Treatment strategies and recommendations for Pseudomonas aeruginosa infections.

1. Nicholas M. Moore, MS, MLS(ASCP)[⇑][1] 1. Rush University, Department of Medical Laboratory Science, Chicago, IL 2. Maribeth L. Flaws, PhD, SM(ASCP)SI 1. Rush University, Department of Medical Laboratory Science, Chicago, IL 1. Address for Correspondence: Nicholas M. Moore, MS, MLS (ASCP), Department of Medical Laboratory Science, 600 S. Paulina St., Suite 1014, Chicago, IL 60612, 312-942-2111, Fax: (312) 942-6464, Nicholas_Moore{at}rush.edu 1. Describe the mechanism of action of the primary anti-pseudomonal agents. 2. List the advantages and disadvantages of combination drug therapy. 3. List the advantages and disadvantages of mono drug therapy. 4. Determine which antibiotic combinations are appropriate for treatment of various infections caused by Pseudomonas aeruginosa . Pseudomonas aeruginosa is a common cause of infection, especially hospital-acquired infections. It is opportunistic, more often causing infection in immunocom-promised hosts and it is often antibiotic resistant, complicating the efficacy of therapy. These factors have increased the number of patients infected with P. aeruginosa , increased the severity of those infections, and caused a great deal of conflict amongst infectious disease practitioners on how to appropriately and effectively manage their treatment. The following sections will describe appropriate treatment regimens for non-cystic fibrosis patients with infections caused by P. aeruginosa and discuss empiric as well as mono versus combination therapy protocols. Anti-Pseudomonas Antibiotics The antimicrobial agents listed in Table 1 have activity against P. aeruginosa . Beta Lactams Beta-lactams are a broad group of antibiotics that include penicillins, cephalosporins, monobactams and carbapenems. At the molecular level, the beta-lactams have thiazolidine and beta-lactam rings to which is attached a side chain. Beta-lactams are one of the most widely prescribed antibiotic agents in the United States. They are bactericidal and act by binding to transpeptidases [also known as penicillin-binding proteins (PBP)] thereby interfering with the synthesis of the peptidoglycan layer of the cell wall. Bacteria, including P. aeruginosa , become resistant to beta-lactams by either possessing enzymes (beta-lactamases) that hydrolyze the beta-lactam ring or altering the PBPs such that the antimicrobial agent can no longer bind and exert its effect. The beta-lactams that have the most activity against P. aeruginosa include piperacillin, ticarcillin, 3rd and 4th generation cephalosporins (ceftazidime and cefepime respectfully), and carbapenems like imipenem… ABBREVIATIONS: DNA = Deoxyribonucleic Acid, IDSA = Infectious Disease Society of America, ATS = American Thoracic Society. 1. Describe the mechanism of action of the primary anti-pseudomonal agents. 2. List the advantages and disadvantages of combination drug therapy. 3. List the advantages and disadvantages of mono drug therapy. 4. Determine which antibiotic combinations are appropriate for treatment of various infections caused by Pseudomonas aeruginosa . [1]: #corresp-1