Navigation thread
Navigation thread
Inflamatory Bowel Disease
Make a donation
Make a donation
Joint project with . This link opens in a new tab.

What is Crohn’s disease?

Reading time: 2 min

Crohn’s disease is a chronic illness that differs from ulcerative colitis because it can affect any section of the digestive tract with inflammation occurring in all layers of the intestinal wall. It may affect discontinuous areas, i.e., the digestive tract contains alternating sections of healthy areas and inflamed segments.

As inflammation affects the entire intestinal wall, Crohn’s disease can course with complications such as stenosis (narrowing of the intestinal lumen) and/or fistulas (a connection between two intestinal loops or to an organ, e.g., the urinary bladder) which may be accompanied by collections of pus.

The most frequently affected areas are:

  • Ileum: predominantly the distal ileum
  • Colon: any segment
  • Ileum and colon: both
  • Upper digestive tract: from the mouth to the proximal ileum

Complications associated with Crohn’s disease

The main complications arising in conjunction with Crohn’s disease are:

  • Intestinal obstruction caused by intestinal lumen narrowing secondary to inflammation and/or the accumulation of fibrous scar tissue. The primary symptoms of this complication are abdominal pain (cramps) and general food intolerance (vomiting).
  • Fistulas are abnormal passageways connecting two internal parts of the body. A perianal fistula is a connection between the anal canal and the perianal skin around the end of the anus.

Síntomas más frecuentes de la Enfermedad de Crohn

Standing person with abdominal pain

Dolor abdominal

Person standing with diarrhoea cramps

Diarrhoea

Complications associated with diarrhoea

  • Dehydration: excessive loss of body water
  • Loss of nutrients, water and electrolytes (sodium, potassium, magnesium, etc.)
  • Oral rehydration therapy is essential. Administration of just water is not enough; patients must also receive the correct quantity of electrolytes (oral rehydration solution). In severe cases, fluids must be replaced intravenously.
Physical examination of an abdominal mass

Abdominal pain

Person vomiting in a toilet

Nausea and/or vomiting

Scale with a down arrow indicating a weight loss

Weight loss

Thermometer with a danger signal indicating fever

Fever (a sign of the condition’s severity)

Symptoms may vary depending on the disease’s location. When it affects the small intestine, patients primarily experience abdominal pain, diarrhoea, weight loss and/or loss of appetite. If the disease affects the colon, then the predominant symptom is diarrhoea with or without blood.

Perianal disease

It is important to remember that Crohn’s disease can affect the anus and produce lesions such as:

  • Skin tags: folds of anal mucous membrane protruding outward
  • Fistulas: passageway from inside the rectum to outside the body (perianal skin)
  • Abscess: accumulation of pus due to infection
  • Fissure: small tear appearing as a linear wound in the anal canal
  • Rectal stenosis: narrowing of the anus or rectum because of scar tissue produced by ulcers
Read more Differences between Ulcerative Colitis and Crohn’s Disease
Joint project with . This link opens in a new tab.

Substantiated information by:

Ingrid Ordas Jimenez
Marta Gallego Barrero

Published: 20 February 2018
Updated: 4 September 2020

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.

Subscribe

Receive the latest updates related to this content.

Thank you for subscribing!

If this is the first time you subscribe you will receive a confirmation email, check your inbox

An error occurred and we were unable to send your data, please try again later.

Inflamatory Bowel Disease related news