New recommendations from the American College of Gastroenterology (ACG) on the management of colonic diverticulitis in the outpatient setting address an array of notable challenges in treating such patients, including discouraging the use of antibiotics and tricky dietary recommendations to prevent recurrence amid a lack of data.

“Many clinicians struggle to manage these patients, particularly those with recurrent disease, because they feel they have little to offer,” first author Anne F. Peery, MD, of the Division of Gastroenterology, University of North Carolina at Chapel Hill, Chapel Hill, NC, told Medscape Medical News. “That frustration can lead to unnecessary or even harmful treatments,” she said.

“We wrote the guideline to help gastroenterologists identify ways to support these patients.”

The guideline was published in the American Journal of Gastroenterology.

In the US, colonic diverticulitis, occurring in an estimated 3% of men and 5% of women, accounts for an approximately 1.7 million clinic visits annually, with related healthcare costs reaching an estimated $5.5 billion, the authors reported.

In most cases, about 88%, the disease presents as acute uncomplicated diverticulitis, representing inflammatory changes in and around the diverticulum. Those episodes typically present with the classic symptoms including lower abdominal pain, tenderness, fever, and sudden diarrhea or constipation.

Further features that support a diagnosis include older age, previous episodes, pain with movement, notably, a lack of vomiting, and elevated C-reactive protein, the authors explain.

In less common cases of complicated diverticulitis, inflammation occurs along with features that can include phlegmon, abscess, perforation, peritonitis, stricture, or fistula, they added.

Importantly, while most episodes of diverticulitis resolve within a few weeks, as many as a quarter of patients will go on to experience recurrences; after a second episode, at least a half will have a third episode, and patients with three or more episodes have a high risk for further recurrences, the authors said.

“This relapsing and unpredictable course can significantly impair quality of life and contribute to substantial symptom burden,” they noted.

Key recommendations in the guideline address some of the important decisions that need to be made to alleviate that burden.

Beginning with the consultation, the authors underscore that clinical evaluation alone is “inaccurate in most cases,” and they therefore recommend CT, especially at first presentation, to confirm a diagnosis and exclude alternative possibilities, as well as to accurately grade disease severity and guide treatment.

Colonoscopy?

While the overall risk for colon cancer with diverticulitis is low, those with complicated diverticulitis have several-fold higher rates than with uncomplicated cases, and therefore, “a follow-up colonoscopy is recommended after recovery from complicated diverticulitis.” The guideline states this as a strong recommendation with moderate certainty evidence.

In terms of uncomplicated diverticulitis, “colonoscopy should be considered after an episode among patients with alarm symptoms or in those who are not current with guideline-recommend colorectal cancer screening,” the guideline states as a conditional recommendation, with low certainty of evidence.

Antibiotics: Not When Risk Is Low

The guideline echoes recommendations of other guidelines regarding the use of antibiotics in suggesting that, with randomized trials showing little to no benefit, the drugs can be safely withheld in otherwise healthy and stable patients with uncomplicated diverticulitis.

Cases in which antibiotic use may indeed be appropriate include those who have high-risk features or develop complications such as comorbidities or who have concerning imaging findings, the authors noted in a conditional recommendation, with moderate certainty evidence.

“For decades, antibiotics were the standard of care for all patients with acute diverticulitis,” the guideline noted.

“Recent evidence has challenged the assumption that all patients with acute uncomplicated disease require antibiotics.”

The evidence includes a meta-analysis of four key randomized trials showing antibiotics to have little or no effect on reducing mortality risk, progression to complicated diverticulitis, or need for surgery, as well as little or no impact on readmission or recurrence in mild, left-sided acute uncomplicated diverticulitis.

“Based on these findings, we suggest selective rather than routine antibiotic use in patients with acute uncomplicated diverticulitis.”

Diet and Lifestyle

Robust evidence on dietary strategies to prevent recurrence of diverticulitis is lacking, with most studies evaluating diet in the context of incident diverticulitis, leaving practitioners with a clinical conundrum, Peery said.

“The most common question I get in clinic is, ‘What should I eat? What should I avoid?’” she said. “Patients need and want dietary guidance.”

Evidence confirms the benefits of healthy eating to potentially prevent a diverticulitis diagnosis — but prevention of recurrence is less clear.

“We now have enough evidence to advise patients recovering from diverticulitis to eat a healthy, balanced diet, with the understanding that diet in the years before diagnosis matters more than what they ate the night before,” Peery said.

The guideline’s specific recommendation of “a healthy diet, high in fruits, vegetables, whole grains and legumes and with limited consumption of red meat, processed grains, trans fats, and sweets,” to reduce the risk for recurrence comes with the caveat of a low certainty of evidence.

