Antibiotics Can Help Some Patients Avoid Appendectomies, Study Finds

Woman with abdominal pain.

 Phynart Studio / Getty Images

Key Takeaways

  • A new study found some people can skip an appendectomy and treat appendicitis effectively with antibiotics.
  • Doctors find that some patients are still better off getting surgery.
  • Incorporating antibiotics into treatment for appendicitis will give doctors and patients another option to consider.

Some patients may resolve appendicitis with a course of antibiotics instead of undergoing surgery for an appendectomy, according to new research.

That said, surgery is sometimes the best course of action for some patients.

The study, published on October 5 in The New England Journal of Medicine, detailed a trial conducted by the Outcomes of Drugs and Appendectomy (CODA) Collaborative. The trial included 1,552 patients with appendicitis in hospitals across 14 states. Half of the participants took antibiotics, the other half underwent appendectomies.

Both groups felt well at 30 days, David Talan, MD, co-principal investigator and professor of emergency medicine and medicine/infectious diseases at the David Geffen School of Medicine at UCLA in California, said in a statement.

Half of the patients who took antibiotics were discharged from the emergency department and were not hospitalized. About 3 in 10 patients in the antibiotic group still had to undergo surgery within 90 days. Those who didn’t undergo surgery received a 10-day course of antibiotics administered intravenously for the first 24 hours. They took antibiotic pills for the remaining days.

“In terms of overall health status, antibiotics were no worse than surgery and allowed most people to avoid an operation in the short term,” Talan said.

How Antibiotics Work

Appendicitis is an infection marked by bacteria and inflammation in the appendix, David R. Flum, MD, co-principal investigator of the study and professor and associate chair of surgery at the University of Washington School of Medicine, tells Verywell.

Flum thinks the antibiotics work because they reduce the bacterial load. That way the body can focus on lowering the inflammation.

Antibiotics as Appendicitis Treatment

For decades, having an appendectomy has been the standard of care. But doctors have also used antibiotics in the past. This was especially true during wars when surgery wasn’t an option.

Studies in the 1990s didn’t provide solid evidence due to bias in randomizing patients. Some trials only included patients with low-grade appendicitis, and not those with acute appendicitis—or patients in immediate pain.

“Nobody really believed the results of those trials,” Flum says. In this recent study, however, researchers randomized patients.

“We included everybody who typically gets an appendectomy,” he says. “Overall, what we found is that the vast majority could avoid an operation, at least by three months."

The CODA researchers only followed patients for 90 days, but other research has followed people as long as five years.

“It appears that the majority of antibiotic-treated patients will not ultimately require an appendectomy,” Talen says. “Recurrence, if is it going to happen, seems to mostly occur in the first two years after the initial attack and recovery with antibiotics."

The team plans to follow the patients for a longer amount of time to better understand longer-term outcomes. “If appendicitis recurs, some studies have reported success with antibiotic treatment,” he says.

Antibiotics Versus Appendectomy

There were advantages and disadvantages to each treatment. For instance, patients who had an appendicolith (a calcified deposit in the appendix) tended to have a higher risk of needing surgery. About 25% of patients with acute appendicitis have this stone-like deposit.

Those with appendicolith had a 4-in-10 chance of needing an appendectomy by 90 days. Complications for taking antibiotics weren’t significant, but seemed to be more common in those who had an appendicolith.

Doctors can discern which patients are better off having surgery as the first line of treatment. Because doctors can identify the deposit on imaging, they can inform patients about their appendicolith and factor this into shared decision-making. But knowing that patients may have time to put off an appendectomy may be useful for those who do not have insurance at the time, are out of town, or don’t want to be in hospitals as a result of the pandemic, Flum says.

“People treated with antibiotics more often returned to the emergency department, but missed less time from work and school,” Bonnie Bizzell, chair of the CODA patient advisory board, added in a statement. “Information like this can be important for individuals as they consider the best treatment option for their unique circumstance. The CODA trial is really the first of its kind to capture these measures for shared decision-making about appendicitis.” 

The chance of missing a type of cancer in the appendix is a risk from foregoing an appendectomy. But that form of cancer is rare, Giana H. Davidson, MD, a study investigator and an associate professor of surgery at University of Washington School of Medicine, tells Verywell.

What This Means For You

If you have appendicitis, talk to your doctor to see if you are a good fit for antibiotic treatment. If you try them and they don't work, you may have to undergo an appendectomy.

Benefits of Keeping Your Appendix

Who cares if you get rid of your appendix? Many believe you don't need it anyway. But that may not be a reason to rush under the knife.

Recent studies in evolutionary biology reveal the benefits of having and retaining an appendix, Heather F. Smith, PhD, an anatomy professor at Midwestern University in Illinois, tells Verywell.

“The appendix functions as a safe house for beneficial gut bacteria," she says. "During times of gastrointestinal distress, diarrhea often transports good gut bacteria out of the GI tract. However, the appendix is a blind pouch, and therefore acts as a reservoir maintaining good gut bacteria, which can then repopulate the gut."

It also has a high concentration of lymphoid tissue, which supports the immune system and helps mount the body’s defense against invading pathogens, Smith adds.

Another recent study found that people who have had their appendix removed suffer higher rates of infection of Clostridium difficile (or C. diff) compared to those who still have the organ.

C. diff is the most common microbial cause of healthcare-associated infections in the U.S. In 2015, it caused half a million infections among patients in the United States, according to the U.S. Centers for Disease Control and Prevention (CDC).

“If an appendix does not need to be removed, it would often be to a person’s benefit to retain it," Smith says. "In other words, the primary downside of an appendectomy is the loss of these helpful properties of an appendix. Therefore, the prospect of treating appendicitis with non-surgical options is promising."

Predicting Appendicitis Outcomes

Flum believes the study will give doctors and patients another option to consider for certain patients.

If Flum sees a patient who has a high risk for complications, he’s likely to recommend surgery. But he said he will present both sides to the patient in order to let them know about the advantages and disadvantages of trying antibiotics.

In the future, he hopes to see a predictive calculator that can take into account a patient's age, health status, white blood cell count, and imaging data, among other information. This could potentially improve predictions about a patient’s outcome.

“I think it’s going to create a lot more conversations,” he says. “Antibiotic treatment will be good for many people but not for all."

That said, people have to take appendicitis seriously. He doesn’t want to see it go untreated. Still, knowing that you may not need surgery—or that you may not even have to be hospitalized—could be a “game-changer” for a lot of people, Flum says.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Flum, D, et al. A randomized trial comparing antibiotics with appendectomy for appendicitis. NEJM. Oct. 5, 2020. doi:10.1056/NEJMoa2014320

  2. Smith H, et al. Morphological evolution of the mammalian cecum and cecal appendix. Comptes Rendus Palevol. 2017;16(1):39-57. doi:10.1016/j.crpv.2016.06.001

  3. Centers for Disease Control and Prevention. Nearly half a million Americans suffered from Clostridium difficile infections in a single year. March 22, 2017.

By Kristen Fischer
Kristen Fischer is a journalist who has covered health news for more than a decade. Her work has appeared in outlets like Healthline, Prevention, and HealthDay.