MICROBIOLOGY

PRINCIPLES OF DIAGNOSTIC MEDICAL MICROBIOLOGY CONTD.... DIAGNOSIS OF INFECTION BY ANATOMIC SITE Wounds,  Tissues,  Bones,  Abscesses,  & Fluids: Microscopic study of smears and culture of specimens from wounds or abscesses often gives early and important indications of the nature of the infecting organism and thus helps in the choice of antimicrobial drugs.  Specimens from diagnostic tissue biopsies should be submitted for bacteriologic as well as histologic examination.  Such specimens for bacteriologic examination are kept away from fixatives and disinfectants, minced,  and cultured by a variety of methods. The pus in closed,  undrained soft tissue abscesses frequently contains only one organism as the infecting agent; most commonly staphylococci,  streptococci,  or enteric gram-negative rods.  The same is true in acute osteomyelitis,  where the organisms can often be cultured from blood before the infection has become chronic. Multiple microorganisms are frequently enco