Diverticulosis is a disease in which lumps (protuberances) form in the intestinal wall. For most people, these lumps do not cause discomfort, so no treatment is required. In some cases, though, severe abdominal pain, stool irregularities, or inflammation may occur. This inflammation is known as diverticulitis.
What is diverticulosis?
If the wall of a hollow organ, such as the intestine, protrudes outwards, doctors refer to this as a diverticulum. The wall of the intestine consists of several layers (from inside to outside):
- Mucous membrane that comes into direct contact with chewed food (the bolus),
- Connective tissue that provides stability to the intestine, and
- Muscles responsible for intestinal movement (motility).
Depending on how many layers are affected by the lump, one speaks of true diverticula or false diverticula (pseudodiverticula).
- True diverticula: A true diverticulum is when all wall layers protrude together.
- False diverticulum: A false diverticulum is a protuberance that affects only single wall layers. Mostly it is the mucous membrane and the directly adjacent connective tissue.
Diverticulosis involves a false diverticulum because only the mucous membrane of the intestinal wall protrudes through muscle in the intestine.
When several diverticula occur, it is called diverticulosis. This does not yet have pathological significance. It is only when these diverticula cause symptoms or complications that so-called diverticular disease is present.
When diverticula can become inflamed, physicians describe the emerging disease as diverticulitis (the ending “-itis” is the medical term for inflammation).
How does diverticulosis occur?
Lumps in the intestine occur through the combination of various factors:
A major role is played by the pressure that occurs inside the intestine, called intestinal pressure (intraluminal pressure). It is believed that a healthy diet is important to maintain optimal intestinal pressure. For example, a low-fiber diet can increase the pressure in the intestine. Due to increasing pressure, a weakening of the intestinal wall and thus the formation of diverticula may occur.
Natural weak spots of the intestinal wall
Another factor contributing to diverticulum formation are so-called natural weak spots in the intestinal wall. These are usually parts of the intestinal wall through which blood vessels enter. At these points, the muscle layer is thinner than in the other intestine and lumps can emerge more easily.
In the Western, diverticula are predominantly formed in the left-sided part of the colon, which is called the sigmoid (sigma or s-shaped) due to its shape. In this part of the intestine, there are many blood vessels, which promotes natural weak spots in the intestinal wall. In addition, significant pressure occurs here, as this part of the intestine is heavily stressed, among other things, by “pressing” when going to the toilet. Because constipation often leads to pressing, the risk of developing diverticula is increased.
Are lumps in the intestine dangerous?
Most diverticula cause no discomfort and are discovered only by chance, for example, as part of a colonoscopy. Only in about a quarter of those affected does diverticulosis lead to symptoms and complications. The main dangers of diverticula are as follows:
Diverticular disease (symptomatic diverticular disease) is characterized by pain in the lower abdomen and irregular bowel movements (both constipation and diarrhea). Doctors suspect that diverticula impede the mobility of the intestine (motility) and cause a reduced pain threshold in the intestine. A consequence of diverticular disease is then a motility disorder and increased sensitivity (hypersensitivity) of the intestine.
There is a risk of one or more diverticula becoming infected. This disease, called diverticulitis, causes severe pain in the lower abdomen. This is most often more strongly pronounced on the left side. In case of an atypical situation of the affected intestinal section, however, it can also cause pain located on the right side or in the middle of the lower abdomen. The pain starts suddenly and rapidly increases in intensity. In addition, there are changes in bowel regularity, and generalized disease symptoms such as fever, nausea, and vomiting.
So-called diverticular bleeding occurs in about five percent of patients with diverticula. The blood that escapes from the diverticulum is often noticed by the affected person during bowel movements. Most of the time, diverticular bleeding is benign and regulates itself. In cases where the bleeding lasts, it may be necessary to stop the flow of blood (hemostasis) as part of a colonoscopy. If there is blood in the stool, other dangerous causes such as colon cancer should also be checked.
Are there links between diverticulosis and IBS?
Symptoms of symptomatic diverticular disease are very similar to those of irritable bowel syndrome. While diverticulitis (the inflammation of a diverticulum) is a distinct and clearly distinguishable disease, there is disagreement among medical professionals as to whether symptomatic diverticular disease and IBS are different diseases at all. Some physicians believe symptomatic diverticular disease is only diagnosed in patients who have diverticula in their intestines but who actually have IBS. They see the diverticula more as a chance finding that has nothing to do causally with IBS symptoms.
One difference among the two diseases is that IBS sufferers either tend to have diarrhea or constipation, whereas people with diverticular disease are more likely to complain of diarrhea. Irritable bowel patients also often experience relief after their bowel movements, which patients with diverticula do not describe. The latter also more often complain of pain lasting more than 24 hours.
There is some evidence that inflammation of diverticula can cause irritable bowel syndrome. This phenomenon is referred to as “post-diverticulitis IBS”, i.e. “irritable bowel syndrome after diverticulitis.”
How does the doctor diagnose diverticulosis?
Since diverticula usually cause no discomfort, the diagnosis often occurs by chance. The lumps might be noticed, for example, in a colonoscopy, which is recommended for everyone by the age of 55 for colorectal cancer screening.
For diverticula that cause discomfort, the medical history gives the doctor important information for the presence of the disease. The suspicion can then be confirmed by means of an X-ray examination or a colonoscopy.
How can you treat diverticulosis?
The treatment can be divided into three main areas: No symptoms, symptoms, and inflammation.
Diverticulosis without symptoms
As long as the diverticulosis remains without symptoms, there is no reason for treatment. To prevent inflammation of the diverticulum (diverticulitis), medical specialists recommend a vegetarian and high-fiber diet. The dietary fiber contained in fruits and vegetables are more likely to be recommended in terms of their preventive effect than fiber from cereals.
Symptomatic diverticular disease
With symptomatic diverticular disease, a fiber-rich diet may be useful. However, at present it is not clearly proven that dietary fiber can actually improve symptoms with symptomatic diverticular disease.
Since relationships between symptomatic diverticular disease and IBS have been described, it may help to identify and eliminate potential IBS triggers. In addition, you can keep a food diary to track possible food intolerances.
Inflamed diverticula (diverticulitis) are usually treated with antibiotics in tablet form. In addition, patients are advised to take only liquid or light food until symptoms improve. If the diverticulitis is treated with antibiotics, it should improve after 2-3 days.
In particularly severe cases, it may happen that the inflamed diverticulum must be removed via surgery in order to prevent the spread of the inflammation.
Diverticulosis is a disease that is usually harmless. However, it can lead to discomfort such as pain in the lower left abdomen. If such symptoms occur, it is advisable to consult a doctor to initiate a rapid treatment of the disease and to exclude other diseases with similar symptoms.
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