Diverticulitis Complications

What Are the Potential Complications of Diverticulitis?

What Are the Potential Complications of Diverticulitis?
Canva (3); Everyday Health
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Updated on November 13, 2024
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Diverticulitis is a condition that occurs when tiny pockets (called diverticula) that have formed in the colon (part of your large intestine) become inflamed. Diverticulitis starts as diverticulosis, which is the development of these pockets over time.

 Diverticulitis is fairly common, especially in older adults — 50 percent of people over the age of 60 have the condition, according to some estimates.

Most people with diverticula don’t have any symptoms. But when the pockets become inflamed or infected, as they do in diverticulitis, symptoms such as abdominal pain, fever, and nausea may develop.

With adequate and prompt treatment, serious complications from diverticulitis are rare.

 But if the condition is left untreated, if the person has an underlying condition, or if the diverticulitis simply doesn’t respond to treatment, some complications can develop.

Below, we review five of the most common complications of diverticulitis, all of which require prompt medical attention.

If you experience any of the signs of diverticulitis complications, such as abdominal pain, an abdomen that feels hard and tense to the touch, fever, or nausea, see a doctor right away.

 Prompt treatment can stave off severe consequences to your health.

Perforation

Diverticulitis causes tiny tears, called perforations, in the bowel walls. The diverticula weaken the colon walls and, if they enlarge, can tear and leak bowel contents into the abdominal cavity. This can lead to infection and inflammation in the abdomen, called peritonitis. Peritonitis is a medical emergency that requires immediate attention, as it can be life-threatening. It’s treated with antibiotics — usually intravenous — or surgery.

Some perforations from diverticulitis can also lead to abscesses, bowel obstructions, and fistulas.

Abscess and Phlegmon

When a pocket in the bowel becomes infected, a phlegmon may form along the bowel wall — a phlegmon is an infected and inflamed area that can spread to the surrounding tissue.

A phlegmon can be treated with antibiotics, but if it isn’t, it can progress into an abscess. An abscess forms along the bowel wall when the pocket inside the bowel becomes infected and fills with pus.

 Abscess symptoms include abdominal pain, fever, and feeling generally unwell (malaise).

 Drainage of abscesses via surgery or with a noninvasive method may be necessary depending on the size of the abscess and response to antibiotics.

Bowel Obstruction

A bowel obstruction is a blockage in the colon. You can have a partial or complete blockage of the large intestine. A bowel obstruction happens when scarring or inflammation makes the colon too narrow for food and liquids to pass. This narrowing process is called stricture formation.

A complete blockage requires emergency surgery while a partial blockage may resolve with nonsurgical treatment and rest. Symptoms of a bowel obstruction include:

  • Severe constipation
  • Bloating
  • Vomiting
  • Abdominal pain and cramps
  • Lack of appetite
  • Feeling generally unwell
  • Diarrhea
  • Signs of dehydration, such as rapid heartbeat and darker-colored urine

If you have symptoms of bowel obstruction, seek medical attention immediately.

Rectal Bleeding

Sometimes, diverticular pouches can damage the blood vessels in the colon wall, resulting in rectal bleeding (also called diverticular bleeding). This often occurs without diverticulitis (infection or inflammation). The main symptom is seeing bright red- or maroon-colored blood in the bowel movements. This occurs in about half the cases. The bleeding is otherwise painless and without any other symptoms.

Most of the time, rectal bleeding stops on its own. But, in severe cases, a hospital stay and further treatment may be required, such as an angiography (blocking off the bleeding artery), colonoscopy, or surgery.

Fistula

A fistula is an abnormal pathway, or connection between two organs, blood vessels, or body parts.

 In diverticulitis, a fistula typically forms when a diverticular abscess extends into a nearby organ. A diverticular fistula occurs in about 4 to 20 percent of diverticulitis cases, and it usually connects the colon with either the bladder, the small intestine, the skin’s surface, the uterus, or the vagina.

Symptoms of a fistula will depend on where it forms and what organs it connects. Symptoms can include:

  • Air bubbles or stool in the urine
  • Pain while urinating
  • Abnormal vaginal discharge (if the fistula affects the vagina)
  • Red and sore skin in the affected area
  • Urinating more often than normal or abnormal urine (if the fistula affects the bladder)

The Takeaway

  • With prompt treatment, diverticulitis complications are rare. But when they do develop, they can be severe and require immediate treatment.
  • Some people may be at a particularly high risk, like older adults and those with a weakened immune system.

  • If you have diverticulitis, see a doctor and return regularly for checkups — especially in the first few days — to make sure any complications are detected early on and prevented or treated promptly.
  • After an episode of diverticulitis, it is important to ensure you have had a recent colonoscopy to rule out the presence of colorectal cancer, which can sometimes be misdiagnosed in an imaging test as diverticulitis.

Common Questions & Answers

What is diverticulitis?
Diverticulitis is a condition that occurs when tiny pockets in the large intestine become inflamed. It starts as diverticulosis, which is the development of these pockets over time. It is a form of colitis.
Risk factors for diverticulitis include age (it's most common in people over 50), genetics, ongoing constipation, a low-fiber diet, obesity, smoking, lack of exercise, and certain medications.
If left untreated, diverticulitis can lead to serious complications such as perforation (tears in the bowel walls), peritonitis (infection and inflammation in the abdomen), abscesses, bowel obstruction, rectal bleeding, and fistulas (abnormal pathways between organs).
Diverticulitis complications are typically treated with antibiotics, fluids, and surgery. The two common types of surgery are bowel or colon resection, where the damaged part of the colon is removed and the healthy ends are reconnected, and bowel resection with a colostomy, where a colostomy bag is temporarily connected to the healthy part of the colon.
Research shows that people with diverticular disease may be at an increased risk of dementia. People with high blood pressure, heart disease, or diabetes may be at a higher risk of experiencing complications from diverticulitis. And it's long been thought that there's a link between diverticulitis and colon cancer, but recent research has called that into question.
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Yuying Luo, MD

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Yuying Luo, MD, is an assistant professor of medicine at Mount Sinai West and Morningside in New York City. She aims to deliver evidence-based, patient-centered, and holistic care for her patients.

Her clinical and research focus includes patients with disorders of gut-brain interaction such as irritable bowel syndrome and functional dyspepsia; patients with lower gastrointestinal motility (constipation) disorders and defecatory and anorectal disorders (such as dyssynergic defecation); and women’s gastrointestinal health.

She graduated from Harvard with a bachelor's degree in molecular and cellular biology and received her MD from the NYU Grossman School of Medicine. She completed her residency in internal medicine at the Icahn School of Medicine at Mount Sinai, where she was also chief resident. She completed her gastroenterology fellowship at Mount Sinai Hospital and was also chief fellow.

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Resources
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