Inflammatory bowel disease
What is Inflammatory Bowel Disease?
Inflammatory Bowel Disease (IBD) is a chronic disease of unknown cause in which inflammation of the colon and/or small intestine occurs and occurs in flare-ups. It encompasses two entities, ulcerative colitis, and Crohn's disease. It usually affects young people between 20 and 30, although it is also diagnosed in older people.
The symptomatic episodes of this chronic disease alternate with remission episodes in which the symptoms disappear after appropriate treatment. The frequency and severity of outbreaks are highly variable and unpredictable, although 50% of patients present mild symptoms and are asymptomatic most of the time.
The digestive system comprises a set of organs responsible for carrying out the process of digestion.
Its function is to transport food, digest it through digestive juices, absorb its nutrients and expel it through defecation.
The digestive tube measures about 11 meters from the mouth to the anus and comprises the esophagus, stomach, small intestine, and large intestine (the colon).
The small intestine measures 6 and 7 meters and includes the duodenum, jejunum, and ileum, which absorb nutrients from already digested food. The small intestine begins at the duodenum and ends at the ileocecal valve, which joins the large intestine.
The large intestine, also called the colon, is between 1.20 and 1.60 m long, and its primary function is to absorb water from digested food to form more solid feces.
Th colon is divided into several segments: the cecum, ascending colon (or right colon), transverse colon, descending colon (or left colon), sigma, and rectum. From the cecum to the rectum, the colon forms a series of curves that form the colic framework.When the colon is inflamed, it loses its absorption capacity, which translates into less consistent stools (pasty or liquid). If the inflammation is severe, there may be traces of blood in the stool.
How many people does Inflammatory Bowel Disease affect?
Inflammatory bowel disease (IBD) is more frequent in developed countries and the Caucasian population. It affects men and women equally. It can appear at any age, although it is more common to be diagnosed between 20-30, with a second peak of incidence from 50 to 70.
In Spain, for every 100,000 inhabitants, it is estimated that there are 87-110 people affected by inflammatory bowel disease.
Causes and risk factors of Inflammatory Bowel Disease
Although the exact cause of the disease is unknown, it is known that different factors are involved in its development:
It is not a hereditary disease but appears in people with a genetic predisposition. The interaction with different environmental factors (infections, smoking, etc.) triggers an abnormal immune response maintained over time.
Gut microbiota bacteria in a petri dish
Various germs have been linked to the development of inflammatory bowel disease, but none have been confirmed as the origin. Instead, it is believed that the antigens (substances that give rise to the immune response) found in the intestinal lumen generate inflammation in the intestine.
Can it affect other parts of the body?
Some patients have affected body parts that are unrelated to the digestive tract. These manifestations can take the form of joint pain (arthritis), skin lesions, eye inflammation (uveitis), mouth ulcers, liver disease, and gallstones or kidney stones, among others. Some of these problems usually improve when the symptoms of the disease subside, although sometimes they require specific medication.
What is ulcerative colitis?
Ulcerative colitis is a chronic inflammatory disease that exclusively affects the most superficial layer of the colon. Therefore, the severity and extent of the inflammation vary in each patient.
The areas that may be affected are:
Proctitis. The affected area is limited to the rectum.
Proctosigmoiditis. Affectation of the rectum and sigma.
Left colitis or distal ulcerative colitis. Involvement is limited to the left colon (up to the splenic flexure).
Pancolitis. Involvement that extends beyond the splenic flexure.
Most frequent symptoms of Ulcerative Colitis
Stools with mucus and/or blood (rectal bleeding)
Small and numerous stools
Frequent desire to evacuate and defecation urgency
Nocturnal bowel movements
They indicate seriousness: fever, abdominal pain, and the affectation of the general state with fatigue, loss of appetite, and weight.
Ulcerative Colitis Complications
Toxic megacolon is a severe complication in which the colon is dilated to more than 6-7 cm in diameter, which can even lead to perforation. It is rare since medical treatment is rapidly intensified in severe ulcerative colitis that does not respond to conventional treatment.
The signs that should alert of this complication are fever, tachycardia, distension, and intense abdominal pain.
A simple abdominal X-ray is required for its diagnosis.
Treatment of Inflammatory Bowel Disease
Inflammatory bowel disease is chronic, and no curative treatment has been discovered. However, a wide range of drugs allows adequate control of symptoms that improve patients' quality of life.
The treatment of inflammatory bowel disease is complex and highly variable from one patient to another, which requires a highly individualized approach. The patient's symptoms and the tests' results serve as a guide when prescribing one treatment or another.
The objective of the treatment is to eliminate the symptoms and restore the patient's quality of life by healing the lesions that cause intestinal inflammation, thus avoiding the progression of the disease and its possible complications.
Throughout the evolutionary course of inflammatory bowel disease, there are episodes of inflammatory activity, called “flare-ups,” and periods in which the patient is asymptomatic, known as “remission.”
There are two types of treatment, the one used to control the symptoms in outbreaks of activity so that the symptoms disappear and avoid complications, and the maintenance treatment to keep the disease inactive and prevent the reappearance of symptoms.
What are the available treatments?
The treatment choice depends on the type of disease (ulcerative colitis or Crohn's disease), location, degree of inflammatory activity (mild, moderate, severe), age, previous course of the illness, previous response to medications, and patient needs. For this reason, the choice of treatment must be personalized.
Available treatments for inflammatory bowel disease include:
Salicylates are anti-inflammatory drugs with a local mechanism of action on the colon. They are not immunosuppressive, so they don't decrease defenses and are very safe. They can be administered orally or rectally as a suppository, foam, or enema. They are used for maintenance treatment or flare-ups in ulcerative colitis. However, they have not proven to be effective for Crohn's disease.
Corticosteroids. They are drugs with anti-inflammatory and immunosuppressive effects. They are used in moderate and severe disease outbreaks and are limited exclusively to outbreaks of activity since they have many side effects if used for long periods. For this reason, they should never be taken for the maintenance of remission.
Immunosuppressants. They modulate the exaggerated response of the immune system and reduce inflammation. They are used in those patients who do not respond to corticosteroids. They are effective in keeping the disease inactive without the need to take corticosteroids.
Biological therapy. The better knowledge of inflammatory bowel disease has contributed to the development of new treatments, which act on different immunological and inflammatory factors involved in regulating and maintaining the condition.
Biological therapy is used when conventional treatments, such as corticosteroids and immunosuppressants, have failed. However, in certain circumstances (cases of severe diseases already at diagnosis), they can be used as first-line treatment.
clinical trials. Clinical trials are medical research studies that evaluate drugs in development with different mechanisms of action than those already approved by regulatory agencies. Clinical trials are necessary to obtain new therapeutic options and advance knowledge of new drug therapies.
Surgery. Surgery is indicated when medical treatment fails. It is usually performed by laparoscopy, a minimally invasive surgical technique that allows quick recovery with a lower risk of complications.