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Gastroenterology

A Gut Doctor Answers Your Crohn's Disease Questions

Stomach problems can lead you to a self-diagnosis of Crohn's disease. An expert weighs in on this complex condition.

Jonathan Fahler


woman lying on couch holding stomach in pain

Your gut’s telling you something isn’t right. And that this something is more than your run-of-the-mill stomach issue.

Any time your stomach problems are persistent or recurring, it can point to a more problematic underlying condition. Crohn’s disease is one of them. Along with ulcerative colitis, its cousin in the inflammatory bowel disease family, it affects more than 1.6 million people every year. And unlike other medical issues, this one often starts young — in your 20s and 30s.

We’re all quick to self-diagnose with a quick search of our symptoms. But Crohn’s disease is a complex condition that often befuddles the gut experts who know it best. Jonathan Fahler, DO, gastroenterologist at The Iowa Clinic’s Inflammatory Bowel Disease Center, tackled the 10 most common questions people have about Crohn’s.

What is Crohn’s disease?

Crohn’s disease is an inflammatory disorder of the bowel that affects all layers of the tissue within the bowel. Most commonly, it affects the end of the small bowel and the beginning of the colon. But you can have disease anywhere from the mouth to the anus.

How do you get Crohn’s?

We don’t know of any specific causes for Crohn’s disease. The biggest risk is family history. If you have family members that have it, you do have a higher risk of developing inflammatory bowel disease. There can be some association with a family history of other autoimmune diseases too, that might increase your risk of Crohn’s or any type of inflammatory bowel disease.

What’s the difference between Crohn’s disease and ulcerative colitis?

Ulcerative colitis only involves the colon — and only the surface layer of the tissue in the colon. It starts in the rectum and is usually continuous going further back in the colon or toward the beginning of the colon.

Crohn’s is not just on the surface. It affects the deeper layers of colon tissue and reaches other parts of the bowel. And it can skip around. You can have inflammation in two different parts of the colon and, in between, you’ll have normal-appearing tissue.

What are the signs of Crohn’s disease?

Crohn’s disease symptoms can be a little vague when compared to ulcerative colitis. It doesn’t have as characteristic a presentation.

With ulcerative colitis, usually, you have lower abdominal pain, cramping and frequent bloody diarrhea. Those are the same symptoms as Crohn’s disease but they can be a little more variable. Some people just have frequent diarrhea and it may or may not be bloody. Some people just have abdominal pain. In more serious scenarios, some people have a bowel obstruction that causes abdominal pain, nausea and vomiting.

That makes some of our investigative work more important in trying to decipher whether these symptoms are Crohn’s or something like IBS. There can be a lot of overlap in the symptoms.

It’s easy to jump to conclusions that if you have these symptoms, you have Crohn’s disease. Oftentimes, making a diagnosis is difficult and complex.

How is Crohn’s diagnosed?

It takes work at times to obtain a proper evaluation with lab testing, stool studies, imaging and endoscopic evaluation to put everything together.

Since the most common areas to see Crohn’s disease are at the beginning part of the colon and the end part of the small bowel, we use a colonoscopy to diagnose it and get biopsies to definitively say what’s going on.

But really, Crohn’s and ulcerative colitis appear similarly on a colonoscopy. It can be really red and angry. You can have ulcers. But we can’t see that deep layer. So we have to look at it in the context of what we’re seeing on the colonoscopy and in biopsies combined with other tests and medical imaging like a CT scan or MRI.

What are the different stages of Crohn’s disease?

We try to classify people based on their level of activity and severity of the disease. Using what we see endoscopically and what we see from a symptom standpoint, we collect and classify that.

That data guides on how we treat somebody, whether they have mild, moderate or severe Crohn’s disease. Obviously, if you have severe disease, we’re going to be very aggressive in treatment upfront. But Crohn’s disease is something that we tend to be pretty aggressive with treating anyway, because we want to avoid the complications of having an abscess, fistula or bowel obstruction that can require surgery and loss of bowel.

If you’re feeling symptoms, at what point should you go to the doctor?

If you’re experiencing Crohn's symptoms and they’re persisting, you should get evaluated by a gastroenterologist.

We see it present most often in the lower right side. So if there’s pain on the right lower side of your abdomen that’s persistent or gets worse after eating, that can be something. Or if you’re losing weight, running fevers, feeling very fatigued or have blood testing that shows you have anemia.

For children, if they’re not growing, that can be a sign they should come in and be evaluated.

How do you treat Crohn’s disease?

Most of the treatments for Crohn’s disease are similar to ulcerative colitis: medication, immunosuppressants, dietary modifications and lifestyle changes.

The one caveat to that is the topical, oral medication we use to treat ulcerative colitis. We just don’t have good evidence for treatment in Crohn’s disease because of how the topical medications work on the bowel. They only provide treatment for that surface layer. They don’t affect the inflammation that’s down in the deeper layers of tissue in the colon or small bowel.

Is there a special Crohn’s disease diet?

The Crohn’s diet follows the same recommendations of the ulcerative colitis diet. The only difference is if you have a narrowing of the colon or bowel. Then, we want you to limit your intake of more fibrous fruits and vegetables — food that has peels or rinds or things that could potentially lead to an obstruction if it gets caught up in that narrow area.

Do you eventually have to get surgery for Crohn’s disease?

Ideally, if we can control symptoms with medications and avoid surgery, we want to do that. We have seen some data and are doing a little better on that. So we’re learning how to use medications better and achieve the right therapeutic doses with them and monitor drug levels to know if you’ve developed antibodies to them. We’re better able to get you on the right therapy and keep you at the right therapeutic level to minimize the complications of Crohn’s disease.

Jonathan Fahler

JonathanFahler , DO

Dr. Fahler had the opportunity to work with our Gastroenterology (GI) physicians during his residency training in which they treated him as a colleague and showed great cohesiveness among the group. The GI team and the quality of The Iowa Clinic overall is why Dr. Fahler decided to join the practice. Early in his training, he worked in a GI Clinic where he developed a strong interest for disorders of the GI tract. That and the balance between clinical and procedural medicine are what attracted him to the field. 

In his free time, Dr. Fahler enjoys spending time with his family, exercising, and watching boxing & Minnesota sports teams.