Quinupristin/dalfopristin

Gram-positive pathogens are associated with both community- and hospital-acquired infections. These infections may be life-threatening in hospitalised patients, especially in those with significant underlying acute or chronic diseases. Prompt and appropriate antimicrobial therapy is essential for avoiding morbidity and mortality. The concept of appropriate therapy is being redefined by increasing antimicrobial resistance, especially amongst Gram-positive pathogens. This has been most dramatic with penicillin-resistant Streptococcus pneumoniae in the community, including cross-resistance to other classes of antimicrobial agents. In the US, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) with community isolates is significant. For hospital-acquired Gram-positive pathogens, MRSA, vancomycin-resistant Enterococcus species and vancomycin-intermediate resistant and -resistant S. aureus are a great concern, particularly as the frequency of recovery of these pathogens from infected patients increases. The net result of these various resistance issues is a reduction in the number of appropriate antimicrobial agents for treating infected patients. Quinupristin/dalfopristin is a parental streptogramin with a spectrum of activity that includes Gram-positive pathogens, including those resistant to other classes of antimicrobial compounds. In this review, data summarising the frequency of recovered Gram-positive pathogens from various infectious diseases, the escalating prevalence of resistance amongst Gram-positive pathogens and the factors making quinupristin/dalfopristin a suitable agent for treating patients infected with Gram-positive organisms will be discussed.