Ulcerative Colitis: Causes, Symptoms, Diagnostics

Ulcerative Colitis: Causes, Symptoms, Diagnostics
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Ulcerative colitis is a long-term inflammatory disease of the terminal part of the large intestine, with possible spread to the whole colon. This autoimmune inflammation is characterised by bleeding, suppuration and ulceration of the intestinal mucosa. Its cause has not been clarified. It is characterised by alternating periods of calm and the onset of discomfort such as pain, diarrhoea and bleeding on stool.


Ulcerative colitis, also called Colitis ulcerosa (CU), is a long-term non-specific inflammatory disease of the colon.

It is a life-long condition.

Inflammation of the intestine has a hemorrhagic (bleeding) - catarrhal character, with the possible formation of ulcers in the intestinal mucosa. The word catarrh refers to a type of inflammation of the mucosa in which mucus is formed to an increased extent.

It arises on an autoimmune basis and its cause is not clarified.

Ulcer is the name for an ulcer, and from this the name ulcerative colitis is derived.

It mainly affects the end part of the large intestine, the rectum. However, it can also occur in other parts of the bowel, or it can affect the bowel throughout its entire course.

Inflammation is located in the mucosa and submucosa layer. Not in the entire thickness of the intestinal wall, as it tends to be in Crohn's disease.

Ulcerative colitis was first described in 1859 by the London physician Samuel Wilks. In 1948, the first Czech internist Dr. Zdeněk Mařatka.

Globally, the incidence of the disease is reported to range from 0.5 to 24.5 per 100 000 affected population per year. Higher figures belong to developed countries such as in North America, Europe or Israel.

In the United Kingdom 10 per 100,000 people newly develop the condition a year while the number of people affected is 243 per 100,000. Approximately 146,000 people in the United Kingdom have been diagnosed with UC. (Source: Ulcerative colitis - Wikipedia)

Ulcerative colitis most often breaks out between the ages of 20 and 40. Alternatively, between the ages of 50 and 60, and it is reported that about 15% of patients are over 60 years of age.

The prevalence of the disease between the sexes is approximately equal, although some sources report a slight over-representation for women.

This type of colitis has symptoms that are mainly associated with the digestive system. These are abdominal pain, diarrhoea or bleeding during stool, i.e. enterorrhagia.

However, it is also characterised by extra-intestinal complications when it affects, for example, joints, eyes or skin. Its serious risk is the development of colorectal cancer (after years of disease) or damage to the liver and gallbladder.


Ulcerative colitis is also referred to as an autoimmune disease. But its exact cause has not yet been clarified.

The association of a combination of different risk factors is reported.

There is a higher prevalence of the disease in developed countries, indicating the influence of environment, lifestyle, reduced exercise and low fibre intake.

Similarly, blame is attributed to the intake of higher amounts of refined sugar and various chemicals used in the food industry. The influence of the use of medicines, namely hormonal contraceptives or non-steroidal antiphlogistic drugs, is possible.

Family history of the disease also increases the risk.

Interestingly, a protective effect of smoking is reported, i.e. smokers are less at risk. It has also been found to occur at a lower frequency in people after removal of the appendix.

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Risk factors and combinations thereof that can lead to the development of ulcerative colitis:

  • occurs mainly between the ages of 20 and 40 or between the ages of 50 and 60
  • autoimmune influence, disorder of mucosal immunity
  • family history and genetic factors (HLA DRB1*0103, MDR1, MY0B9 in severe colitis)
  • environmental impact
    • industrialisation
  • lifestyle
    • less physical activity, sedentary lifestyle, sedentary work
    • reduced fibre intake
    • increased intake of refined sugar, chemical additives in food
  • taking medicines such as hormonal contraceptives or non-steroidal anti-inflammatory drugs


Ulcerative colitis has symptoms associated with the digestive system, as the inflammation affects the intestine.

However, they are also associated with general discomfort and various extra-intestinal symptoms. The disease is long-term, i.e. chronic, or life-long.

Colitis of this type is characterized by having a period of difficulties that is referred to as a relapse. Relapse is subsequently followed by remission, which is the term for a symptomless, asymptomatic phase.

The typical symptom of the disease is diarrhea with an admixture of blood and mucus.

The mild form of ulcerative colitis is characterised by diarrhoea, with an admixture of blood and mucus in the stool. The frequency may be 2 - 3 times during the day. And especially in the morning.

Typical is tenesmus, which is a painful urge to pass stool, followed by emptying a small amount of stool and a feeling of incomplete, imperfect emptying of the rectum. 

These symptoms are also characteristic of involvement of the terminal part of the colon, i.e. the rectum

The severe form is characterized by watery and bloody stools, in number even 10 times a day. Of course, a painful urge to stool is associated. Abdominal pain is also present outside the time of defecation. The abdomen is distended. The body temperature rises.

Massive bleeding presents with anemia, weakness, pallor, tachycardia occur. The person loses body weight and is also at risk of internal disruption.

This form is also referred to as fulminant ulcerosis.

Its resolution requires hospitalization, infusion therapy and even blood transfusion.

