IBD: Crohn's disease (CD) vs ulcerative colitis (UC)

Written by: Dr Evangelos Russo
Published: | Updated: 04/11/2019
Edited by: Emma McLeod

Inflammatory bowel disease causes inflammation of the gastrointestinal tract and is a chronic condition, meaning that it is long-term. The two most common and well-known types of IBD are Crohn’s disease (CD) and ulcerative colitis (UC), and Dr Russo, an expert in treating inflammatory bowel disease, explains these two commonly confused conditions.


A woman is lying down on a couch clutching her stomach in discomfort


How common are Crohn’s disease and ulcerative colitis?

Unfortunately, for reasons which are not entirely clear, Crohn’s Disease (CD) and ulcerative colitis (UC), collectively known as inflammatory bowel disease (IBD), are becoming increasingly common in the western world.


The current frequency is between 1 in 200 to 1 in 500 people, but there are estimates suggesting than in the next 20 years they might affect up to 1% of the general population.


What are the common symptoms of Crohn’s disease and ulcerative colitis?

Crohn’s disease can affect various parts of the gut – from the mouth to the anus. Symptoms, which tend to vary depending on its location and severity, can include the following:


Ulcerative colitis, unlike Crohn’s disease, can affect specifically the colon and rectum. The most frequent symptoms in UC are:

  • Bloody diarrhoea
  • The urgency to use the toilet.


Both Crohn’s disease and ulcerative colitis can often affect other systems, most commonly joints, the skin and the eyes, so we always enquire about these when taking a history from patients with suspected IBD.


It is important to remember that in addition to inflammation, patients with IBD are more prone to symptoms caused by conditions such as irritable bowel syndrome (IBS), which is often confused with inflammatory bowel disease. So, even though the inflammation itself may seem to be in remission, or under control, an open-mind is required by a physician in order for the holistic needs of these patients to be met.


How would a doctor distinguish between Crohn's disease and ulcerative colitis?

In order to make the distinction between Crohn’s disease and ulcerative colitis, we look at the symptoms, the exact location of the inflammation and whether the pattern of the inflammation is continuous or interrupted. Moreover, we look at some characteristic patterns on biopsy specimens from various parts of the digestive system.


It’s important to note that up to 15% of patients with IBD will have their diagnosis changed from ulcerative colitis to Crohn’s or vice versa at some point in the patient journey.


Which of these conditions is more serious?

Both CD and UC can vary significantly in terms of their severity. They can be:

  • Very mild
  • Have limited inflammation which is relatively easy to treat
  • Have more persistent inflammation which is resistant to many treatments


Therefore, severity is not disease-dependent but can vary from patient to patient. On the whole, however, patients with Crohn’s disease can have a more active form of the condition, requiring stronger medication and more frequent surgical care than patients with ulcerative colitis.


What are the main treatments for these diseases?

Crohn’s and ulcerative colitis are usually treated with either tablets or injectable medications, which could be self-administered injections under the skin (subcutaneous injections) or injected directly into the vein (intravenous infusions). As these diseases are inflammatory in nature, the majority of these medications work by blocking elements of the immune cell pathways that trigger inflammation in the gut.


Often, when several medications fail to get symptoms under control, or, in the case of Crohn’s when the disease affects a very limited portion of the bowel, an operation is required to remove the diseased segment.


If you’re experiencing symptoms of inflammatory bowel disease, don’t hesitate to get in touch with Dr Evangelos Russo who will be able to provide you with a diagnosis and treatment. You can get in touch by booking a consultation via his profile.

Dr Evangelos Russo

By Dr Evangelos Russo

Dr Evangelos Russo is a skilled gastroenterologist based in London. He specialises in diagnostic and therapeutic endoscopy, colonoscopy, and polypectomy, and is an expert in treating inflammatory bowel disease (IBD), chronic diarrhoea, and acid reflux, among other conditions.

Dr Russo gradutated from University College London in 2003. He completed further training on the North West Thames rotation, while also earning a PhD in translational medicine from Imperial College London for his research on imaging techniques in the diagnosis and treatment of Crohn's disease.

With his appointment as Consultant Gastroenterologist at Imperial College Healthcare NHS Trust, he has established himself as a core member of the multidisciplinary team that treats lower gastrointestinal (GI) cancer. He has been involved extensively in research into IBD and his work has been widely published. He is also an honorary clinical lecturer at Imperial College London.

We use cookies on this site to enhance your user experience. Click ‘Enter’ to continue browsing. Enter Cookies policy