Reviewed by Minesh Khatri, MD on October 28, 2019

What Is Diverticulitis?


Diverticulitis is the infection or inflammation of pouches that can form in your intestines. These pouches are called diverticula.

The pouches generally aren’t harmful. They can show up anywhere in your intestines. If you have them, it's called diverticulosis. If they become infected or inflamed, you have diverticulitis.

Sometimes, diverticulitis is minor. But it can also be severe, with a massive infection or perforation (your doctor will call it a rupture) of the bowel.

Symptoms of Diverticulitis

You can have the pouches and not know it. The diverticula are usually painless and cause few symptoms, if any. But you might notice:

  • Cramping on the left side of your abdomen that goes away after you pass gas or have a bowel movement
  • Bright red blood in your poop

Diverticulitis symptoms are more noticeable and include severe abdominal pain and fever.

Diverticulitis can be acute or chronic. With the acute form, you may have one or more severe attacks of infection and inflammation. In chronic diverticulitis, inflammation and infection may go down but never clear up completely. Over time, the inflammation can lead to a bowel obstruction, which may cause constipation, thin stools, diarrhea, bloating, and belly pain. If the obstruction continues, abdominal pain and tenderness will increase, and you may feel sick to your stomach or throw up.

Causes of Diverticulitis

The pouches on your intestines get inflamed or infected when they tear or become blocked by poop.

Your chances of getting diverticulitis rise with age. It’s more common in people over 40. Other risk factors include:

  • Being overweight
  • Smoking cigarettes
  • Not getting enough exercise
  • Eating lots of fat and red meat but not much fiber
  • Taking certain kinds of drugs, including steroids, opioids, and nonsteroidal anti-inflammatories like ibuprofen or naproxen

Complications of Diverticulitis

If you don’t treat it, diverticulitis can lead to serious complications that require surgery:

  • Abscesses, collections of pus from the infection, may form around the infected diverticula. If these go through the intestinal wall, you could get peritonitis. This infection can be fatal. You’ll need treatment right away.
  • Perforation or tearing in the intestinal wall can lead to abscesses and infection because of waste leaking into the abdominal cavity.
  • Scarring can lead to a stricture or blockage of the intestine.
  • Fistulas can develop if an infected diverticulum reaches a nearby organ and forms a connection. This most often happens between the large intestine and the bladder. It can lead to a kidney infection. Fistulas can also form between the large intestine and either the skin or the vagina.

If you have severe bleeding, you may need a blood transfusion.

Diverticulitis Diagnosis

The symptoms of diverticulitis can also look like other problems. Your doctor will narrow things down by ruling out other issues. They’ll start with a physical exam. Women may get a pelvic exam, too. Your doctor may then order one or more tests, including:

  • Blood, urine, and stool tests to look for infection
  • CT scans to look for inflamed or infected diverticula
  • A liver enzyme test to rule out liver problems

Diverticulitis Treatment

If your diverticulitis is mild, your doctor will suggest rest and a liquid diet while your intestines heal. They might also give you antibiotics to treat the infection.

In more severe cases, you might need to stay in the hospital and take antibiotics that are intravenous (injected into your veins). If you have an abdominal abscess, your doctor will drain it. If your intestine is ruptured or you have peritonitis, you’ll need surgery.

When you’re healed, your doctor might give you a colonoscopy to rule out colon cancer.

You can prevent diverticulosis and diverticulitis and their complications by eating plenty of fiber, drinking lots of water, and exercising regularly.

WebMD Medical Reference



National Digestive Disease Information Clearinghouse. 

Cleveland Clinic: “Diverticular Disease.”

Mayo Clinic: “Diverticulitis,” “CT scan.”

Merck Manual Consumer Version: “Diverticulitis.”

TeensHealth/Nemours: “Abscess.”

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