Differentiating IBS and IBD
Interviewer: Dr. John Valentine is an expert at treating inflammatory diseases of the intestinal tract, including inflammatory bowel disease, or IBD as some people know it. First of all, is there a difference between irritable and inflammatory bowel disease?
Dr. Valentine: Those two get confused quite often.
Interviewer: Okay.
Dr. Valentine: So irritable bowel syndrome is quite common. It is not inflammatory, can give you abdominal pain, cramps, diarrhea, or constipation. But inflammatory bowel disease is an immune-mediated process that causes inflammation in the GI tract that can result in similar symptoms, abdominal pain, and diarrhea. But because of the inflammation, it can also lead to bleeding in the GI tract, fevers, and complications such as the development of cancer if there's long-term inflammation, and the need for surgery.
Interviewer: So it's a little bit more of a nasty character?
Dr. Valentine: Yeah, I agree.
The Rise of Inflammatory Bowel Disease
Interviewer: Yeah, okay. So I hear that inflammatory bowel disease is actually increasing quite a bit. Can you talk to how much?
Dr. Valentine: Well, it's increasing in both western countries, and then in countries that are now westernizing. China, India, and South America are now starting to see an influx of inflammatory bowel disease and exactly why isn't clear. But because patients are diagnosed very young and we can't cure it, we can treat it, these patients are living with it. With the increased rate of new cases, some predictive modeling suggests that the number of people living with inflammatory bowel disease in North America will double in the next 10 years.
Interviewer: That doesn't sound very enjoyable for a lot of us, then.
Dr. Valentine: Well, fortunately, we have multiple treatment options. We can treat this, but we can't cure it.
Diagnosing Inflammatory Bowel Disease
Interviewer: All right. In another segment, we'll talk about treatment options for IBD. Because from what I understand, there are quite a few of them and it's probably worth its own particular podcast. So take me through the process that you'd use to diagnose someone's IBD.
Dr. Valentine: Well, typically a patient would come in with chronic symptoms. An infectious colitis, for example, of Salmonella, or Shigella, the common bacterial infections, you may have similar symptoms, but they'll only last three to five days. If somebody comes in having blood in their stool, loose stools, maybe fevers and it's been going on for a couple of weeks, then we start thinking about inflammatory bowel disease. Which we then need to differentiate between ulcerative colitis, which only involves the lining of the colon, and Crohn's disease, which can be anywhere in the GI tract, but tends to like the end of the small intestine, the first part of the colon.
Interviewer: Are the symptoms for all those the same? Or do you use a little bit of a different diagnostic then to figure out specifically what somebody might be dealing with?
Dr. Valentine: Well, there is a tremendous overlap between the two. Where the inflammation is can make a big difference. If your inflammation is only at the very end of your small intestine, you may not have diarrhea at all. Where if the inflammation is in the rectum and lower part of the colon, then diarrhea and visible blood would be a more common feature. So we can get some hints as to which one we think it is, but we need to do some more diagnostic testing to straighten that out.
Family History and Risk Factors
Interviewer: In addition to symptoms, are there other risk factors that you ask the patient about to help determine if that is indeed what they have?
Dr. Valentine: The risk factors don't exclude it, but it certainly increases the probability.
Interviewer: Okay.
Dr. Valentine: So the biggest risk factor we know for having inflammatory bowel disease is having a family member who has it. That being said, somebody needs to be first. But there's often a cluster of other immune-mediated diseases in the family, multiple sclerosis, rheumatoid arthritis, lupus, or celiac disease. These are all different diseases that do share some genetic underpinning so that's why they tend to cluster together.
Interviewer: Do you find that patients do a pretty good job of self-diagnosing by the time they get to you?
Dr. Valentine: It depends. If they have a family member, especially a brother or sister with it, yeah, they know what the symptoms are and they come in, "I think I sort of have this." If they're the first in the family, they really don't know.
Interviewer: Okay. So what are some of the other diagnostics that you use to determine for sure if they have inflammatory bowel disease?
Dr. Valentine: Well, the number one cause of bloody diarrhea is infection so you always need to rule out infection. Sometimes, though, the infection can be the trigger. We treat that, but the inflammation won't go away.
Interviewer: Okay.
Dr. Valentine: So we have to rule out infection. The patient's age also can give you some hints.
Interviewer: Okay.
Dr. Valentine: So ulcerative colitis and Crohn's, they're a peak onset stage of 15 to 25. It can occur a whole lot younger. It can occur in the 60s. But a 25-year-old coming in with diarrhea for several weeks with blood in it, inflammatory bowel diseases goes to the top of my list.
Diagnostic Tests: From Infection Screening to Colonoscopy
Interviewer: Are there any tests or screenings that you use?
Dr. Valentine: A colonoscopy would be the primary diagnostic test. You want to be sure you know what you're treating, especially because some of the treatments involve immunosuppressant medications. So a colonoscopy, make sure you know whether it's ulcerative colitis or Crohn's. Make sure the pathology, what the pathologist sees under a microscope fits with that diagnosis and not some other bizarre or much less common etiologies.
If the colonoscopy doesn't reveal any problems, then imaging of the small intestine, and there are several ways of doing that. An MRI or a CT scan would be most common. Occasionally, the capsule endoscopy, but I'm really wary of people who get diagnosed based on images from a capsule endoscopy by itself.
Interviewer: Why is that?
Dr. Valentine: Lots of things can cause inflammation in the small intestine. Little discreet breaks could be caused by taking ibuprofen and similar types of medications. So when they even show these pictures to the experts, they have a hard time deciding what might be due to these ibuprofen-type medications and what might be due to Crohn's disease.
When to Consult a Specialist About IBD
Interviewer: At this point in our conversation, if somebody is convinced at this point that they have inflammatory bowel disease, would they go to a general practitioner or their primary care physician first? Or come straight to you at this point?
Dr. Valentine: Well, like I said, need to exclude infection. So I think going to the primary care doctor to get the stool studies done to exclude Clostridium difficile infections, Salmonella, Shigella, campylobacter, the other bacteria that can cause inflammation in the colon would be the first step.
updated: November 14, 2024
originally published: March 15, 2016