ASIBObreath test can reveal if your chronic intestinal symptoms are caused bysmall intestinal bacterial overgrowth(SIBO).
Research suggests SIBO is underdiagnosed.
Who Should Be Tested?
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SIBO Breath Test
Breath testing is non-invasive.
It’s used fairly frequently as a way to look for SIBO.
When bacteria in the small intestine interact with sugar, they release hydrogen or methane.
Those chemicals then come out in your breath.
For the test, you consume a sugary drink and then have your breath checked periodically.
If hydrogen is detected before the 90-minute mark, it suggests SIBO.
Bacteria that produce hydrogen belong in the large intestine, not the small one.
It takes about two hours for the sugar to reach the large intestine.
That’s why the cutoff is 90 minutes.
The breath test is currently the primary diagnostic tool for SIBO.
There are two types of breath tests: One uses glucose and the other lactulose.
Of the two, the glucose test seems to be better.
But both are often inaccurate.
The sensitivity and specificity of the tests range from 42% to 83%.
The test can also produce false negatives.
That’s often because ofgastroparesis(slow emptying of the stomach).
At one time, there was no agreement about how best to perform the tests.
There is emerging research for breath tests that measure hydrogen and methane that may provide greater accuracy for diagnosis.
Your healthcare provider or the facility will tell you how to prepare.
During the Test
During the test, you may be asked to rinse your mouth with mouthwash.
That kills any bacteria that may be present.
You’ll then give a baseline breath sample.
Usually, that means blowing up a balloon.
Then you’ll drink a small amount of sugary liquid.
Every 15 minutes, you’ll give them another breath sample.
The test will last two to three hours, depending on the jot down of sugar used.
Jejunal Aspiration
A more accurate testbut also more invasiveisjejunalaspiration.It takes place during an upperendoscopyprocedure.
An upper endoscopy involves a long tube with a camera threaded down through your mouth and throat.
It’s named for the middle section of your small intestine: the jejunum.
During the endoscopy, the practitioner can take a sample.
It’s then cultured and evaluated for bacteria.
Jejunal aspiration isn’t used often.
It’s costly, time-consuming, and carries more risk than a breath testalthough it’s generally considered safe.
Jejunal aspiration has limits to its accuracy for SIBO.
Your healthcare provider or the testing center will tell you how to prepare.
Those instructions will likely be similar to those for the breath test.
The test will take place either at your healthcare provider’s office or at a testing facility.
An IV will most likely be started.
You’ll get a mild sedative to relax you.
It may not put you fully out.
Next, a numbing anesthetic will be sprayed on your throat.
Then a thin tube will be inserted down your throat.
You’ll be able to breathe but not talk.
Your healthcare provider will then take a sample of fluid from your small intestine using an aspiration catheter.
Then the tube will be removed from your throat.
After that, you may rest for a while to allow the anesthesia to wear off.
Because you’ll be sedated, you’ve got the option to’t drive yourself home afterward.
For the rest of the day, keep your activity to a minimum.
Medication Trial
One way to check for SIBO is with a trial of SIBO medication.
If symptoms quickly drop off, it suggests you have it.
The most common SIBO drug is Xifaxan (rifaximin)an antibiotic.It’s different from most antibiotics, though.
Rather than being absorbed into your bloodstream, it acts directly on bacteria in your small intestine.
The medical community hasn’t yet set dosing standards for SIBO trials.
But some healthcare providers follow the FDA guidelines for using Xifaxan to treatdiarrhea-predominant IBS(IBS-D).
This approach has limits, though.
So this approach is a tricky one to gauge.
Summary
SIBO may be underdiagnosed.
If you have ongoing bowel problems, you should be tested.
Three types of SIBO testing are used:
Each approach has pros and cons for diagnosing SIBO.
Salem A, Roland BC.Small intestinal bacterial overgrowth (SIBO).J Gastroint Dig Syst.
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doi:10.14309/ctg.0000000000000072
U.S. Food and Drug Administration.FDA approved drugs: Xifaxan: labeling/package insert.
