Diverticula are protrusions of the large intestine. If they become inflamed, in the worst case they can burst, threatening intestinal perforation and sepsis. How diverticula form, how inflammation occurs, when surgery is required and what role diet plays.
Irritable bowel disease or celiac disease are among the intestinal diseases that are often discussed. Diverticulum, diverticular disease or diverticulitis, on the other hand, has only received more attention in recent years, although many people are affected. The first German guideline on diverticular disease was only published in 2014.
On average, one-third of the population have diverticula. This prevalence increases significantly with increasing age and the majority of all over 70-year-olds are affected. Around 125,000 patients are treated in hospital every year because of an acute inflammation of these intestinal protuberances, diverticulitis or diverticular disease.
“There is definitely an increase in diverticulitis,” notes Ludger Leifeld. He is chief physician for internal medicine and gastroenterology at the St. Bernward Hospital in Hildesheim. The professor played a key role in the first guidelines and is now revising the “Diverticulitis/Diverticulitis” guidelines with colleagues.
He sees a combination of lifestyle and hereditary factors as the reason why more and more people have diverticulitis. The gastroenterologist reports that diverticula have probably existed for as long as humans have lived on earth. However, it is obvious why there are more people affected than before: it is well known that lifestyle has changed in recent decades, which favors the development of the disease.
Diverticula are protrusions of the lining of the large intestine. “They are not dangerous and most of those affected have no problems with them throughout their lives,” says the scientist, characterizing the harmless diverticulosis. In some cases, however, these sacs can become inflamed, which is when the doctor speaks of diverticular disease or diverticulitis. This inflammation can be acute or chronic.
The intestinal wall consists of mucous membrane and muscle layers. The protuberances develop in weak points of the intestinal mucosa, “where vessels run through the intestinal wall and the muscle layer is therefore thinned out,” the scientist explains in more detail. This gap allows inner layers of mucous membrane to bulge outwards, especially when the connective tissue is weak.
Diverticula form primarily in parts of the lower colon, for example in the sigmoid, the S-shaped section of the intestine, i.e. on the left in the lower abdomen. Because this is where the intestinal contents exert the greatest pressure on the intestinal wall and the risk of protuberances is particularly high.
In addition to a genetic predisposition
encourage the formation of diverticula. But these risk factors also come into play for the development of the inflammation. There are numerous studies that prove this connection, especially for low-fiber diets.
However, the exact cause of the inflammation of the previously harmless diverticula is not yet known. A common hypothesis is that feces are deposited in the protuberances. “The mucous membrane is very thin there, because not all layers have come out through the muscle gaps, only the inner layers,” explains Ludger Leifeld. The smallest injuries, minimal circulatory disorders, then make it possible for germs that normally occur within the intestine to escape to the outside. This leads to inflammation of the surrounding tissue.
Diverticula do not cause any symptoms in a good 80 percent of those affected. However, diverticulitis can develop in the rest, i.e. up to 20 percent. Acute inflammation is manifested by sudden abdominal pain. “In 85 percent of the patients, the pain occurs in the lower left abdomen, in 15 percent in other parts of the abdomen,” explains the expert. There are also digestive problems such as constipation or diarrhea.
In rare cases, bleeding can also occur in connection with diverticula, a symptom of which is visible blood in the stool. Blood in the stool should be checked by a doctor as soon as possible.
The pain that is typical of acute diverticular inflammation is so severe that most of those affected seek medical advice or a clinic’s outpatient department as quickly as possible. But even if the signs are not quite as severe: “Abdominal pain that is new and goes beyond what you know should always be examined by a doctor,” emphasizes the gastroenterologist.
Most diverticula are only discovered by chance, such as a colonoscopy for cancer screening, because the bulges themselves do not cause any symptoms. However, if there are signs such as left-sided abdominal pain, the doctor will examine the colon with an ultrasound after taking a history. Sonography and, if necessary, computed tomography (CT) are the common methods for diagnosing diverticulitis.
In this way, it can be determined what form of intestinal disease it is and the appropriate therapy can be initiated.
The classification of diverticular disease includes four types:
Type 0: asymptomatic diverticulosis, which means diverticula are detectable but do not cause any symptoms, there is no inflammation.
Type 1: acute uncomplicated diverticulitis, divided into a form without a surrounding reaction and one with inflammation of the connective tissue.
Type 2: Acute complicated diverticulitis, where inflammation causes diverticula to rupture. A distinction is made here between covered and open perforation. When the breakthrough is covered, an abscess forms, so the pus encapsulates. The open perforation in diverticulitis means pus and/or stool is leaking into the abdomen.
