Kimberly Kearns, MS, APRN, on Diagnostics in IBD

Kimberly Kearns delves into the noninvasive and invasive diagnostic tools available to APPs working with patients who have or are suspected of having inflammatory bowel disease. 

Kimberly Kearns, MS, APN-BC is an IBD advanced practice provider with Duly Health and Care in Chicago, Illinois.

For maximum clarity of slides, use the Full Screen view.

TRANSCRIPT:

Hello, everyone, and thank you so much for joining us today on another lecture on inflammatory bowel disease. My name is Kimberly Kearns. I'm an adult nurse practitioner with a specialty in gastroenterology.

I've been in practice for 17 years, and it is my joy today, of course, to share with you some more information about inflammatory bowel disease. So let's get started.

First of all, let's begin with some IBD basics. IBD affects as many as 3.1 million persons in the United States. This equates to approximately 1.3 % of the population with about 70 ,000 new cases each year. Now, before we go any further, let's remember that inflammatory bowel disease actually consists of two subtypes, right? Crohn's disease and ulcerative colitis. So when we're talking about inflammatory bowel disease, remember that there's an umbrella for both of these terms.

Now, when we're talking about inflammatory bowel disease, we have to recognize that over the past 50 years, there's definitely been an increase in both the incidence and prevalence of inflammatory bowel disease, specifically in some newly industrialized countries. Diagnosis is usually made in the second and fourth decades of life, with just a bimodal age distribution of IBD, again, that first peak in the second and fourth decades, and the second peak, of course, around the sixth decade of life.

IBD remains a significant cost to US health system. It accounts for 1.3 million provider visits and 92,000 hospitalizations annually. IBD patients incurred over 3 times higher annual cost than non-IBD patients. That was about 22,000 versus 7,000 per member year claims per visit.

And of course, our bigger drivers of cost when it comes to inflammatory bowel disease ends up being therapeutics, specifically our advanced therapies; comorbidities, including anemia and psychiatric illnesses; and of course, emergency room visits.

Now, as we start moving forward, right? Let's talk about some of the diagnostic tests. We're talking about making that diagnosis, but how do we do that? So let's look at our diagnostic tools that we have for inflammatory bowel disease. Now we've got both noninvasive testing and of course invasive testing. So let's start off with some of our noninvasive testing, right? So this of course would be stool testing and of course blood testing.

So what we're looking at here first and foremost is the fecal calprotectin and we see the utility I've got mentioned up here both in prone disease and ulcerative colitis. So the fecal calprotectin, remember, it can be elevated, but usually is more elevated with someone who has colonic disease versus small bowel disease. So again, if they only have small bowel disease, this number might not mount this high.

And again, sometimes the utility of that in Crohn’s disease can be a little bit less than of course in those with ulcerative colitis. Because again, we definitely see there's an increase in colonic. So pros, of course, it helps us to follow it when it's initially elevated. I kind of use this as a trender. And also, for myself, this is actually how I know that how a patient is responding to therapy. I usually use it as a baseline, and I continue to follow it. But also, recognize that I use it when I'm wondering if a patient is starting to lose a therapeutic response or if they're about to go into a flare.

What are some of the cons of using fecal calprotectin? Of course, it could be elevated for other reasons, including that of infection, and, of course, maybe low, despite active small bowel disease. And I will tell you, I have seen elevated fecal calprotectin, even on patients who have had inflammatory polyps as well. So, kind of keep that in mind when we're ordering a fecal calprotectin.

How about a CRP? Now, before we start with CRP, we recognize that in Crohn's disease, it is typically elevated and ulcerative colitis, not always a marker that could be elevated. But again, 40% of patients with a mild inflammation, with mild inflammation, by the way, do not mount a CRP or a sed rate response. So keep that in mind. If it's a very mild form of inflammation, that CRP might not mount right away, so that might not be an elevation. And there is a population of patients that actually don't make CRP. So again, you kind of have to keep that in mind when you're looking specifically at this blood test, again, the CRP. T

he pros, of course, it's helpful to follow if initially elevated. But again, if it's not initially elevated, this might be not the blood test to use or the noninvasive testing to use. Some of the cons with this is it also can be elevated for other reasons, for infection or even underlying inflammation, right? So it's not specific to the gut. We talked about fecal calprotectin though, right? That's more specific to the gut where a CRP of course is not.