Ulcerative colitis is classified according to the site and extent of colonic involvement:

  1. distal colitis
    • proctitis, affecting the anus, i.e. rectum (20 %)
    • proctosigmoiditis, affecting the rectosigma (35%), i.e. both the rectum and the oesophageal part of the colon
  2. left-sided colitis (20%), affecting the left side of the intestine, i.e. the descending colon
  3. pancolitis, which is a term for involvement of the entire intestine (15%)

The disease is also classified on the basis of frequency:

  • chronic relapsing course, with one episode per year
  • chronic intermittent course if there is more than one episode of distress per year
  • chronic persistent course, with continuous activity
  • fulminant progression is the most severe type

Table: Truelove and Witts Truelove and Witts severity index

Mild Moderate Severe Fulminant
Bowel movements
once a day
fewer than 4 4 - 5 nad 6 nad 10
Blood in stools little some blood bloody stool pure blood
Body temperature no elevation 37 - 37,8 above 37,8 nad 37,8
Pulse up to 90/ minute up to 90/ minute up to 90/ minute up to 90/ minute
Haemoglobin level above 140 100 - 140 below 100 below 80
Blood sedimentation
in hour 1
below 30 below 30 above 30 above 30
Other no tachycardia
mild anaemia
moderate tachycardia
moderate anaemia
severe abdominal pain
severe anaemia
weight loss

In addition to difficulties with the digestive tract, ulcerative colitis is characterized by extraintestinal symptoms and complications.

Bleeding can cause anaemia, followed by weakness and fatigue, and other discomforts are also associated, as can be seen in the table. The body temperature rises, the pulse rate accelerates. Inappetence and weight loss are present.

Extra-intestinal difficulties further include:

A serious complication is colorectal cancer, the risk of which increases with time. After 10 years the risk is about 2% and after 50 years of disease it is 40%.

In the severe form of colitis, megacolon toxicum also occurs. Which arises as a consequence of enlargement of the large intestine, increased flatulence.

The risk is subsequently its rupture, leakage of intestinal contents from the intestine and the development of peritonitis, i.e. inflammation of the peritoneum, which is life-threatening.

As a result of inflammation, damage to the intestine, ulceration, or ulceration, occurs. After years and repeated episodes, the wall of the intestine is scarred, the intestine is shortened and its lumen narrowed. Repeated inflammation is the result of fistula.

The disease negatively affects the affected person's psyche and performance. Disability is also one of the complications of the disease.


Diagnosis of the disease is based on medical history. Thus, frequent diarrhea, rectal bleeding, but also abdominal pain or weight loss. A person is pale, weak, inefficient.

On physical examination, the abdomen is observed, resistance to palpation of the abdomen, especially in the left lower abdomen. 

Next, laboratory tests are done to determine the diagnosis. Inflammatory markers are elevated, but also anemia is present.

Biochemistry can reveal changes in the internal environment, electrolytes. Complementary are liver tests.

Next, antibodies, and thus pANCA and ASCA serology. The infectious cause of inflammatory bowel disease can be determined by stool examination and culture of bacteria or the presence of parasite eggs proven microscopically.

The most important part of the diagnosis of ulcerative colitis is the endoscopic examination of the intestine.

A colonoscopy is performed. With endoscopy, the finding and, in particular, inflammatory changes in the rectal area are found. And, according to the form, also the rest of the colon. During endoscopy, ulcerative colitis is also distinguished from Crohn's disease.

During the endoscopy, the material is also collected. The collection is followed by its histological examination.

Other imaging methods include sonogram, or ultrasound, and CT or MRI. It is important to differentiate ulcerative colitis from Crohn's disease.

Table: differences in the diagnosis of ulcerative colitis and Crohn's disease

Ulcerative colitis Crohn's disease
Affection of part of the intestine colon
especially the rectum
without small intestine involvement
the entire digestive tract
mainly the end of the small intestine
Affection of the wall of the intestine mucosa and submucosa celá hrúbka črevnej steny
Extent of disability continuously from the anus upwards segmental disability
alternation of healthy and damaged sections
Bleeding often less frequently
Tenezmy Present absent
Antibodies ASCA negative
p-ANCA positive
ASCA positive
p-ANCA negative
Clinical picture bloody diarrhoea abdominal pain
weight loss
Complications risk of cancer formation of fistulas, stenoses and abscesses


The course of the disease is long-term, lasting even a lifetime. It is most common in people at a young age, from 20 to 40 years of age. Subsequently, the second period of disease onset is typically between the ages of 50 and 60.

Ulcerative colitis is characterised by alternating relapses and remissions.

A relapse is a period of time when difficulties set inRemission is the subsequent abatement of symptoms. How often they relapse is individual. The basic manifestations include diarrhea with the presence of mucus and blood, a painful urge, and the subsequent subsidence of pain after voiding.

Which is significant for the lighter form.

More severe conditions are characterized by abdominal pain even outside of defecation and higher bleeding intensity and frequency of defecation. This, in turn, affects the general condition, i.e. weakness sets in, also on account of anaemia.

Physical fitness decreases, but also body weight, one suffers from lack of appetite. The association of extra-intestinal discomforts and their degree is also individual.

For the onset of difficulties, some possible triggers are listed.

Examples are stress, certain foods containing chemical additives, and the previously mentioned medications. However, a relapse of inflammation can occur even without an apparent cause.

To prevent the development of complications, early examination and treatment is important.

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