CLSI / BSAC Expert Rules

The BIOMIC V3 Resistance Monitoring Center™ contains over 2500 rules based on the human and animal CLSI documents, BSAC (UK), French, German and published recommendations. The Expert rules automatically check all tests for unlikely results, ESBL (screening & confirmatory), MRSA, inducible clindamycin resistance (D Test) and other resistance mechanisms. BIOMIC V3 verifies that all test results are adequately quality controlled. Predefined rules can be turned ON or OFF, and users may define their own rules to selectively report test results.

Annual software upgrades are available via CD or website download, including current published CLSI and BSAC guidelines and rules.

Examples of common resistance mechanism detected by BIOMIC V3:

1. D-Test Inducible clindamycin resistance. BIOMIC V3 instantly reads, interprets, and records D-Test results when erythromycin and clindamycin disks are placed and the appropriate organism conditions (macrolide-resistant isolates of S. aureus, coagulase-negative Staphylococcus spp., or beta-hemolytic streptococci) recommended by CLSI are met. When a flattening of the clindamycin zone is detected and displayed on-screen, these isolates will be reported as ‘clindamycin resistant.' (see CLSI M100) Learn more
2. ESBL Screening and confirmatory tests for ESBLs in Klebsiella pnuemoniae, K. oxytoca, E. Coli, and Proteus mirabilis. The standard ESBL screening test includes one or more disks (cefpodoxime, ceftazidime, aztreonam, cefotaxime, ceftriaxone) to detect presumptive ESBL production. A phenotypic confirmatory test utilizes ceftazidime and cefotaxime disks with and without clavulanate. A > 5mm increase in zone of the combo-disk versus the single confirms ESBL production. (see CLSI M100)
3. MRSA Penicillin-resistant, oxacillin-susceptible strains of Staph. aureus (coag positive). A 10-unit penicillin disk is preferred to test for penicillin-resistant, oxacillin-susceptible strains of Staph. aureus which produce B-lactamase. A penicillin disk should be used to test for the susceptibility of all B-lactamase-labile penicillins, ampicillin, amoxicillin, azlocillin, carbenicillin, mezlocillin, piperacillin, and ticarcillin. (see CLSI M100)
4. VRSA Vancomycin-resistant Staph. aureus. All Staphylococcal isolates with vancomycin disk zone diameters > 15 mm are considered susceptible, and those with zones < 14 mm should be tested by a reference MIC method to differentiate and confirm isolates with reduced susceptibility. (see CLSI M100)
5. Oxacillin-R coag-neg Staph The cefoxitin disk test is preferred for testing coagulase-negative staphylococci The cefoxitin disk has higher specificity and equal sensitivity to the oxacillin disk test to detect the gene encoding methicillin/oxacillin resistance. (see CLSI M100)
6. HLAR Screening test for high-level aminoglycoside resistant (HLAR) Enterococcus. High-level aminoglycoside resistance in Enterococcus species can be detected using gentamicin (120ug) and streptomycin (300ug) disks. Gentamicin and streptomycin zone < 6mm indicate HLAR. (see CLSI M100)
7. Strep. pneumoniae Screening test for Strep pneumoniae penicillin susceptibility Isolates of pneumococci with oxacillin disk zone sizes of > 20mm are considered susceptible to penicillin. Those with zones < 19mm should be tested by an MIC-method to accurately categorize. (see CLSI M100)

Epidemiology Reports and Charts

BIOMIC V3 complies with CLSI M39 guidelines in its extensive epidemiology-infection control reports program. There are numerous flexible report formats and users can customize and save commonly used reports.