gonorrhoeae (Gonorrhea). In: Blaser MJ, Cohen JI, Holland SM, et al, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 10th ed. Philadelphia, PA: Elsevier; 2026:chap 217.
Fleckenstein JM. Approach to the patient with suspected enteric infection. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 262.
Tan M, Jordan SJ. Chlamydia trachomatis (urogenital infections and Trachoma). In: Blaser MJ, Cohen JI, Holland SM, et al, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 10th ed. Philadelphia, PA: Elsevier; 2026:chap 186.
Review Date 4/27/2026
Updated by: Todd Eisner, MD, Private practice specializing in Gastroenterology in Boca Raton and Delray Beach, Florida at Gastroenterology Consultants of Boca Raton. Affiliate Assistant Professor, Florida Atlantic University School of Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.