Бак посев экссудат наружного уха (правое) на респираторные инфекции (A.R.I. WELL D‐ONE)

Aerobic and facultative anaerobic culture (routine bacterial culture) is used to identify the causative organism in suspected infections across a range of specimen types. By isolating and characterizing the agent, the test guides targeted antimicrobial therapy, including selection of antibiotics or bacteriophages. Follow-up cultures may also be used to assess the microbiologic response and gauge the effectiveness of treatment. This culture-based approach supports organism-level diagnosis when direct microscopy or syndromic testing is inconclusive, and provides quantitative growth information that helps distinguish colonization from infection in an appropriate clinical context.

The human microbiota consists of microorganisms that inhabit the skin and mucosal surfaces. The greatest proportion resides in the gastrointestinal tract (approximately 40%), with the remainder distributed across the skin, oropharynx, genitourinary tract, and other sites. By composition, the microbiota is often described as resident (up to 90% of organisms present), facultative (less than 10%), and transient (no more than 0.5%). Microorganisms are also categorized by pathogenic potential: nonpathogenic species that do not cause disease; opportunistic organisms that are typically present in small numbers but may proliferate under favorable conditions and produce inflammation; and pathogenic organisms that are not components of normal flora and are established causes of infectious disease. Bacteriological culture—an aerobic and facultative anaerobic culture—determines the qualitative and quantitative composition of microorganisms in a clinical specimen and enables detection of pathogens. When opportunistic organisms are recovered in high titer or true pathogens are isolated, antimicrobial susceptibility testing is performed to inform therapy, including testing against antibiotics and bacteriophages.