Diverticula are outward projections of the wall of a hollow organ. They can occur throughout the digestive tract. Most often, however, diverticula develop in the colon on the left-hand side. The urinary tract (ureter, urethra, bladder) and, in very rare cases, the heart can also be affected.
Depending on whether all or only some wall layers protrude, a distinction is made between
- True diverticula (all wall layers bulge out) and
- False diverticula, also called pseudodiverticula (usually only the mucosa lining the intestine and the underlying submucosa are involved).
Most cases of diverticula are pseudodiverticula. This article therefore refers primarily to pseudodiverticula.
The term diverticulosis is defined by the presence of usually multiple diverticula. Diverticular disease is when the diverticula cause symptoms. If one or more diverticula are inflamed, the diagnosis is diverticulitis.
The presence of diverticula in the intestine and their expression can be divided into different classes. They are important for the therapeutic approach.
If the diverticula are not inflamed, the condition is type 0, asymptomatic diverticulosis. Inflamed diverticula or diverticulitis can be divided into types 1 to 4.
Diverticula in the intestinal wall can cause inflammation and the intestine can even rupture © Henrie | AdobeStock
The appearance of diverticula does not usually have any pathological significance. It only becomes problematic when symptoms or complications occur. Seventy percent of people who have diverticula remain asymptomatic for life.
In the remaining 30 percent, various symptoms may develop depending on the stage of the disease:
- Flatulence, distended abdomen, the feeling of an incomplete bowel movement, although these symptoms may usually improve after defecation,
- Altered stool consistency (primarily constipation),
- Altered stool frequency,
- Sometimes severe intestinal bleeding (diverticular bleeding is the most common cause of bleeding from the gastrointestinal tract),
- Pain in the lower left abdomen to extreme abdominal pain, and
- A palpable cylindrical firm structure up to a rigid abdomen.
A doctor must be consulted quickly, especially if there are signs of acute diverticular disease. Signs include left lower abdominal pain and hardening of the abdomen.
The cause of this pain is the spread of the inflammation to the outside of the intestine and to the peritoneum. This causes peritonitis (inflammation of the peritoneum).
As diverticular disease progresses, it may lead to
- The accumulation of pus (abscesses) through to
- Perforation (tearing) of the intestine.
This allows excrement and air to pass from the intestine into the abdominal cavity. Despite surgical treatment and antibiotic therapy, this "fecal peritonitis" can lead to death.
If inflammation (even mild inflammation) occurs repeatedly, this is referred to as chronic diverticular disease. As a result, shrinkage of the intestine and the development of a narrowing (stenosis) in the intestine may occur as the disease progresses.
Diverticula develop with increasing age. While only about ten percent of people under the age of 50 have diverticula, one in two 80-year-olds already has intestinal bulges.
In addition, there is evidence that some dietary habits may contribute to the development of diverticula: Populations with traditionally more fiber-rich diets have significantly fewer diverticula than populations in industrialized countries, which more often have low-fiber diets.
This results in the theory that diverticula are caused by a diet low in fiber. A low-fiber diet, combined with drinking less water, causes the intestines to process less stool. As a result, the interior of the intestine (intestinal lumen) is less filled.
The intestine moves spontaneously, i.e., without conscious human influence. These bowel movements are controlled by the intestine filling or the intestinal wall being correspondingly stretched. With less intestinal content, spontaneous motility decreases. A much higher pressure must then be applied for the corresponding waves of movement, which can lead to the bulges.
Risk factors for the development of diverticula are therefore a low-fiber diet and a resulting risk of constipation. Low physical activity and obesity can also increase the likelihood of developing diverticula.
On the other hand, risk factors of diverticular disease and diverticulitis are mainly
Most diverticula do not cause symptoms. Therefore, asymptomatic diverticula are usually found incidentally during a medical check-up or while diagnosing another disease. Only after symptoms occur can a targeted search for their cause be carried out.
The basis of every medical diagnosis is discussing the patient’s medical history (anamnesis). Here, the doctor asks the patient about
- The nature and severity of the symptoms,
- Past diseases,
- Medications taken, and
- Familial diseases.
In the subsequent physical exam, the abdomen is palpated and listened to. The doctor takes the body temperature and performs a digital rectal examination (examination of the rectum with a finger). In most cases, a blood test is also performed. In the laboratory, leukocyte and CRP levels are tested. CRP means C-reactive protein, a value that usually rises when inflammation is present.
In the field of imaging diagnostics, ultrasounds and computed tomography scans are mainly carried out. In diverticular disease, there is a risk that the endoscope will perforate (tear) the intestine. Therefore, a colonoscopy should not be performed in the acute phase.
A colonoscopy is only performed in cases of intestinal bleeding from diverticula to look for the source of bleeding and to stop the bleeding if possible. If no source of bleeding can be identified, further imaging examinations (CT angiography, angiography, or scintigraphy) are necessary.
If mild and nonspecific symptoms persist for more than three to six months, a colonoscopy should be performed. This allows the doctor to safely rule out other intestinal diseases as the cause.
For treatment, it is important to confirm the diagnosis and exclude other causes. Therapy is always stage-dependent.
People with diverticula should
- Engage in regular physical activities,
- Maintain/achieve normal weight, and
- Eat a high-fiber, vegetarian diet.
These measures can prevent diverticulitis.
Mild symptoms, such as irregular bowel movements, can often be successfully treated by regulating bowel movements. A high-fiber diet is usually recommended for this purpose.
If the tendency towards constipation continues to persist, additional administrations of
- Swelling agents (wheat bran, ground flaxseed) and
- Dairy products (e.g., natural yogurt)
are worth recommending. If these measures do not bring about an improvement in the symptoms, the doctor can prescribe stool-regulating medication (do not self-medicate!).
Depending on the severity of the disease, treatment ranges from
- Regulating bowel movements through a high-fiber diet, to
- Antibiotic therapy, and
- Surgical removal of sections of the large intestine containing diverticula, including
- Stopping diverticular bleeding and
- Emergency surgery for intestinal perforation.