Ulcerative colitis and Crohn’s disease are two of the most common types of Inflammatory Bowel Disease (IBD). Individuals with IBD experience both inflammation and damage to the gastrointestinal tract. While IBD requires lifelong treatment, the severity of symptoms that each disease presents varies among individuals. Flare-ups may range from mild to severe and while for some individuals’ flare-ups may calm down quickly with treatment, others may take months to properly respond to treatment. Both of these diseases are similar in numerous ways, but there are also key differences among the two that set them apart in regards to effects on the body and treatment plans.
Crohn’s and UC are similar in some ways
Crohn’s disease is a chronic inflammatory disease that can affect any part of the gastrointestinal tract, from the mouth to the anus. Ulcerative colitis is also a chronic inflammatory disease; however, it is limited to inflammation in the large intestine. Both Crohn’s disease and ulcerative colitis present similar symptoms: abdominal pain, cramping, diarrhea, frequent stools, bloating, nausea, vomiting, fever, constipation, loss of appetite and weight loss, but there are a few differences between the two. For individuals with Crohn’s disease, abdominal pain may manifest itself anywhere within the abdomen; however, for individuals with ulcerative colitis, abdominal pain tends to be restricted to the left side of the abdomen. Moreover, rectal bleeding (blood in the stool) is much more common in individuals with ulcerative colitis as opposed to those with Crohn’s disease.
The cause of both is not well understood
Both researchers and healthcare professionals do not understand what triggers the onset of both of these diseases, but they do hypothesize that a few factors may play a role in their manifestation. Such factors include genetics, diet, environmental factors, gut microbes, vascular problems, mental health problems, and certain medications. For Crohn’s disease, inherited genes tend to increase an individual’s risk of the disease. In addition, when certain bacteria or viruses enter the body, they can trigger a malfunction in the immune system and lead white blood cells to attack the gastrointestinal tract. Smoking is also associated with an increased risk of the disease. For ulcerative colitis, it too is triggered by faulty genes and poor function of the immune system.
“If an immediate family member (sibling, parent) has IBD, your risk of being diagnosed is significantly increased. If a second-degree family member (aunt, uncle, cousin, grandparent) has IBD, there is a slightly higher risk of having Crohn’s disease or UC. Despite this, we know that more than 80% of patients with IBD don’t have any family history of this – so, there’s more going on than just genetics. Scientists have identified about 160 different genes that increase the risk of developing IBD, independent of environmental factors, but genetics still don’t seem to explain the whole story,” stated Dr. Nikhil Pai, pediatric gastroenterologist and Jelena Popov, pediatric gastroenterology research coordinator.
The diagnosis process is similar
Diagnosing both Crohn’s disease and ulcerative colitis commonly involve x-ray scans and endoscopy. Moreover, leukocyte scintigraphy may be used to diagnose these diseases by way of scanning the white blood cells. In leukocyte scintigraphy, a camera is used to monitor white blood cells (which are typically bound to inflammation) and determine the intensity and severity of inflammation. In terms of treatment, there is no surgical cure for Crohn’s disease. Still, it can be managed with medication. Following diagnosis, a majority of individuals may not be able to work for at least a year and they may experience occasional flare-ups. For ulcerative colitis, it too can be managed with medication, but a proper diet is equally important since some foods may act as triggers and aggravate the disease. Unlike Crohn’s disease, a surgical procedure, known as colectomy, can be performed in those with ulcerative colitis to alleviate symptoms of the disease to a large extent. “This is a surgery that involves removing a patient’s colon. This treatment can cure UC, since in UC, the disease only affects one’s colon. That’s why once the colon is removed, there is technically no disease left. Unfortunately, the same is not true for patients with Crohn’s disease. Because Crohn’s can affect anywhere in the digestive tract, it is not practical for doctors to remove the affected area or areas – because it can just come back in another section of the intestines,” stated Dr. Nikhil Pai and Jelena Popov.
Increased mortality rates associated with surgery
While both Crohn’s disease and ulcerative colitis are chronic diseases, ulcerative colitis may be considered “worse” because individuals with severe ulcerative colitis may require surgery. For older individuals (over the age of 50), surgery has been associated with increased mortality rates due to the presence of colitis-associated postoperative complications. Moreover, if ulcerative colitis goes undiagnosed or untreated, uncontrolled inflammation can spread and cause problems to the other organs within the body. It can lead to more severe symptoms such as abdominal pain, cramping, and persistent diarrhea, as well as cancer. For this reason, even if an individual is doing well in coping with ulcerative colitis, it is vital that they see a gastroenterologist on a regular basis to monitor for any cancerous changes within the colon.
The prognosis for both Crohn’s disease and ulcerative colitis is fairly good in that individuals tend to respond well to medical therapy and avoid possible triggers that may aggravate their symptoms. While symptom-relief and next flare-up is unpredictable, being aware and educated on the subject is an important part of becoming an active participant in one’s own health and treatment plan. “So, these are some of the types of treatments that are out there in the pipeline, and I think there is a lot of room for hope. If you look at examples of other diseases where there have been breakthrough discoveries, oftentimes the discovery for what causes the condition comes out of left field, and you wouldn't have necessarily predicted it based on the research. This whole area of biologics is very promising, and if we can target these important inflammatory molecules, that's going to be an important area. Obviously, TNF has been an important molecule, but there are other biologics in the pipeline,” said Dr. Edward Loftus, gastroenterologist specializing in the evaluation and management of patients with ulcerative colitis and Crohn's disease.
There is a lot more to learn
“I think we always worry we are missing something really obvious. You look back over 50 years, and these diseases were much less common. It's interesting watching over different parts of the world where they never saw IBD, and now they are starting to see it. As a country becomes more industrialized and more like a Western country, they start seeing more IBD. So, is it something else entirely? Is there an environmental trigger that we are missing? Is it in the food? Is it in the water supply? Is it a toxin? I don't know, but I always worry about that in the back of my mind. There are many challenges ahead with the treatment of Crohn's and colitis, and certainly no one medication has universal benefit. But with the right approach, with a doctor who is familiar with the condition, a particular medication or combination of medications may be helpful in controlling symptoms. And the good news is that in the last year we have seen lots of new treatments, and then we look in the research pipeline, and there are even more treatments in the pipeline,” concluded Dr. Loftus.