How about a hemoglobin? Of course, we know that we trend these specifically for patients who have chronic inflammation. Again, the pros, when we see that our hemoglobin is of course increasing, we can assume that there's some healing going on. And if it's decreasing, we can suggest that maybe there are some inflammation or recurrence. But again, might only be lower if there's advanced disease.

I really do follow albumin levels, especially in my patients who have active inflammation because we know that they can be low in both ulcerative colitis and Crohn's disease. And again, just like our hemoglobin, when we see that this albumin is increasing, we are presuming that there's healing, but if there is decreasing, we're looking for recurrence.

Unfortunately though, albumin doesn't change very acutely, especially in that setting. So again, it's good to kind of use it more as a trending. And when I'm looking at someone who's got severe disease, which we're going to get to in a bit, albumin level is very important.

So now let's take a minute and look at some radiology testing that we would utilize in order to make the diagnosis for inflammatory bowel disease. Let's start with CT enterography, right? We can use CT enterography to diagnose and follow small bowel disease when it comes to Crohn's disease. And how about for ulcerative colitis? Well, it might be good to rule out any kind of small bowel involvement specifically, right? So we're going to rule out Crohn's disease with that.

We know that CT enterography is a rapid exam. Images, of course, are less user-dependent. But the cons, of course, include radiation, IV contrast, especially those with chronic kidney disease and again, for myself, even in my clinic, I want to make sure that my radiologist is very familiar with reading CT enterography.

How about MR enterography? And I'll tell you, this is where I've leaned most in regard to doing imaging on my IBD population, specifically my Crohn's population, again, to diagnose and follow small bowel disease. It is a great test in order to really look for small bowel involvement.

Also, again, in the utility for ulcerative colitis, it's more to use to rule out Crohn's disease. The pros with this, that we don't have any radiation, you can use it as serial monitoring. There's less risk in front of kidney disease. But of course the cons are it's a prolonged exam and of course can at times be relatively expensive.

Now let's talk about more of our invasive testing, right? Colonoscopy. Of course we all know that we need a colonoscopy to diagnose assessed extent of disease and follow colonic disease and even terminal ileum disease activity when it comes to Crohn's and when it comes to ulcerative colitis, again, diagnosing, assessing, extensive disease and following disease activity in the colon.

We know that the pros, of course, include direct visualization and biopsies— really tells us about what's going on inside the colon. The cons, of course, with colonoscopy, there's minimal role sometimes in getting into beyond a little bit of the terminal ileum. Patients, of course, don't always appreciate the bowel prep, sedation, days off, and of course, the underlying complication that goes along with colonoscopy.

And the last thing when I mentioned in here for right now, of course, is a capsule endoscopy, which of course, we used to diagnose –it follows more of small bowel disease, and again, more to from an ulcerative colitis perspective, again, to rule out Crohn's disease. From a pros perspective, there's a lack of radiation, the cons perspective, of course, that there is still a bowel preparation involved. There's a small risk of retention, and that risk, of course, is less than 6% in patients, but I will tell you it is a great diagnostic tool.

And before we move on from diagnostics and inflammatory bowel disease, it would be ill of me not to mention bedside ultrasound, which we are now using a lot to evaluate bedside evaluation of inflammation of the small intestine, especially in our Crohn’s disease. We are saying lots of tertiary care institutions perform bedside ultrasound to re-evaluate extensive disease and of course even overall inflammation if present. I can tell you in a community-based practice we don't have this, but I will tell you from a diagnostic perspective, this is something that is available and I think in the future we'll definitely see it in the community as well.