Big Bugs, Few Drugs: the Challenge of Infectious Disease and Antimicrobial Stewardship
Image: Belinda Ostrowsky, MD, MPH (Infectious Diseases)
Image: Yi Guo, Pharm.D. (Moses)
Image: Philip Chung, Pharm.D. (Weiler)
Treating a patient with an infectious disease often turns a physician into a detective. Starting an appropriate treatment therapy as quickly as possible can significantly reduce the patient’s mortality risk (which by a recent published study by Lodise et. al. from Albany Medical Center may rise from 19% to 44% over the first 53 hours if untreated) and the chance of spreading that infection to others. In this race against the clock, an empiric therapy regimen—often, administering an intravenous broad-spectrum antibiotic to wipe out a number of potential offenders—can be a prudent approach.
When more laboratory results become available, treatment can be changed to a more specific antibiotic to target the microorganism causing the infection. But for a first-year resident or even an experienced attending physician treating a high volume of newly transferred patients, the option to streamline or de-escalate an antimicrobial may be overlooked, or a more cautious approach chosen for a patient who seems to be improving.
Longer-than-needed durations, medical regimens with redundant coverage, delayed regimens, suboptimal dosing and use of drugs that don’t target the causal pathogen are examples of inappropriate antimicrobial therapy, which has been linked to issues such as higher antibiotic resistance rate, longer duration of hospitalization, increased costs, and adverse events ranging from mild skin eruptions to increased mortality. Recent studies have suggested that a significant percentage of antibiotics prescribed in healthcare settings are inappropriate.
Some U.S. medical centers have responded with dedicated antimicrobial “stewardship” efforts. In July 2008, Montefiore Medical Center initiated a multifaceted interdisciplinary program to educate, support, and advise practicing physicians throughout its extensive Bronx network of hospitals, ambulatory care clinics, and nursing homes. Spearheaded by infectious diseases specialist Belinda Ostrowsky, MD, MPH (Infectious Diseases) and infectious diseases specialty pharmacists Yi Guo, Pharm.D. (Moses) and Philip Chung, Pharm.D. (Weiler), the program seeks to foster judicious antimicrobial use toward better patient care and safety; improved clinical outcomes; reduced resistance; and fewer healthcare-acquired infections such as C. difficile colitis, a potentially fatal complication that can develop from the use of commonly prescribed antibiotics.
The emergence and spread of resistance—a self-preserving genetic mutation that renders a pathogen unresponsive to treatment—is particularly pressing given the stagnation of new antimicrobials on the market. Reduced pharmaceutical sponsorship, increased regulatory requirements, and an overall failure to deliver novel antibiotic agents have created low return on investment for antibiotic development, an issue identified by the Infectious Diseases Society of America (IDSA) as “a frightening twist in the antibiotic resistance problem that has not received adequate attention from federal policymakers.”
A “less is more” approach is fundamental, according to Ostrowsky, who specialized in infections and public health at a Harvard-affiliated teaching hospital and whose medical background includes assignments to the Center for Disease Control and Prevention’s Epidemic Intelligence Service and the Westchester County Department of Health. “Overusing these important drugs can breed serious problems, so we need to save what we have,” she said.
Ostrowsky and her team are currently focusing on Montefiore’s inpatient units to formulate a system-wide approach to consistent treatment protocols, a plan based on IDSA guidelines, aggregate data on antimicrobial resistance and microbiology at Montefiore, and exemplary clinical methods practiced by departments throughout the system. Requiring providers to justify use of broad-spectrum antibiotics, optimizing dosages and transitioning administration methods (primarily intravenous to oral), and identifying opportunities to routinely de-escalate and streamline treatment regimens are key components of her stewardship plan.
Despite the serious implications of widespread disease, growing resistance, and no new treatment options, less than half of the country’s hospitals currently have formal antimicrobial stewardship programs. Inadequate resources and/or administrative support may be part of the reason. Yet even in the best circumstances, guidelines for establishing antimicrobial stewardship are nascent—IDSA recommendations, for example, were only established in 2007.
“There’s no blueprint to show us how to run this kind of program, so our real work right now is to identify the systems that are already in place and design a program that truly meets our patients’ needs,” Ostrowsky said. Such an endeavor is made more complex by Montefiore’s sheer volume (nearly 1500 beds and over 75,000 annual admissions among numerous geographically scattered inner-city facilities); its teeming emergency department, where many antibiotics courses are initiated; and the broad diversity of its providers. However, Ostrowsky’s team of seasoned infectious diseases specialty pharmacists in both the Moses and Weiler divisions, as well as liaisons built with the administration, infection control, the pharmacy and therapeutics committee, and microbiology, have made for a strong beginning.
Stewardship programs throughout the country have shown to be cost effective, demonstrating a 22-36% decrease in antimicrobial use and, in some cases, saving as much as $900,000 (antimicrobials account for up to 30% of U.S. hospital pharmacy budgets). By encouraging physicians to be cautiously “frugal” in prescribing antimicrobials, conjoined effort between departments of infectious disease and pharmacy may prove financially beneficial. Ostrowsky’s first concern, however, is patient safety. “We want to make sure that we are providing the best possible clinical care,” she said. “Saving money for Montefiore would be a side benefit, especially if it comes from well-matched dosing that preserves the effectiveness of the drugs we have available.”