A piece of tissue from the first part of the small intestine is taken during an upper endoscopy (esophagogastroduodenoscopy, also called an EGD).

The sample is then sent to a lab. There it is placed in a special dish (culture media) that allows bacteria or viruses to grow. The sample is looked at under a microscope regularly to see if any organisms are growing.

Organisms that grow on the culture are identified.

This is a test done in a lab. The sample is collected during an EGD and biopsy procedure. Ask your health care provider how to prepare for this procedure.

A culture of duodenal tissue is done to check for bacteria or viruses that may lead to certain illnesses and conditions.

No harmful bacteria or viruses are found.

An abnormal finding means that harmful bacteria or a virus has been found in the tissue sample. Bacteria may include:

• Campylobacter
• Helicobacter pylori (H pylori)
• Salmonella

Risks of this test include:

• Bleeding
• Perforation of (poking a hole in) the gastrointestinal tract by the scope
• Infection

Some people may not be able to have this test because of other medical conditions.

Other tests are very often done to look for infection-causing organisms in duodenal tissue. These tests include the urease test (for example, the CLO test) and histology (looking at the tissue under a microscope).

Routine culture for H pylori is not currently recommended.

Duodenal tissue culture

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Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.