Antimicrobial resistance: Current status and future direction

Background: Antimicrobial resistance is initiated through mutations in bacterial genes, culminating in end products that help circumvent the action of specific antimicrobial agents. Resistant mutants can proliferate under a number of circumstances but primarily through the action of selective pressure from the overuse of antimicrobial agents. Methods: The results of surveillance studies over approximately the last ten years were evaluated. Conclusion: Resistance rates in the group of microorganisms associated with respiratory tract infections had been increasing rapidly over the past 10 years, but, recently, many seem to have reached a plateau. However, newer, more invasive clones of methicillin resistant Staphylococcus aureus (MRSA), differing from health care-associated MRSA (HA-MRSA), and typically associated with community-acquisition (CA-MRSA), recently have begun to proliferate. Burgeoning use of fluoroquinolones has impacted the Gram-negative bacilli (e.g., Pseudomonas aeruginosa, Escherichia coli, and Salmonella), causing their resistance rates to approach the critical point. A better understanding of the epidemiology of resistance and responsible use of antimicrobial agents are mandatory if the continuing rates of increasing resistance are to be abrogated.