Small bowel tissue smear/biopsy
Small bowel tissue smear is a lab test that checks for disease in a sample of tissue from the small intestine.
A sample of tissue from the small intestine is removed during a procedure called esophagogastroduodenoscopy (EGD). A brushing of the intestine lining can also be taken.
The sample is sent to a laboratory. There it is sliced, stained, and placed on a microscope slide to be examined.
How to Prepare for the Test
You will need to have an EGD procedure for the sample to be taken. Prepare for this procedure in the way your health care provider recommends.
How the Test will Feel
You are not involved in the test once the sample is taken.
Why the Test is Performed
Your provider may order this test to look for an infection or other disease of the small intestine. In most cases, this test is done only when a diagnosis could not be made using stool and blood tests.
A normal result means that there were no indicators of disease when the sample was examined under the microscope.
The small intestine normally contains certain healthy bacteria and yeast. Their presence is not a sign of disease.
Normal value ranges may vary slightly among different laboratories. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
An abnormal result means that certain microorganisms, such as the parasites giardia or strongyloides were seen in the tissue sample. It may also mean that there were changes in the structure (anatomy) of the tissue.
The biopsy may also reveal evidence of celiac disease, Whipple disease or Crohn disease.
There are no risks associated with a laboratory culture.
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