TY - CHAP M1 - Book, Section TI - Laboratory Diagnosis of Infectious Diseases A1 - McAdam, Alexander J. A1 - Onderdonk, Andrew B. A2 - Jameson, J. Larry A2 - Fauci, Anthony S. A2 - Kasper, Dennis L. A2 - Hauser, Stephen L. A2 - Longo, Dan L. A2 - Loscalzo, Joseph PY - 2018 T2 - Harrison's Principles of Internal Medicine, 20e AB - The laboratory diagnosis of infection requires the demonstration—either direct or indirect—of viral, bacterial, fungal, or parasitic agents in tissues, fluids, or excreta of the host. Clinical microbiology laboratories are responsible for processing these specimens and also for determining the antibiotic susceptibility of bacterial and fungal pathogens. Traditionally, detection of pathogenic agents has relied largely on either the microscopic visualization of pathogens in clinical material or the growth of microorganisms in the laboratory. Identification has been—and often still is—based on phenotypic characteristics such as fermentation profiles for bacteria, cytopathic effects in tissue culture for viral agents, and microscopic morphology for fungi and parasites. These techniques are reliable but are often time-consuming. Increasingly, protein analysis or genotypic techniques are becoming standard methods for detection, quantitation, and/or identification of microorganisms in the clinical microbiology laboratory, replacing phenotypic characterization and microscopic visualization methods. This chapter discusses general concepts of diagnostic testing, with an emphasis on detection of bacteria. Detection of viral, fungal, and parasitic pathogens is discussed in greater detail in separate chapters (see Chaps. 185, 206, and 217, respectively). SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/18 UR - accesspharmacy.mhmedical.com/content.aspx?aid=1164035877 ER -