Smear of duodenal fluid aspirate is an exam of fluid from the duodenum to check for signs of an infection (such as giardia or strongyloides). Rarely, this test is also done in a newborn to check for biliary atresia.
How the Test is Performed
A sample is taken during a procedure called an esophagogastroduodenoscopy (EGD).
How to Prepare for the Test
Do not eat or drink anything for 12 hours before the test.
How the Test will Feel
You may feel like you have to gag as the tube is passed, but the procedure is most often not painful. You can get medicines to help you relax and be free of pain. If you get anesthesia, you cannot drive for the rest of the day.
Why the Test is Performed
The test is done to look for infection of the small bowel. However, it is not often needed. In most cases, this test is only done when a diagnosis cannot be made with other tests.
There should be no disease-causing organisms in the duodenum. 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
The results may show the presence of giardia protozoa, the intestinal parasite strongyloides, or another infectious organism.
The risks of this test include:
- Perforation of (poking a hole in) the gastrointestinal tract by the scope
Some people may not be able to have this test because of other medical conditions.
Other tests that are less invasive can often find the source of the infection.
Duodenal aspirated fluid smear
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Review Date 4/7/2020
Updated by: Michael M. Phillips, MD, Clinical Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.