Episode 21 - The Sick Duel: UC vs CD

The following episode is a didactic activity. Our goal is teaching family medicine residents about these diseases and prepare them to treat their patients. We hope those who are suffering from these diseases do not find this activity offensive. May you find an appropriate treatment and get better. Consult your own family medicine doctor to learn more.

Similar but different, sound-alike but opposite, analogous but heterologous. 

Welcome to the Sick Duel, an epic comparison between two merciless opponents.

Our rivals today are: Ulcerative Colitis, “I will show you how to ulcer”; and Crohn’s Disease, “I will drill your guts”.

Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the GI tract. Ulcerative colitis and Crohn's disease are the main representatives of these disease. Today we will hear why they don’t get along and hopefully we’ll come to a good end.

Here we have our first guest

Arreaza: Who are you?

UC: Ulcerative Colitis is the name, and inflammation is the game. They say to save the best for last, so I tend to stick to the rectum and distal colon.  I like to come and go (no pun intended), creating episodic, mucinous diarrhea for my victims that is usually bloody.  I can be mild or severe, depending on the extent of mucosal involvement and level of inflammation.  

Arreaza: How do you manifest?

UC: I like to make my victims as uncomfortable as possible, creating urgency, pain, and constipation, while leaving them with a feeling like they aren’t “done” yet (aka tenesmus).  

Arreaza: I thought you said diarrhea, and now you mention constipation?

UC: Yes, I may cause periods of constipation when I am merciful, but diarrhea when I am cruel. Regardless of the thickness of the stools, I give them a mucinous and usually bloody discharge, sometimes leading to anemia. 

I like to attack extra intestinal organs such as the skin (causing pyoderma gangrenosum and erythema nodosum), the eyes (causing uveitis), and the joints (causing arthritis). Yes, my aunt Cronh’s can do some things right!

6. Arreaza: I’ve heard Ms Cronh’s is really mean. Where else do you go?

UC: Occasionally, I’ll make my way to the liver and cause primary sclerosing cholangitis.  My primary goal though is creating crypt abscesses and ulcerations.  If I’m lucky enough, I can progress to a fulminant, toxic level creating systemic symptoms and abdominal distention.  I hope to eventually make my way out of the GI tract through perforation (who doesn’t like a pinata?). 

Arreaza: I can see why your last name, colitis, can be deceiving, you can actually get out of the colon… Who are more likely to be your victims?

UC: I like to run in families. I prefer people who eat lots of fatty foods (Standard American Diet anyone?), high omega-6:omega-3 ratio, with history of previous bouts of gastroenteritis.  HLA autoimmune association, especially HLA-DR2. Even though smoking is a risk in many diseases, in my case, cigarette smoking may protect my victims from my attack, but if they smoked before and quit, I have a better chance to show up.

Arreaza: How do you get caught?

UC:  My victims tend to have chronic diarrhea for at least four weeks.  Because I am an inflammatory villain, many inflammatory tests can be non-specific such as ESR, fecal calprotectin/lactoferrin, etc.  Therefore, if you want me, you’re gonna have to come and get me.  Beware of your hospitalized patients, as a colonoscopy will greatly increase my ability to form a toxic megacolon and perforation!  Flexible sigmoidoscopy is recommended and will show you crypt abscesses, friable mucosa, decreased vascular markings and my continuous pattern of inflammation, yes, continuous, you gotta be consistent, unlike Ms. Crohn’s who likes skipping like a loser! 

How do you get eliminated? (What humans call treatment)

UC:  When my victims aren’t suffering as much as I’d like, those doctors first like to throw anti-inflammatories at me (such as mesalamine).  If that doesn’t work, they’ll throw in some steroids. However, if I’ve really done my job, then treatment usually starts with some immunomodulators (Azathioprine, Infliximab, etc.) followed by steroids with the goal of inducing remission.  If all else fails, they’re just gonna have to remove me along with my victims’ colon, so surgeons are their last resource to get rid of me!
Arreaza: What determines how bad you will be? (Prognosis)
UC:  Several factors influence my prognosis such as age of onset. Victims older than 50 have more chances to have a steroid-free remission. 

I hate smoking! Smoke does not let me grow, so when a patient quit smoking I can be more aggressive. 

When the intestinal mucosa heals early in the disease, my victims have a better prognosis. 

My chance of extension is higher in more distal areas, for example, patients with proctitis have 50% chance of extension. 

If my victims had an appendectomy before age 20, they have less chances of hospitalization and colectomy. 

With treatment, my victims may experience long periods of symptomatic remission along with intermittent exacerbations, although a small percentage may continue to have chronic symptoms and are less likely to achieve remission. The latter may require lifelong therapy or possible colectomy (Physicians 1, Me 0). 

Ulcerative colitis, you really know how to ulcer. Now we invite our next guest.

Arreaza: Who are you?

Crohn’s: Hi everyone, I’m Crohn's disease and unlike UC I don’t only affect the colon but I can affect any area of the GI tract from the mouth to the anus. Not only can I affect the whole GI tract but also, I can affect all the layers of the GI wall. Doctors like to call that “transmural inflammation”. Also, I can be sneaky, showing symptoms for a long time before diagnosis or I can happen all of a sudden and be diagnosed acutely.

How do you manifest?

Crohn’s: There are a few ways I can show up, but mainly I cause crampy abdominal pain, diarrhea either bloody or non-bloody, fatigue and weight loss. If I’m only located in the distal ileum, then I will give you right lower quadrant pain. 

