Colitis: Definition, Types, Causes, Symptoms, Complications, Diagnosis, Treatment and Prevention

It is a condition that reflects inflammation of the colon.

At the level of the colon, there may be diverticula , a type of small swelling of the mucosa, known as diverticulitis .

This localized inflammation of the colon causes pain in the lower left abdomen , as well as other symptoms such as fever.

Types of colitis

Colitis is a very confusing term as it is often used interchangeably as a symptom and a disease.

There are different types and subtypes of colitis that cause further confusion.

Although inflammatory bowel disease is always talked about frequently, but there are other forms of colitis.

Allergic colitis

Allergic colitis occurs only in babies.

In this type of condition, the action of a food protein to which a baby is allergic causes an immune response in the intestines.

Causing irritation that can create ulcerations in the intestines and cause irritability, insufficient feeding, excessive gas production, diarrhea and even the presence of blood in the stool.

The most common food that causes allergic colitis is milk.

Fortunately, allergic colitis is a type of colitis that is easy to treat by avoiding the food that causes the reaction.

Microscopic colitis

Microscopic colitis owes its name to the need to examine the tissue with the help of a microscope to make the diagnosis accurately.

There are two types of microscopic colitis, collagenous colitis and lymphocytic colitis.

When it comes to collagenous colitis, the main feature is the formation of a thick layer of collagen in the colon tissue that causes painful symptoms.

In lymphocytic colitis, white blood cells known as lymphocytes form in the intestinal tissue.

Both forms of microscopic colitis are believed to be autoimmune and treatment is similar to that recommended for inflammatory bowel disease.

Infectious colitis

Infectious colitis occurs when a virus, bacteria, or parasite invades the intestines.

These infections occur due to the consumption of contaminated food or water.

Symptoms that occur with infectious colitis include: diarrhea, abdominal cramps, and dehydration due to numerous watery stools.

This type of colitis disappears when the infection caused by the pathogens resolves.

Ischemic colitis

Ischemic colitis occurs when there is no blood supply to a portion of the colon.

This loss of blood flow causes inflammation of the tissue.

Symptoms seen in ischemic colitis include: pain, fever, and diarrhea.

This form of colitis can be caused by variations in blood pressure, smoking, diabetes, high cholesterol levels, intestinal obstructions or even hernias.

Treatment for ischemic colitis is aimed at eliminating or limiting the risk factor causing the condition and treating pain or dehydration.

Causes of colitis

Some factors related to the presence of colitis include:

  • Infections caused by a virus or parasite.
  • Food poisoning due to bacteria.
  • The Crohn ‘s disease .
  • A lack of blood flow (ischemic colitis).
  • Radiation applied to the large intestine, called radiation stenosis.
  • Necrotizing enterocolitis in newborns.
  • Pseudomembranous colitis caused by Clostridia difficile infection.

There are some conditions that are often called “colitis” but have different underlying causes that make them classifiable as contagious or non-contagious.

Some terms related to subsets of colitis, like the term “colitis,” have multiple causes that make these conditions contagious or non-contagious:

  • Enteritis: contagious and not contagious.
  • Proctitis: contagious and not contagious.
  • Inflammatory bowel disease: subsets.
  • Crohn’s disease: not contagious.
  • Ulcerative colitis: not contagious.
  • Indeterminate colitis: not known.
  • Allergic colitis: not contagious.
  • Pseudomembranous colitis: contagious.
  • Infectious colitis (many bacterial, viral, fungal, and parasitic types) – Most are contagious, but some are not contagious.
  • Ischemic colitis: not contagious.
  • Immunodeficiency disorders (many types): not contagious.
  • Necrotizing enterocolitis: not contagious.
  • Microscopic colitis: not contagious.
  • Colitis por C. difficile: contagious.
  • Bacterial colitis: contagious.

Contagious types of colitis are spread from person to person and are usually spread by direct contact with the hands (fecal fluids and oral fluids).

But others can be transmitted through contaminated food or fluids, and for some types, indirectly through contact with contaminated items such as clothing, utensils, or toothbrushes.

Symptoms of colitis

The main manifestations of acute colitis are episodes of diarrhea and abdominal pain.

In some cases, acute colitis can be more serious: it is suspected in case of diarrhea with the presence of blood containing mucus, fever and an altered general condition.

Although chronic colitis manifests itself by abdominal pain and diarrhea. But digestive bleeding, fatigue, and weight loss can also occur, as well as symptoms of chronic inflammatory disease including cracks and ulcerations around the anus from Crohn’s disease.

If a person has diarrhea that does not resolve within a few days, blood in the stool, increased abdominal discomfort or pain, or early signs of dehydration, they should urgently seek medical attention.

These diarrhea can cause dehydration. Symptoms of dehydration include:

  • Low or no urine output (decreased urination).
  • Presence of bloody diarrhea.
  • Presence of tarry stools
  • Severe abdominal pain
  • Constant nausea and vomiting.

Complications of colitis

Complications of colitis can include:

  • Bleeding accompanying bowel movements.
  • Perforation of the colon.
  • Toxic megacolon.
  • Ulceration


The healthcare provider will take a medical history accompanied by a physical exam.

In the medical history, factors such as: the time you have been presenting the symptoms, the degree, frequency and duration of pain, the frequency of diarrhea, recent trips, treatment with antibiotics, among others, will be taken into account.

It can be diagnosed by inserting an endoscope into the rectum called a flexible sigmoidoscopy or colonoscope to view certain areas of the colon.

The main test to diagnose colitis is colonoscopy, especially when the disease has been ongoing for several weeks or is accompanied by more severe manifestations.

During this scan, it is common practice to perform a biopsy (that is, a harvesting of the lining of the colon) which, after analysis, will determine the source of the inflammation.

Biopsies that can show changes related to inflammation. This can help determine the cause of the colitis.

Other tests that can identify colitis include:

  • CT scan of the abdomen.
  • Magnetic resonance imaging of the abdomen.
  • Barium enema.
  • Stool culture.
  • Stool test for eggs and parasites.

The diagnosis of colitis is based on the symptoms described by the patient and the results of medical tests.


Treatment for colitis is determined when the cause is diagnosed.

In case of chronic colitis associated with Crohn’s disease, corticosteroids and salicylated derivatives will be prescribed.

Some immunosuppressants can also be used. In cases of ulcerative colitis.

With some variations, the same treatments are used.

In the case of acute colitis, the administration of drugs that fight infectious agents (antibiotics, antiparasitics among others) is often effective.

In chronic colitis caused by an autoimmune condition, treatment relies on the use of corticosteroids and medications to reduce or reduce the body’s immune response.

Some types of colitis, such as Crohn’s disease or microscopic colitis, have no known cure to date; others, such as enteritis caused by bacteria, can be “cured,” often with the use of certain antibiotics.

The doctor should first discuss the type of colitis you have (just say that the colitis is not specific enough for a doctor’s diagnosis), and then discuss your treatment and the possible ‘cure’, if any, for the specific type of colitis.

Homeopathy, herbal medicine, aromatherapy, and naturopathy can be effective in addition to the proper treatment of colitis.


The main prevention tips that reduce the number and intensity of colitis attacks are to limit the consumption of spicy dishes and spices in general, such as mustard or curry, fried foods, raw vegetables, dried beans, beans and lentils, cabbages, foods with excess fat, coffee, tea, drinks like soda, and alcohol.

You should chew your food well, eat on a fixed schedule, avoid irritating medications such as laxatives, and as in many diseases, avoid stress.

In Crohn’s disease, quitting smoking appears to be beneficial, as is a fiber-free diet.