Type 3: chronic diverticulitis, again subdivided according to whether the inflammation occurs in episodes over years, i.e. keeps recurring, or whether the symptoms persist with or without complications. Complications include fistulas and stenoses. These narrowings occur, for example, when the inflammation heals and scars form.
Type 4: Diverticular hemorrhage
The greatest risk is in acute diverticular disease when there is an open perforation. Then there is a risk of sepsis, i.e. blood poisoning. To prevent this, treatment must start as soon as possible. Incidentally, in connection with the perforation, patients with diverticulosis sometimes fear that the protuberances could burst during a bowel movement. “Diverticula don’t burst when you strain on the toilet,” the gastroenterologist clarifies. However, in the case of diverticula, attention should be paid to soft stools.
One risk of chronic diverticulitis is stenosis, i.e. when the intestine narrows due to scarring. In this way, even an intestinal obstruction can occur, which – like an intestinal perforation – is always a medical emergency and should be treated promptly. The perforation causes very severe pain, so that those affected see no other option than to get to an emergency room as quickly as possible. This massive pain does not always occur with intestinal obstruction, but there is stool retention and sometimes vomiting.
Diverticula themselves do not require treatment as long as they are not causing any symptoms. Therapy is only necessary in the case of inflammation and complications. The treatment of acute uncomplicated diverticulitis, i.e. type 1, can usually be carried out conservatively and on an outpatient basis. “It depends on how good the general condition of the patient is, whether there are other diseases, whether they are immunosuppressed and how old they are,” explains Ludger Leifeld. Risk patients are treated as inpatients.
Therapy includes antibiotics if necessary, liquid food for the first few days and painkillers if necessary. Close medical supervision is important for both outpatient and inpatient treatment. The symptoms usually subside after a few days.
In contrast, acute complicated diverticulitis, i.e. type 2, is usually treated on an inpatient basis and with intravenous administration of antibiotics. If it is covered diverticulitis with complications such as an abscess, this is treated immediately. For larger abscesses, drainage provides relief. In most cases, the condition then improves. If this does not happen and/or the abscess cannot be drained, an operation is required within 72 hours. This surgical intervention is unavoidable in the case of an open perforation and should be carried out promptly immediately after the diagnosis.
In the case of chronic, long-term courses, i.e. type 3 diverticulitis, the operation is not mandatory. Here, the risks of an operation should be weighed against the recurring pain. “This is a case-by-case decision,” says the gastroenterologist. Surgery is also sometimes necessary for fistulas and stenoses that can occur as part of type 3.
Diverticular bleeding, on the other hand, can usually be stopped using the endoscope. However, this is only possible if the source of the bleeding can be found. If this is unsuccessful or if the bleeding is severe, an operation is also performed.
During the operation, the affected part of the intestine is removed, in many cases the sigmoid colon. While in the past the patient usually had to be given a permanent, artificial anus, modern surgical techniques are increasingly making it possible to do without this aid. For example, the two ends in the intestine can be sewn together. However, this is usually not possible with an open perforation. An artificial outlet is created, but often only temporarily, until the surgical suture in the intestine has healed. In a second operation, the executing intestinal stump is then put back.
The prognosis for diverticulitis depends primarily on how young or old and frail the patient is and how severe the disease is. Because the inflammation can come back under certain circumstances. “If the indication is correct, the operation brings most patients back a better quality of life,” summarizes the gastroenterologist.
Anyone who knows that they have bowel protuberances, but there is no inflammation and no symptoms should still make sure that the stool is soft and voluminous. Because constipation and hard stools increase the risk of micro-injuries to the intestinal mucosa and deposits in the diverticula. High-fiber food with lots of fruit and vegetables, possibly psyllium, which is particularly rich in swelling substances, or oat and wheat bran, as well as plenty of fluids and exercise are recommended.
However, if inflammation occurs again and again, i.e. chronic diverticulitis, the following diet is helpful:
But even if the treatment options for diverticulitis have improved, it would be easiest not to develop any diverticula in the first place. However, this can only be partially influenced. “Because the hereditary aspects, such as familial connective tissue weakness, cannot be prevented,” says the gastroenterologist, restricting expectations that are too high. However, everyone can do a lot to keep their intestines healthy if they rely on the high-fiber diet mentioned. Regulated digestion with soft stool minimizes the risks – and can at least slow down the progression of diverticular disease that already exists.
