Introduction and History of Staphylococcus aureus Infection
Introduction
Community-acquired methicillin-resistant Staphylococcus aureus, commonly known as CA-MRSA, is a prevalent and potentially life-threatening infection that can occur in both the adult and pediatric population. During the past 2 decades, clinicians have performed research to try to better understand the biology of this pathogen and to develop pharmacologic treatments that can combat this infection effectively. The objectives of this review are to discuss the history of CA-MRSA infection, along with its epidemiology, risk factors, and resistance profiles, and to identify the various medications available to treat this infection.
History of Staphylococcus aureus Infection
Staphylococcus aureus is a gram-positive cocci pathogen. In the early 1940s, the major treatment available to combat this organism was penicillin, and all isolates were sensitive to penicillin during that period. With this antibiotic, the mortality rate of bacteremia caused by S. aureus decreased from a striking 80% to 25% (Ladhani & Garbash, 2005). In 1944, the first penicillin-resistant strain of S. aureus was discovered. As clinicians used more and more penicillins as the primary treatment for S. aureus infection, the prevalence of penicillin-resistant strains increased in the 1960s. It was during this time that a new class of antibiotics was developed to target this pathogen specifically. This class of antibiotics is known as the penicillinase-resistant penicillins, which includes nafcillin, dicloxacillin, and oxacillin. One year after this class of antibiotic was developed, a resistant strain known as methicillin-resistant S. aureus (MRSA) was discovered in both the United States and the United Kingdom (Zaoutis et al., 2006). MRSA became increasingly prevalent, especially in larger hospitals, in the 1970s. From the late 1970s to the early 1990s, MRSA was usually a hospital-acquired pathogen. It was not until 1998 that the first case of CA-MRSA in children was identified (Ladhani & Garbash; Zaoutis et al.). Since then, CA-MRSA has become more prevalent in children throughout the United States ( Table 1 ).