"Bad Bugs" Causing Respiratory Infections are Increasingly Resistant to Antibiotics

Between 1995 and 2003, the major bad bugs causing respiratory infections in hospitals have grown increasingly resistant to commonly prescribed antibiotics, according to data from the Antimicrobial Resistance Management (ARM) Program. The sharpest decline was between 1995 and 1998. One exception: Streptococcus pneumoniae, which actually became less resistant to the antibiotics cefuroxime (a second-generation cephalosporin) and ceftriaxone (a third-generation cephalosporin).

Approximately 2 million people acquire bacterial infections in US hospitals each year and 90,000 die. Approximately 70 percent of those infections are resistant to at least one drug.

The magnitude of antimicrobial resistance has reached epic proportions, said John G. Gums, PharmD, ARM program director, during the 70th annual international scientific assembly of the American College of Chest Physicians. Once a phenomenon restricted to developing countries or Asia, the impact of resistance to antibiotics is now being felt by every hospital and community practice in the United States.

The national decline in susceptibility of the primary pathogens causing respiratory tract infections in hospitalsStreptococcus pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae, and Pseudomonas aeruginosato antibiotics now in use underscores the necessity for hospitals and institutions to benchmark resistance at the local level to limit the effect of antibiotic resistance on patients and the public, added Gums, professor of pharmacy and medicine in the Departments of Pharmacy Practice and Community Health and Family Medicine at the University of Florida, Gainesville.

The analysis included several classes of antibiotics, from the penicillins to newer agents such as the fourth-generation cephalosporins and fluoroquinolones.

Antibiotic resistance has been identified as an impending public health crisis, he said. For example, 15 years ago, there were no appreciable levels of vancomycin-resistant enterococci (VRE); seven years ago, vancomycin-intermediate Staphylococcus aureus (VISA) did not exist; and two years ago, we only hoped that vancomycin-resistant staphylococcus aureus (VRSA) would never materialize.

There was a time when one could consider treating upper respiratory infections in children with 40mg/kg/day of amoxicillin, Gums continued. Well, VISA, VRSA, and penicillin-resistant Streptococcus pneumoniae (PRSP) are here and continue to spread. While there are many factors that have been identified as triggers for increasing resistance, one factor most experts believe contributes is the increased use of inappropriate antibiotics. The ARM Program was developed to assist institutions and outpatient centers in identifying the scope of the resistance problem unique to their patient population or geographic location. Local recognition of resistance trends is mandatory to determine the appropriate strategies that will eventually reduce the pressures for resistance.

The ARM Program database has served as one of the epidemiological databases for the new Antibiotic Selection for Community-Acquired Pneumonia (CAP) Guidelines for Management of CAP. Recently, the ARM Program has also begun to correlate antibiotic utilization rates to resistance trends in an effort to give institutions the ability to screen for causal relationships between use and resistance. Through benchmarking at a variety of levels, the ARM Program can work with individual institutions or systems to assist them as they tackle the problem of resistance to antimicrobials.

The ARM program has been in existence since 1997 and has worked with more than 345 institutions throughout the United States and Puerto Rico and, as of Oct. 18, 2004, 26.9 million isolates have been collected in the ARM database. Analysis of data from the ARM Program has been presented at national and international meetings and has produced more than 13 national abstracts and, numerous peer-reviewed publications.

Source: D.A. Hughes & Associates