Microbiology – We offer in house gram staining to identify bacteria in synovial fluid, wound exudates, respiratory excretions or other body fluids. Samples are submitted overnight to an outside reference laboratory for culture and antibiotic sensitivity testing. In the figure below left colonies of bacteria are growing on a blood agar plate. In the figure below right 4 out of 5 disks containing different antimicrobial medications demonstrate "zones of inhibition" around them. This indicates that the bacteria growing on this plate are sensitive to those antibiotics.