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Pope Francis's Diverticular Disease

— A look at the pontiff's recent medical condition

MedpageToday
A photo of Pope Francis

Pope Francis resumed his weekly appearances from a Vatican window to bless the faithful 2 weeks after undergoing surgery on July 4. The pontiff had nearly half of his colon removed due to severe narrowing of the large intestine.

"His Holiness Pope Francis was taken to A. Gemelli Policlinic in Rome where he [underwent] a scheduled surgery for a symptomatic diverticular stenosis of the colon," said Matteo Bruni, director of the Holy See Press Office.

This surgery was Pope Francis's first significant health issue since he became pope 8 years ago. He rarely misses scheduled events except when suffering from recurrent episodes of sciatica or an occasional cold. The only other significant surgery the pope has undergone was when he had part of a lung removed at the age of 21 due to a pulmonary infection.

Diverticulosis

Diverticulosis is a condition that occurs when small pouches, or sacs, form and push outward through weak spots in the wall of the colon. They are most common in the sigmoid colon.

When diverticulosis causes symptoms or problems, it is called diverticular disease. Symptoms include changes in bowel movement patterns or pain in the abdomen. Diverticulosis may also cause diverticular bleeding and diverticulitis.

The prevalence of diverticulosis is highest in the Western world and in countries that follow a more Western lifestyle. It is quite common, especially as people age. Research has suggested that about 35% of U.S. adults ages 50 and younger and about 58% of those older than 60 have diverticulosis. Most people with diverticulosis will never develop symptoms or problems.

Experts used to think that 10% to 25% of people with diverticulosis would develop diverticulitis. However, more recent research has suggested that the percentage who develop diverticulitis may be much lower -- less than 5%.

In the U.S., about 200,000 people are hospitalized for diverticulitis each year, and about 70,000 people are hospitalized for diverticular bleeding each year.

Acute diverticulitis (e.g., inflammation, infection, or perforation) is typically suspected when a patient presents with lower abdominal pain (particularly on the left side). Patients may additionally present with abdominal tenderness to palpation and an elevated white blood cell count. An abdominal CT scan will help differentiate between complicated versus uncomplicated disease in this case.

Pathophysiology

First, a bit of review on colonic anatomy -- in particular, the teniae coli. Unlike the small intestine and rectum, the colon contains only one complete muscular layer, the inner circular layer. The outer longitudinal layer is concentrated in the three teniae coli.

The teniae coli -- the mesocolic, free, and omental teniae coli -- are three separate longitudinal ribbons (taeniae meaning "ribbon" in Latin) of smooth muscle on the outside of the ascending, transverse, descending, and sigmoid colon. The teniae coli contract length-wise to produce the haustra, the bulges in the colon. The bands converge at the root of the vermiform appendix and at the rectum.

The pathogenesis of diverticular disease is believed to involve structural abnormalities of the colonic wall and disordered intestinal motility.

Structural abnormalities

Spaces between the circular bands of teniae coli are weak points in the bowel and are the most common sites of diverticulosis. According to , microscopic studies have revealed muscle atrophy at these sites, which are naturally susceptible to herniation. In addition, compared with healthy controls, those with diverticulosis show marked thickening of the circular muscle, shortening of the tenia, and narrowing of the lumen. The thickening of the muscle is not due to hypertrophy, but rather to abnormal elastin deposition. This results in a shortening of the muscle layer and an accordion-like folding effect called concertina, particularly where diverticula are prominent.

Colonic motility issues

Colonic motility issues include exaggerated segmental muscle contractions, elevated intraluminal pressures, and separation of the colonic lumen into chambers. "The increased incidence of diverticula in the sigmoid colon is explained by Laplace's law, such that pressure is proportional to wall tension and inversely proportional to bowel radius. As the sigmoid colon is the colon segment with the smallest diameter, it is also the segment with the highest intraluminal pressures," according to .

Other factors

For more than 50 years, experts thought that following a low-fiber diet led to diverticulosis. However, recent research has found that a low-fiber diet may not play a role. One study also found that a high-fiber diet with more frequent bowel movements may be linked to a greater chance of developing diverticulosis.

Some studies have suggested that genetics may play a role in the development of diverticulosis and diverticulitis. Other factors that may also play a role include certain medications, including nonsteroidal anti-inflammatory drugs and steroids; lack of exercise; obesity; and smoking.

Symptoms

Most patients with diverticulosis do not have any symptoms, and the condition itself is not dangerous. However, some patients may experience unexplained abdominal pain or cramping, alterations in bowel habits (constipation or diarrhea), or blood in the stool. Any bleeding associated with diverticulosis is painless. A diagnosis of diverticulosis is suspected when a patient presents with any of these symptoms.

Complications of Diverticulitis

Diverticulitis can come on suddenly and can cause other problems, such as:

  • Abscesses -- painful, swollen, infected, and pus-filled areas just outside the colon wall that can present with nausea, vomiting, fever, and severe abdominal tenderness. Abscesses can be treated with antibiotics, but may require drainage if unresponsive.
  • Perforations -- small tears or holes in a pouch in the colon.
  • Peritonitis -- inflammation or infection of the lining of the abdomen. Pus and stool that leak through a perforation can cause peritonitis.
  • Fistula -- an abnormal passage, or tunnel, between two organs or between an organ and the outside of the body. The most common types of fistula with diverticulitis occur between the colon and the bladder or between the colon and the vagina in women.
  • Intestinal obstruction -- a partial or total blockage of the movement of food or stool through your intestines.

Treatment

The goal of treating diverticulosis is to prevent the pouches from causing symptoms or problems.

High-fiber diet

Although a high-fiber diet may not prevent diverticulosis, it may help prevent symptoms or problems in people who already have diverticulosis. A healthcare provider may suggest an increase of dietary fiber. This should be done slowly to reduce the chances of having abdominal gas and pain.

Fiber supplements

A healthcare provider may suggest taking a fiber product such as methylcellulose (Citrucel) or psyllium (Metamucil) one to three times a day. These products are available as powders, pills, or wafers, and provide 0.5 to 3.5 grams of fiber per dose. Fiber products should be taken with at least 8 ounces of water.

Medications

Some studies have suggested that (Asacol) taken every day or in cycles may help reduce symptoms that may occur with diverticulosis, such as pain in the abdomen or bloating. Other studies have suggested that the (Xifaxan) may also help with diverticulosis symptoms.

Probiotics

Some studies have shown that may help with diverticulosis symptoms and may help prevent diverticulitis. Probiotics are live microorganisms that are intended to have health benefits when consumed. They can be found in yogurt and other fermented foods and dietary supplements. They may be helpful by modifying gut microbial balance and have anti-inflammatory effects. The use of probiotics in diverticular disease is an active topic of current clinical investigations.

Michele R. Berman, MD, is a pediatrician-turned-medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children's Hospital. Her mission is both journalistic and educational: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.