Small bowel tissue smear is a laboratory test that checks for disease in a sample of tissue from the small intestine.
How the test is performed
A sample of tissue from the small intestine is removed during a procedure called esophagogastroduodenoscopy (EGD). For more information on this procedure, see EGD.
The sample is sent to a laboratory, where it is sliced, stained, and placed on a microscope slide for examination.
How to prepare for the test
For information on how to prepare for the removal of tissue from your small intestine, see EGD.
How the test will feel
For information on how it will feel to have a sample of intestinal tissue removed, see EGD.
Why the test is performed
Your health care provider may order this test if you have signs or symptoms of an infection or other disease of the small intestine. In most cases, this test is only done when a diagnosis was not able to be made from stool and blood tests.
A normal result means no disease-related substances or changes were found in the sample when 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 health care 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, or that there were changes in the structure (anatomy) of the tissue.
What the risks are
A laboratory smear poses no risks to the patient. For risks related to obtaining a sample of intestinal tissue, see EGD.
Examination of tissue by a pathologist can help in the diagnosis of certain intestinal infections.
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Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington; and 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. Health Solutions, Ebix, Inc.