Just enough, but not too much, antibiotics for CAP patients

Prudent approaches to treating community-acquired pneumonia in the hospital include achievable goals, such as using the lowest number and spectrum of antibiotics and shortening treatment durations.

Rational use of antibiotics in the hospital is imperative, especially in an era of such deadly consequences as antibiotic resistance and Clostridium difficile, said Scott A. Flanders, MD, FACP, during a Friday-morning session on pneumonia.

In 2016, a CDC analysis of more than 300 hospitals showed that 55% of patients hospitalized between 2006 and 2012 received antibiotics. Although use remained stable during that time period, there was a significant shift toward broad-spectrum drugs versus narrow-spectrum drugs.

Many hospitalized patients need broad-spectrum antibiotics, but several studies have estimated that anywhere from 30% to 50% of antimicrobial use in U.S. hospitals is inappropriate, noted Dr. Flanders, a professor of medicine and director of the hospital medicine program at the University of Michigan Medical School in Ann Arbor.

“That's a lot of ground to make up,” he said. “When you look at the conditions where we're seeing antibiotic use in U.S. hospitals, pneumonia, urinary tract infections (UTIs), and skin and soft-tissue infections are the big three, and pneumonia is the big daddy of them all,” with more than half of use dedicated to pneumonia and UTIs.

During his talk, Dr. Flanders offered prudent approaches to treating community-acquired pneumonia (CAP) in the hospital. He suggested using the lowest number and spectrum of antibiotics and shortening treatment durations if at all possible.

Some patients will benefit from atypical coverage with a macrolide, he noted. For sicker hospitalized patients, especially the ICU population, Dr. Flanders recommends use of a beta-lactam plus a macrolide versus a beta-lactam alone. “A lot of my patients in my hospital don't look so good, so I slant toward the beta-lactam plus the macrolide,” he said.

That said, an increasingly large number of ward patients—especially those in whom Legionella has been considered and is not suspected—may be candidates for beta-lactam monotherapy, Dr. Flanders said. “This may be the patient who gets hospitalized because their COPD is flaring; it's not their pneumonia, per se, or they have heart failure on top of it,” he said.

When deciding between fluoroquinolones versus a beta-lactam and a macrolide, Dr. Flanders again suggested keeping the patient's condition in mind. “Many hospitalists debate between those. I would say the outcomes are comparable for ward patients. I think beta-lactam plus macrolide seems to be better for the sicker patient populations, but beware of the fluoroquinolones,” he said, noting important downsides such as adverse drug events and declining activity of the broad-spectrum drugs against Pseudomonas and Escherichia coli.

Dr. Flanders said physicians at his institution are moving away from fluoroquinolones, instead preferring beta-lactams/beta-lactamase inhibitors, with azithromycin as their empiric treatment choice.

Some institutions, he said, are choosing to use beta-lactams plus doxycycline, which has some activity against C. difficile. “That may actually be a very reasonable regimen if C. diff in particular is a problem at your institution,” he said. “There will be less outcome data for you to hang your hat on, especially with the doxy-based regimens, but a lot of experienced institutions out there have had good results.”

There are varying thoughts on CAP treatment durations, as well. The 2007 guidelines from the American Thoracic Society and Infectious Diseases Society of America recommend a minimum of five days and that the patient should be afebrile for 48 to 72 hours and have no more than one CAP-associated sign of clinical instability (e.g., heart rate greater than 100 beats per minute). “That was great advice, but it had actually never been studied until this last year, where we got a randomized trial comparing that very approach compared to what the docs usually do,” Dr. Flanders said.

The trial, published in the September 2016 JAMA Internal Medicine, found that five days of treatment versus the doctors' preference (a median of 10 days) produced similar 30-day success rates, and there were fewer 30-day readmissions in the five-day treatment group. In addition, 70% of the intervention group was stable enough to receive five days of treatment, Dr. Flanders noted. “This study suggested it might actually be a better approach than longer durations,” he said.

However, when it comes to stopping therapy, “we don't do this very well,” said Dr. Flanders. Data from his team's ongoing study across 10 Michigan hospitals and 2,500 pneumonia patients showed that about 53% of patients received excess duration of antibiotic treatment. “There's a huge opportunity for us to shorten treatment durations, and I think we need to move more in that direction.”