Surgery for diverticulitis and diverticular disease

Surgery usually isn’t necessary in people who currently have inflamed or infected diverticula (acute diverticulitis). But there are some exceptions. If abscesses (collections of pus) have formed, and treatment with antibiotics isn’t successful, surgery is unavoidable. The aim is then to prevent serious complications such as a perforation (hole) in the wall of the bowel, which can lead to an inflammation of the membrane that surrounds the organs in your belly (peritonitis) and sepsis (blood poisoning).

Even if diverticulitis has been successfully treated with antibiotics, surgery may help to prevent further episodes. This is because about half of all people who have had a larger abscess develop diverticulitis again within a few years – sometimes with serious complications. Surgery is possible about six weeks after the end of the treatment.

Whether or not surgery is a good idea will also depend on whether you have other medical conditions. For example, people who have a weakened immune system or chronic kidney disease are at higher risk of serious diverticulitis-related complications.

Sometimes recurrent inflammation can lead to the formation of fistulas (tunnel-like passageways between two organs) or narrowing of the bowel (intestinal stenosis). Fistulas increase the risk of complications, so surgery to remove them is generally recommended if they arise. Surgery may be recommended for stenosis too, depending on how narrow the bowel has become.

In every other situation, the main aim of treatment is to relieve symptoms in everyday life, such as abdominal pain and digestive problems.

In people who have recurrent diverticulitis that causes ongoing problems, surgery can relieve the symptoms and reduce the risk of further episodes. This is what research in this area suggests. But the surgery hardly affects the risk of diverticulitis-related complications. The reason for this: Research has shown that the risk of complications is highest the first time you have diverticulitis. It is a lot lower when you have further episodes. After the fifth episode, it is less than 1%.

It is not clear what pros and cons surgery has in people who have symptomatic uncomplicated diverticular disease (SUDD). Because of this, surgery is not recommended here. SUDD is characterized by ongoing or recurrent symptoms such as pain, bloating and irregular bowel movements (poop).

The most common type of surgery for diverticular disease is called sigmoid resection (sigmoidectomy). The sigmoid colon is the section of the large intestine that comes just before the rectum, at the end of the bowel. This is the section where the strain of going to the toilet puts the most pressure on the wall of the bowel, so the most diverticula occur there. The surgery involves removing the sigmoid colon and a small area of the rectum. After that, the ends of the bowel are sewn back together again. Because diverticula can also occur in other parts of the bowel, it’s usually not possible to remove all of them.

The surgery is generally done through small cuts in the wall of the belly (laparoscopy). But it is sometimes done through a larger cut in the belly (open surgery).

The bowel has to be completely empty before the procedure. To empty it, you have to drink about 1 liter of a laxative solution and 2 to 3 liters of water the day before surgery. People can have an enema too, which is where liquid is put into the rectum to help cleanse and empty the bowel. This is important so that no stool gets into the abdominal cavity during surgery.

There’s a risk of injury to the bowel or nearby organs during surgery. The surgery may also lead to scarring in the abdominal cavity, which can cause pain or digestive problems.

Another possible risk is known as an anastomotic leak. This is where stitches that were used to sew the two ends of the bowel together come undone again soon after surgery. Bowel contents may then leak into the abdominal cavity, leading to dangerous infections there. Anastomotic leaks occur in about 3 out of 100 people who have this surgery.

Out of every 100 operations, about

• 2 abscesses,
• 4 wound infections and
• 3 episodes of major bleeding

occur too.

And there are the general risks associated with surgery, such as anesthetic-related problems, pneumonia or thrombosis.

Complicated diverticulitis might lead to peritonitis. This is an inflammation of the inner lining of the abdominal cavity (space inside the belly). Pus might then spread inside the cavity, which can result in sepsis (blood poisoning). This is a medical emergency requiring urgent surgery.

To treat peritonitis, the surgeon first rinses out the abdominal cavity and creates a temporary bowel opening (stoma) in the abdominal wall. It usually takes several months for the peritonitis to go away completely. Only then can surgeons do a sigmoid resection. The temporary bowel opening can then be closed again.