The primary source of information about most bacterial infec-tions is the microbiology report. The microbiology report should be viewed as a tool to be used along with clinical indicators to de-termine whether a patient is colonized, infected, or diseased.
When specimens are sent to the laboratory for culture, results usually show three components: the smear and stain, the culture and organism identification, and the antimicrobial susceptibility (ie, sensitivity). As a marker for the likelihood of infection, the smear and stain generally provides the most helpful information because it describes the mix of cells present at the site at the time of specimen collection. Culture and sensitivity processes specify which organisms are recognized and which antibiotics inhibit growth.