Since I have transmural inflammatory forces, I can cause formation of sinus tracts that can result in abscesses or phlegmons. Phlegmon is a word that a lot of radiologist like to use and it pretty much means the formation of an abscess but not yet an abscess, so it can’t be drained but can treated with antibiotics. 

Sinus tracts can end up in microperforations or even fistulas. A fistula is when a connection forms between two tissues that are not supposed to be connected and, yes, it kinda sucks for my victims, especially when this connection happens between the bladder and the colon and you end up with urine mixed with feces coming out of either end. Ohh and if it connects from the GI tract to the skin then you may have continuous leakage of feces. WOW! I’m terrible, I know…

Arreaza: You are really mean!

On a lighter note, sometimes I cause no symptoms… at least not for a while until I make your GI tract so narrow that you defecate less frequently and end up having pain, and eventually your tract becomes obstructed. Man, yeah this pretty much sucks too. My bad!

Arreaza: I know you have more, tell us more about you.

I almost want to stop telling you anything else but there are a few more things. For example, I could give you aphthous ulcers in the mouth, pain in the esophagus or difficulty swallowing, abdominal pain, watery diarrhea, steatorrhea or oily diarrhea. OMG there's a bit more; last but not least some people may also have: arthritis of large joints, skin disorders like erythema nodosum or pyoderma gangrenosum and very few will experience hepatobiliary involvement such as primary sclerosing cholangitis or even eye issues like uveitis, iritis and episcleritis… among others.

Arreaza: You and your nephew UC really like going out of the GI tract, but I think you are more adventurous. Who are more likely to be your victims?

Crohn’s: Unlike UC, I actually like smokers, smoke helps me thrive! Those who have antibiotic exposure are at risk, also those with increased fats in diet, and maybe a little increased risk with NSAIDs and OCPs. Appendectomy may be a result of hidden CD vs a risk factor. 

If you want to avoid CD, high fiber and a Vit D supplementation are associated with decrease risk of CD. If you were breastfed, you have lower risk to get CD.

How are you caught? (diagnosis)

Crohn’s: You can usually suspect CD when there is a combination of suggestive features, such as RLQ pain, chronic intermittent diarrhea, fatigue and weight loss. Laboratory tests can show anemia, vitamin B12 and Vitamin D deficiency (malabsorption). Diagnosis is made certain via imaging, endoscopy and histological findings that show the aforementioned “transmural inflammation”. I think everyone will remember this “transmural inflammation” sign.

How can your victims fight you? (treatment)

Crohn’s: The treatment will be different depending on where I’am at, how bad I am and whether you want to stop me or keep me quiet. 

If I’m mild, then you can use oral 5-aminosalicylates like sulfasalazine or mesalamine, glucocorticoids, immunomodulators such as methotrexate or azathioprine; and biologic therapies such as infliximab, adalilumab, etc. Yep, these are some pretty tough names to combat a tough disease like me!

If I am moderate to severe then you’ll need a combo of meds: anti-TNF like infliximab plus an immunomodulator. The GI doctors are my archenemies! 

What determines how bad you will be? (prognosis)

Crohn’s: It can vary, most of the patients will experience a continuous progression while about 20% of patients can experience remission after initial presentation. Risk factors for progressive disease are smoking, age <40, perianal or rectal involvement, if glucocorticoids needed for treatment. Increased risk for cancer is for the most part unclear, and mortality is slightly higher than overall mortality in the general population. People with obesity have a higher rate of complications.

Dr Arreaza: Now we have the facts. You and UC belong to the same family, but are not the same!  What is the main difference between you two?

-UC: I’m limited to mucosa and submucosal layers, primarily affect rectum and distal colon, continuous inflammatory involvement, more likely to present with bloody diarrhea.  
-Crohn’s: I cause transmural inflammation, can affect any part of the GI tract, patchy distribution of inflammatory involvement. 

Any preference for age or sex groups? 

-UC: I prefer my victims be younger than 30 when I first attack, as this age range has been associated with poorer prognosis and higher relapses.  However, I tend not to go after the younglings.  Small preponderance for males.

-Crohn’s:  Any age is good for me.

Arreaza: And do you affect different parts of the colon?

-Both: Yes! 

Crohn’s: We cannot coexist. I can go to the Complete GI tract, get it? Chron’s “C” for Complete GI tract. Expansionist is my middle name!

-UC: UC stands for Unique to the Colon, and almost always the rectum. I know my territory.

Arreaza: So, I know you are very different, but what do you have in common?

Both, alternated: Blood, diarrhea, pain, inflammation, and extra-intestinal manifestations.

Arreaza: I knew we would find a common ground. Any final words?

Crohn’s: Yes, now that me and UC are on the same team, the IBD team. We have a message for celiac disease and Irritable Bowel Syndrome. 

UC: Yeah, this is for you, celiac and IBS, you got the guts to compare yourself to us? Bring it on! 

Now we conclude The Sick Duel: UC vs CD. Stay tune for more epic battles. 

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[This is the end of Rio Bravo qWeek. We say good bye from Bakersfield, a special place in the beautiful Central Valley of California, United States, a land where growing is happening everywhere.

If you have any feedback about this podcast, contact us by email [email protected], or visit our website riobravofmrp.org/qweek. This podcast was created with educational purposes only. Visit your primary care physician for additional medical advice. 

Our podcast team for this episode was Hector Arreaza, Claudia Carranza, Colby Kulyn, and audio edition by Suraj Amrutia. See you soon!