Product Center

These discs are used for semi-quantitative in vitro susceptibility testing by the agar disc diffusion test procedure of common, rapidly growing and certain fastidious bacterial pathogens. These include the Enterobacteriaceae, Staphylococcus spp., Pseudomonas spp., Acinetobacter spp., Enterococcus spp., Vibrio cholerae and, by modified procedures, Haemophilus influenzae, Neisseria gonorrhoeae, Streptococcus pneumoniae and other streptococci. NOTE: Special procedures are required for testing pneumococci, enterococci and methicillin/oxacillin-resistant staphylococci, for performing β-lactamase tests and for screening and confirmatory tests for ESBLs; see the "RESULTS" section.

Agar diffusion methods employing dried filter paper discs impregnated with specific concentrations of antimicrobial agents were developed in the 1940s. In order to eliminate or minimize variability in this testing, Bauer et al. developed a standardized procedure in which Mueller Hinton Agar was selected as the test medium.^1,2

Various regulatory agencies and standards-writing organizations subsequently published standardized reference procedures based on the Bauer-Kirby method. Among the earliest and most widely accepted of these standardized procedures were those published by the U.S. Food and Drug Administration (FDA)³ and the World Health Organization (WHO).^4,5 The procedure was adopted as a consensus standard by the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS) and is periodically updated.^6,7 The latest CLSI documents should be consulted for current recommendations.

Sensi-Disc™ brand discs are 6-mm discs prepared by impregnating high quality absorbent paper with accurately determined amounts of antibiotic or other chemotherapeutic agents. Discs are clearly marked on both sides with letters and numbers designating the agent and the drug content. (See chart giving concentrations of reactive ingredients.) The drug content of discs is assayed by the methods established by the FDA or by methods similar or comparable to those published in the United States Federal Register.

Sensi-Disc agents are furnished in cartridges containing 50 discs each. The last disc in each cartridge is marked "X" and contains the drug as coded. Cartridges are for use in BBL™ Sensi-Disc™ Dispensers; these include a Single Disc Dispenser, an 8-Place Dispenser for 100 mm-style Petri dishes, 6- and 8-Place Self-Tamping Dispensers for 100 mm-style dishes and a Self-Tamping 12-Place Dispenser for 150 mm-style plates.

For in vitro Diagnostic Use.

Follow directions for use; disc performance depends not only on disc potency, but on use of proper inoculum and control cultures, functional pretested plates, proper storage temperature and other factors.

Observe aseptic techniques and established precautions against microbiological hazards throughout all procedures. Sterilize cultures, containers and other contaminated materials after use.