What's the Difference Between Celiac Disease and Ileitis, Colitis, Crohn's Disease and Irritable Bowel Syndrome?

As the spouse of someone who was diagnosed with celiac disease more than 35 years ago, I will admit that becoming more educated about the subject is a continuing process. This educational process has, at times, caused confusion for me.

One area that has caused confusion is understanding the difference between celiac disease and other diseases and conditions that also affect the gastrointestinal tract. Are these diseases and conditions similar to celiac disease, and are they related? These other diseases and conditions are: ileitis, colitis, Crohn’s disease, and irritable bowel syndrome.

To learn more about these, I searched for the websites of any national groups, organizations, or foundations for these diseases. As mentioned in a previous blog, I am not a medical practitioner of any kind, so if you have questions or need specific information on any of these diseases and conditions, please consult your physician.

As you already know, celiac disease is an autoimmune disorder caused by an intolerance to the gluten found in wheat, barley, and rye. I’m assuming you are also aware of and have already visited the website for the Celiac Disease Foundation. If not, you should. It contains a wealth of information about living with celiac disease.

As it turns out, there is also a national foundation for both Crohn’s disease and colitis called the Crohn’s & Colitis Foundation of America (CCFA). There is also a wealth of information on this site, but I’m only including the information that helped me better understand these diseases and clear up any confusion on my part. I highly recommend you go to the site and read all the information provided.

About Crohn’s disease, it says: “Crohn’s disease belongs to a group of conditions known as Inflammatory Bowel Diseases (IBD). Crohn’s disease is a chronic inflammatory condition of the gastrointestinal tract... It is important to know that Crohn’s disease is not the same thing as ulcerative colitis, another type of IBD. The symptoms of these two illnesses are quite similar, but the areas affected in the gastrointestinal tract (GI tract) are different. Crohn’s most commonly affects the end of the small bowel (the ileum) and the beginning of the colon, but it may affect any part of the gastrointestinal (GI) tract, from the mouth to the anus...Ulcerative colitis is limited to the colon, also called the large intestine.”
About colitis, also known as ulcerative colitis, it says: “Ulcerative colitis is a chronic disease of the large intestine, also known as the colon, in which the lining of the colon becomes inflamed and develops tiny open sores, or ulcers.”

In addition, the CCFA site says: “While both ulcerative colitis and Crohn’s disease are types of Inflammatory Bowel Diseases (IBD), they should not be confused with Irritable Bowel Syndrome (IBS), a disorder that affects the muscle contractions of the colon. IBS is not characterized by intestinal inflammation.”

I then decided to search for the term “’irritable bowel syndrome” on Google. I found no national foundation or website, but there was some interesting information on a National Institutes of Health website called National Digestive Diseases Information Clearing House. It helped clarify several misconceptions I had. It says: ”Irritable bowel syndrome is a functional gastrointestinal (GI) disorder, meaning symptoms are caused by changes in how the GI tract works. People with a functional GI disorder have frequent symptoms; however, the GI tract does not become damaged. IBS is a group of symptoms that occur together, not a disease. In the past, IBS was called colitis, mucous colitis, spastic colon, nervous colon, and spastic bowel. The name was changed to reflect the understanding that the disorder has both physical and mental causes and is not a product of a person’s imagination.”

Further, since I didn’t see any information on the CCFA site about ileitis, I also searched for that term on Google. I couldn’t find a national foundation or website specifically for ileitis, but did learn that ileitis refers to inflammation of the ileum, or small intestine, as described on the CCFA site, and can be caused by Crohn’s Disease affecting the ileum. Another National Institutes of Health website says there can also be ileitis not caused by Crohn’s disease but by a variety of other diseases. Please refer to this website for information on those types of ileitis.

By now you may be asking what any of this has to do with celiac disease, or why I was confused in the first place. Since reading more information about ileitis, colitis, and irritable bowel syndrome, I have learned that:

- Except for irritable bowel syndrome (IBS), the other diseases and conditions I was wondering about all involve inflammation in the GI tract, including celiac disease.

- IBS should not be confused with irritable bowel disease (IBD). The two are different. IBS involves muscle contraction while IBD involves inflammation.

- Crohn’s disease and ulcerative colitis are both IBDs. Crohn’s disease can occur anywhere along the GI tract from the mouth to the anus, while ulcerative colitis only affects the colon (large intestine).

- Ileitis is a type of Crohn’s disease that usually affects the ileum, which is the end of the small intestine, and also the beginning of the colon; however, there are also other forms of ileitis caused by other diseases.

- Several symptoms are common to celiac disease, Crohn’s disease, and ulcerative colitis: abdominal pain, diarrhea, weight loss, fatigue.

- Celiac disease is not classified as an IBD or IBS.

- Celiac disease is caused only by an intolerance to gluten. An intolerance to gluten is not the cause of Crohn’s disease (and ileitis), ulcerative colitis, or IBS.

I hope this will be helpful to you as well in your continuing education on celiac disease.