top of page
woman looking for ibs test information.jpg

ibs-smart Blood Test

ibs-smart blood test

How does the ibs-smart test work?

ibs-smart measures the levels of two antibodies in your blood (anti-CdtB and anti-vinculin) known to be elevated in patients with post-infectious IBS (IBS-D or IBS-M). 


ibs-smart is the only licensed and patented antibody blood test for IBS.


What is the process of getting the ibs-smart test?

All that’s needed is a blood sample and a doctor’s signature. You can work with your own doctor or use work with a doctor online to obtain a test order form. 


Once that has been done, you will then be provided with a kit including a device to draw your blood at home. Once the blood has been drawn you will then send your sample to our lab.


Your results will be available, either by email or from your ordering doctor, within seven days after receiving your sample. 


If levels of either antibody are elevated in your blood, you can be diagnosed with IBS-D or IBS-M with up to 100% certainty. 

What does the test measure? 

ibs-smart measures the levels of two antibodies, anti-CdtB and anti-vinculin, that are known to be elevated in patients with post-infectious IBS.


Anti-CdtB is developed from an immune response to the toxin, CdtB, released by the most common bacteria that cause food poisoning. 


Anti-vinculin is an autoimmune response against a protein, vinculin, that is critical for healthy gut function. 


Elevated levels of either antibody indicate IBS.  


Which types of IBS does ibs-smart help diagnose?


ibs-smart is useful in the diagnosis of IBS-D and IBS-M. 


However, ibs-smart is not useful in the diagnosis of IBS-C, because the antibodies the test measures are not often found to be elevated in patients with IBS-C. 


How accurate is ibs-smart?

ibs-smart is the only licensed and patented antibody blood test for IBS and is a second-generation test for the measurement of anti-CdtB and anti-vinculin. (citation) 


ibs-smart has been scientifically validated and is performed in a CLIA-certified laboratory. 


Patients with elevated levels of either anti-CdtB or anti-vinculin, as measured by ibs-smart, can be diagnosed with IBS with 96% certainty (positive predictive value).


Patients with elevated levels of both anti-CdtB and anti-vinculin antibodies, as measured by ibs-smart, can be diagnosed with IBS with 100% certainty (positive predictive value). 


How do I know if ibs-smart is right for me? 

ibs-smart may be right for you if:


  • You have diarrheal IBS symptoms for four weeks or more, including stomach pain and cramping, bloating, diarrhea, and/or alternating diarrhea and constipation;


  • You have no major alarm symptoms (e.g., blood in your stool that has not yet been addressed by your healthcare provider); or


  • You would prefer a blood test before undergoing more complex or invasive procedures for your GI symptoms. 



If I don’t recall having food poisoning, should I still take the test? 

While ibs-smart measures antibodies that indicate IBS caused by food poisoning, it is not required that you recall any instances of food poisoning in the past. The instance of food poisoning may have been minor, and/or your IBS symptoms may have developed after a period of being asymptomatic


I have IBS-C (constipation). Can I use this test? 

Post-infectious IBS most commonly manifests as IBS with a diarrheal component (IBS-D or IBS-M). It very rarely manifests as constipation-predominant IBS (IBS-C). (Read more.)


It is recommended that ibs-smart be administered to those with symptoms of IBS-D or IBS-M and not to those with symptoms of IBS-C. 


While we generally don't recommend this test for constipation-predominant patients, there are some instances where these antibodies are elevated in patients with IBS-C. 


If the levels of anti-CdtB and/or anti-vinculin are elevated, an IBS diagnosis can still be made with 96% -100% certainty and the root cause can still be established as food poisoning. 


Does this test diagnose SIBO?

ibs-smart does not diagnose SIBO. ibs-smart measures the levels of two antibodies that indicate irritable bowel syndrome to a high degree of certainty. It is estimated that up to 80% of IBS patients have SIBO, so a positive result on ibs-smart indicates a high likelihood of SIBO, but does not provide a diagnosis of SIBO. 


SIBO is usually diagnosed with a breath test.


SIBO is associated with many illnesses in addition to IBS. A breath test can indicate SIBO but does not identify IBS as the associated illness, nor does it identify the root cause. 


Patients and prescribers might choose to use both the antibody blood test and a breath test to form a complete picture of the patient’s illness. 



I am currently on or have been on treatments for my condition (e.g., IGG therapy, antibiotics like Rifaximin). Will this impact the results of the test?


At this time, there is no definitive research to indicate the impact of specific treatments on the levels of anti-CdtB and anti-vinculin. Anecdotally, patients on various treatments have used ibs-smart and still received useful results. 

Type of IBS
Man Purple Shirt with no IBS pain.jpg

Get Answers
Get Well

bottom of page