RT Book, Section A1 Parker, Sarah K. A1 Child, Jason A1 MacBrayne, Christine E. A1 Haynes, Andrew A1 Searns, Justin A2 Hay Jr., William W. A2 Levin, Myron J. A2 Abzug, Mark J. A2 Bunik, Maya SR Print(0) ID 1172112949 T1 Antimicrobial Therapy T2 Current Diagnosis & Treatment: Pediatrics, 25e YR 2020 FD 2020 PB McGraw-Hill Education PP New York, NY SN 9781260457827 LK accesspediatrics.mhmedical.com/content.aspx?aid=1172112949 RD 2024/10/09 AB The discovery and rapid development of targeted antimicrobial agents, beginning in the 1930s, are among the most important scientific developments of 20th-century medicine. These drugs have forever changed the practice of medicine, and antimicrobials remain one of medicine’s most effective and widely used interventions. However, despite the impact of these drugs, choosing an appropriate antimicrobial can be a complex and difficult task. Optimal antimicrobial use requires appreciation of the complicated interactions between host, organism, and drug. This decision-making process, summarized in Table 39–1, begins with an accurate working diagnosis, based on the patient’s history, physical examination, exposure history, and initial laboratory tests. From this foundation, the clinician must consider the most likely organism(s) and that organism’s likely pattern of antimicrobial susceptibility. This information is considered in the context of numerous patient-specific factors, including age, immune status, relevant comorbidities, site of infection, and microbiology of his or her prior infections. Empiric therapy should be changed to definitive therapy as the clinical course evolves and additional laboratory data are available. Obtaining appropriate microbiologic specimens helps facilitate this transition.