What Causes IBS?

What Causes IBS?

In North America, about 1 in 10 people suffer from chronic abdominal pain, bloating, diarrhea or constipation but have normal test results. These people fall under the diagnosis of irritable bowel syndrome (IBS), but there is no good explanation of the cause of their suffering.   For a while, the medical world was quite puzzled about what to do for IBS.  Doctors searched for those problematic bugs in the stools but couldn’t find any. However, when they treated patients with antibiotics, some would get better.  

Unfortunately, treating IBS with antibiotics is like blindly throwing darts on a board and hoping some will hit the target. The results have been inconsistent and don’t last.  Doctors have also noted that this disorder is more commonly seen in anxious women, so it probably has something to do with anxiety.  

The Causes of IBS 

In the last few years, a new theory has emerged and offered some insight into this puzzling disorder. Dr. Pimentel, from the Medically Associated Science and Technology Program at Cedars-Sinai, is one of the top gastroenterologists and researchers in the field of IBS.  He and his team have discovered that about 60-70% of IBS-D, IBS with diarrhea rather than constipation, is a result of a past food poisoning.  His research shows that some common bad bugs that cause food poisoning produce Cytolethal Distending Toxin B (CdtB).  This toxin is what causes us to have multiple trips to the bathroom with abdominal pain, vomiting and diarrhea.  Our body’s immune system recognizes this toxin and decides to take action. It starts to make antibodies against this toxin, but unfortunately, this toxin has a similar structure to a protein in our small intestine, the migrating motor complex (MMC).  Our immune system sometimes gets confused with the resemblance, mistakenly thinking this protein is the bad guy and making antibodies (Anti-vinculin) against it too.  Anti-vinculin attacks the MMC in the small intestine, and the damaged MMC gives the bacteria an opportunity to accumulate in the small intestine. This overgrowth of bacteria will eventually cause the abdominal pain, bloating and diarrhea associated with IBS.  

Managing IBS 

People with elevated anti-vinculin in their system will have chronic IBS, because it is an autoimmune disease at this point.  It will be common to see symptoms relapse, but it doesn’t mean that suffering is ongoing.  With the correct management, people can have their symptoms minimized and still have a quality of life.   Please seek out trained medical professionals to evaluate and manage your symptoms if you suspect that you have IBS.