Rectal culture is a laboratory test to identify bacteria and other germs in the rectum that can cause gastrointestinal symptoms and disease.
Culture - rectal
A cotton swab is inserted into the rectum. The swab is rotated gently, and removed.
A smear of the swab is placed in culture media to encourage 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 health care provider suspects that you have an infection of the rectum, such as gonorrhea. It may also be done instead of 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. This organism can be spread to other patients.
Finding bacteria and other germs that are commonly found in the body is normal.
Normal value ranges may vary slightly among different laboratories. Talk to your health care provider about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results may mean you have an infection. This may be from bacterial or parasitic enterocolitis or gonorrhea. Sometimes a culture shows that you are a carrier, but you may not have an infection.
A related condition is proctitis.
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.
DuPont HL. Approach to the patient with suspected enteric infection. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 291.
Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 142.
Giannella RA. Infectious enteritis and proctocolitis and bacterial food poisoning. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, PA: Saunders Elsevier; 2010:chap 107.
Croft AC, Woods GL. Specimen collection and handling for diagnosis of infectious diseases. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 63.
Salwen MJ, Siddiqi HA, Gress FG, Bowne WB. Laboratory diagnosis of gastrointestinal and pancreatic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 22.
Reviewed By: Jenifer K. Lehrer, MD, Department of Gastroenterology, Frankford-Torresdale Hospital, Aria Health System, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.