Ulcerative Colitis: Symptoms, Diagnosis and Treatment Guide

A stylised 3D anatomical illustration of the large intestine, including the colon and rectum, in blue and purple tones on a yellow background. Serves as the visual identifier for the Ulcerative Colitis condition card.

What is ulcerative colitis?

Ulcerative colitis (UC) is the most common type of inflammatory bowel disease (IBD), where parts of the large bowel, such as your rectum and colon, become swollen, inflamed and ulcerated.¹

UC occurs when the body’s immune system starts attacking the bowel, however when it comes to the exact cause of UC there's still a lot we don't know.¹ It can lead to diarrhoea, blood in stool, weight loss, fatigue and stomach pain, among other symptoms, however everyone can experience UC differently.²

There are different types of UC, depending on what part of the colon is affected. The most common types are:³

Proctitis

Inflammation of the bowel that is confined to the rectum (the final section of the large intestine that ends in the anus).

Proctosigmoiditis

Affects the rectum and the part of the colon next to the rectum called the sigmoid colon.

Left-sided or distal colitis

Inflammation that is found in the distal colon, this includes the rectum and the left side of the colon, also called the descending colon.

Total Colitis or Pancolitis

Affects the whole colon, if the inflammation affects most but not all of the colon it is referred to as extensive colitis.

Ulcerative colitis symptoms

The symptoms of ulcerative colitis (UC) depend on the severity and extent of the disease, as well as on which part of the colon is affected.² The likelihood of developing UC is almost the same for women and men and therefore, may not be linked to biologic gender.³ UC can be diagnosed at any age, although it most commonly occurs between the ages of 20-40 years.³

The main symptoms of UC are:¹

Diarrhoea
Rectal bleeding – visible blood in the stools
Urgency to defecate
Constipation
Generally feeling discomfort or weakness
Fever
Loss of appetite and weight loss
Fatigue (tiredness)
Abdominal pain

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Living with ulcerative colitis?

Find more advice and tips on how to take control of UC at our “Living With Ulcerative Colitis” page.

How is ulcerative colitis diagnosed?

Getting a diagnosis for ulcerative colitis (UC) can be difficult, and you may need several tests, including a physical examination as well as blood and stool tests.⁴ If you suspect you may have UC symptoms, consult your healthcare provider. They will ask you about your symptoms, general health and medical history. It is possible that some of the symptoms you may be dealing with can leave you feeling embarrassed or distressed.

Medical history

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Your healthcare team will as a first step take a full medical history including information about your overall health, diet and nutrition, when your symptoms first started, what medication you have taken, and your family history.¹⁴

Physical examination

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Your healthcare team will conduct a physical examination of the body. This can include your general wellbeing, measuring your heart rate, blood pressure, as well as an abdominal examination.¹⁴

Blood and stool test

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A full blood test can show whether you have inflammation anywhere in your body and if you’re anaemic.

Your stool can also be tested for signs of bleeding or inflammation, and to check whether an infection is causing diarrhoea. A faecal calprotectin test showcases whether you have inflammation in your gut.¹⁴

Endoscopy and biopsy

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Two further tests are performed to determine the cause of the symptoms and establish a diagnosis: an endoscopy and a biopsy. An endoscopy is a non-surgical technique that can involve either a) the insertion of a long, flexible tube (endoscope) through the mouth or the anus depending on where the healthcare professional wants to look that contains a tiny video camera, or b) the patient swallowing a tiny camera.¹⁴

MRI and CT scans

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Imaging tests, including magnetic resonance imaging (MRI), computer tomography (CT), or an ultrasound, can also be used to aid diagnosis and help monitor the disorder and locate areas of inflammation.¹⁴

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Want to know about long-term remission?

Find out how endoscopic remission could be the next step on your journey of long term healing.

Ulcerative Colitis:
What Is It? And How To Get Treatment