IBD vs. Crohn’s disease vs. IBS: Symptoms, diagnosis, and treatment
Inflammatory bowel disease and irritable bowel syndrome can both cause abdominal discomfort and diarrhea. Inflammatory bowel disease is the term for a group of inflammatory conditions that affect the digestive tract, which include Crohn’s disease and ulcerative colitis.
While the symptoms of inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) can be similar, these conditions have different causes and treatments.
In this article, we look at the symptoms, diagnosis, and treatment of IBD and IBS, as well as the outlook for people with these conditions.
What is IBD?
IBD can cause irregular or painful bowel movements.
IBD causes inflammation of the gastrointestinal tract, which begins at the mouth and extends through the stomach and intestines to the anus. IBD is a long-term condition with no cure.
The two main types of IBD are ulcerative colitis and Crohn’s disease.
Crohn’s disease can affect any part of the gastrointestinal, or GI, tract. However, this type of IBD most commonly affects the small intestine and the start of the colon. Crohn’s disease can cause patches of inflammation that damage multiple layers of the GI tract wall.
Ulcerative colitis causes inflammation of the colon and the rectum. Unlike Crohn’s disease, it causes continuous areas of inflammation that only affect the innermost layer of the colon wall.
According to a 2014 review, Crohn’s disease is typically more severe than ulcerative colitis but is much less common.
Doctors do not fully understand what causes IBD, but they believe that it occurs due to a problem with the immune system. Genetics seem to play a role too as IBD can run in families. Certain lifestyle factors, such as smoking, can also increase the risk of developing IBD.
Common symptoms of IBD can include:
bloody stools and rectal bleeding
sudden urges to have a bowel movement
abdominal pain and cramping
a sense of the bowels not being empty after a bowel movement
unintended weight loss
Other symptoms may include:
loss of appetite and nausea
irregular periods in females
The symptoms can vary considerably from person to person depending on the location and severity of the inflammation. They also tend to come and go in cycles, so people experience flare-ups, when their symptoms suddenly get worse, and periods of remission, during which they have no or few symptoms.
To diagnose IBD, a doctor will typically start by taking a medical history and performing a physical exam. They may also order one or more of the following tests to aid their diagnosis:
X-ray or CT scan. These create an image of the inside of the body and allow a doctor to check for signs of any problems.
Endoscopy. This procedure involves inserting an endoscope, which is a thin tube with a light and camera on it, down a person’s throat into their GI tract to look for signs of IBD.
Colonoscopy. This test requires the insertion of an endoscope up through a person’s anus into their rectum and colon.
Blood tests. A healthcare professional can analyze a small sample of a person’s blood to look for signs of inflammation and rule out other conditions.
Stool tests. These require the individual to provide a sample of their stool for analysis. Doctors use stool tests to rule out other conditions.
A doctor will prescribe medication based on the severity of the IBD.
There is no cure for IBD, so the aim is to keep a person in remission. Doctors use treatment to relieve the symptoms that a person is experiencing, prevent flare-ups, and maintain periods of remission. The treatment that they choose will depend on the severity of the symptoms.
Many different medications are available for IBD:
Aminosalicylates, which help reduce inflammation. Doctors often prescribe these drugs to people with mild symptoms.
Immunomodulators, which can treat mild-to-moderate IBD and include steroids and azathioprine among other medications. Immunomodulators work by suppressing immune-system activity and reducing inflammation.
Biologics. Doctors tend to prescribe these drugs when other treatments have not worked. Biologics target specific parts of the immune system to reduce inflammation.
Some people may need surgery to remove or bypass damaged parts of their GI. However, according to the Centers for Disease Control and Prevention (CDC), surgery for IBD is becoming less common due to advancements in medications.