Nut Avoidance Not Necessary

Notably, while patients with diverticulitis have often avoided nuts, seeds, corn, and popcorn, the current evidence does not show an increased risk; therefore, avoidance is not recommended in the guideline.

“Although data on nut and seed consumption and recurrent diverticulitis are lacking, the effects are likely similar to those for incident disease,” the author noted.

“Based on available evidence, patients with a history of diverticulitis should not avoid consuming nuts, corn, seeds, or popcorn to prevent recurrence,” the authors wrote.

In addition, regular physical activity, achieving or maintaining a healthy weight, refraining from smoking and heavy alcohol use, all may also prevent recurrence, however, evidence supporting those measures is also described as being of low to very low certainty.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and Mesalamine

Avoidance of NSAIDs following an episode of diverticulitis is further recommended in the absence of a clinical indication, according to a conditional recommendation based on low certainty of evidence.

And in a strong recommendation, the guideline recommends against the use of mesalamine (5-aminosalicylic acid).

Despite having a “long and reassuring” safety record as an anti-inflammatory agent used in ulcerative colitis, the agent has shown no benefit in the treatment of patients with a history of diverticulitis in large international trials, the guideline notes.

Surgery

With elective surgery known to reduce, but not necessarily eliminate the risk for recurrence, the guideline recommends that in uncomplicated diverticulitis, elective surgery should be considered on a case-by-case basis, and primarily “for patients whose recurrent episodes significantly impair quality of life.”

Of note, the 5-year recurrence rate is approximately 60% without surgery compared with approximately 15% after elective colectomy.

Important risks, however, in the short-term include surgical site infections and/or anastomotic leak, while long-term risks associated with surgery include incisional hernia, permanent ostomy, anastomotic strictures, adhesive small bowel obstruction, and new-onset bowel dysfunction, the guideline noted.

Patients are commonly apprehensive about choosing surgery, and to address concerns, the guideline authors recommended that “shared decision-making that centers on patient-specific benefits and harms may help minimize decision regret.”

Furthermore, “validated decision aids and patient education tools are needed to help patients considering whether to have an elective surgery for diverticulitis.”

Stepped-Up Patient Education Needed

Such decision aids are further needed more broadly to better educate patients regarding the sometimes-complex issues of diverticulitis management, the authors underscored.

“Given the prevalence of misinformation, patients with diverticulitis benefit from targeted education.”

To assist with the dissemination of that, the guideline includes a patient education handout “to support informed, evidence-based care.”

Heterogeneity Is the ‘Biggest Challenge’

Commenting for Medscape Medical News, Jessica Cohan, MD, of the Department of Surgery, University of Utah and Huntsman Cancer Institute, Salt Lake City, Utah, said the guideline is importantly “rigorous and practical.”

“The biggest challenge [the clinicians face] from my perspective is that diverticulitis is such a heterogeneous disease,” she said. “An episode that might be safely managed at home in a young, healthy person may require a different approach in a frail or immunocompromised person.”

Meanwhile, “older adults may also present without the typical pain, fever, or leukocytosis, which can make it harder to determine who needs imaging or a higher level of care,” Cohan explained.

“The guideline acknowledges this heterogeneity. It provides guidance about when CT imaging is particularly useful and identifies higher-risk features that should influence decisions about antibiotics or more intensive evaluation.”

“It also asks clinicians to consider the patient’s comorbidities, overall health, and preferences when applying its recommendations.”

Treatment Not ‘One-Size-Fits-All’

In a previous study, Cohan and colleagues found that as many as 32% of patients with diverticulitis who had either elective surgery or observation reported having significant regrets regarding their decision.

Key factors associated with the regret included having worse gastrointestinal quality of life or issues with the decision-making process.

“Patients reported more regret when they felt less informed or supported, were less clear about their values, or had less involvement in the decision than they wanted,” Cohan said.

From a clinical perspective, the study showed “the importance of helping patients understand the tradeoffs, clarify treatment goals, and participate in the decision to the degree they want,” she noted. The guideline further underscores those principles, Cohan noted.

“The most important take-home message is that diverticulitis treatment should not be one-size-fits-all,” she said. “The right approach depends on the severity of the disease, the patient’s overall health, and how diverticulitis is affecting their life.”

“Clinicians need to identify patients at higher risk and tailor the intensity of evaluation and treatment accordingly [and] the guideline provides a practical framework for doing that.”

Peery had no disclosures to report. Cohan reported serving as the University of Utah Site Principal Investigator and as a member of the Clinical Advisory Board for the PCORI-funded COSMID trial.