ABSTRACT
The discovery of penicillin by Sir Alexander Fleming in 1928 marked the beginning of the modern era of antibiotics. 1 Following this discovery, the first penicillin resistance was reported in 1950. 2 Despite the availability of numerous antimicrobial agents available to treat microbial infections, sometimes these agents become ineffective against microorganisms such as bacteria, viruses, fungi, and protozoa. As a result infections persisted in the body increasing the risk of spread to others. Resistant microorganisms are emerging globally and are threatening our ability to fight common infections resulting in increased morbidity and mortality. Over time, changes occur naturally in the genetic composition of microbes due to overuse and misuse of antimicrobial agents which is one of the primary reasons for the emergence of antimicrobial resistance (AMR). Nearly two million Americans per year develop healthcare-associated infections (HAIs), resulting in 99,000 deaths. Most of the mortalities are due to antimicrobial-resistant pathogens. In 2006, two common HAIs, sepsis and pneumonia, were responsible for the deaths of nearly 50,000 Americans, costing the U.S. healthcare systems more than $8 billion. Estimates regarding the medical cost per patient with an antibiotic-resistant infection range from $18,588 to $29,069. The total economic burden placed on the U.S. economy is estimated to be as high as $20 billion in healthcare and $35 billion in lost 842productivity because of AMR. 2 AMR has emerged in Europe and North America as well due to inappropriate use of antibiotics in humans and animals. Resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), penicillin nonsusceptible Streptococcus pneumoniae (PNSSP), vancomycin-resistant enterococci (VRE), and extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae have emerged and spread into communities and hospitals. 3 In a recent study conducted at Children's hospital in China, it was found that there are five main pathogens responsible for multidrug-resistant infections. Extended spectrum β-lactamase (ESBL) was found in 1.9% cases making it the most common pathogen. 4 The second most common was MRSA, accounting for 1.51%. 4 The third, fourth, and fifth most common pathogens were Carbapenem-resistant Enterobacteriaceae (CRE) in 0.17% of the cases, Carbapenem-resistant Acinetobacter baumannii (CRAB) in 0.10% of the cases, and multidrug-resistant/pandrug-resistant Pseudomonas aeruginosa (MDR/PDR-PA) in 0.03% of the cases, respectively. 4
