Exam 11: Laboratory Methods and Strategies for Antimicrobial Susceptibility Testing

Standardization of antimicrobial susceptibility testing optimizes bacterial growth so inhibition of growth can be attributed to the antimicrobial agents tested and results are accurate,reproducible,and consistent regardless of the microbiology laboratory performing the test.Which of the following incubation conditions are used for common (i.e. ,nonfastidious)bacterial isolates using manual techniques?

As a result of the organism going through several doubling generations of growth before inhibition,a haze of bacterial growth occurs on the agar around the disk.This phenomenon,which should be ignored,can be observed when testing which class of antibiotics?

A newly defined interpretive category termed "Susceptible-Dose Dependent" (SDD)implies susceptibility of an isolate is dependent on dosing regimen.Which of the following statements is correct?

Bactericidal tests should be performed:

The serum bactericidal test (SBT)involves:

For clinical decision-making carbapenemase production should be detected using:

The primary goal of antimicrobial susceptibility testing is to:

Staphylococcus aureus was isolated from a patient's surgical wound.In a disk diffusion assay,the isolate was found to be resistant to cefoxitin (30 µg disk).With which antibiotic should this patient's infection be treated?

Quality control results for disk diffusion AST using appropriate ATCC strains of bacteria showed zone size diameters decreasing over time for a few antimicrobials.Which of the following statements is a possible explanation?

Data review process for AST profiles:

Antimicrobial susceptibility testing should be performed when:

A staphylococcal isolate that gives a negative result using the Cefinase disk and tests resistant to penicillin by disk diffusion means that:

A D-test is set up on a S.aureus isolate.There was no zone around the Erythromycin disk and the zone of inhibition around the clindamycin disk adjacent to the erythromycin disk was interpreted as susceptible.Thus,the resistance mechanism for the erythromycin is due to:

Up-to-date tables that list potential antimicrobial agents to include in batteries for testing against particular organisms or organism groups are published by the:

Advantages of automated susceptibility tests (e.g. ,Vitek 2 and Microscan Walkaway)include but are not limited to:

An important requirement for appropriate inoculum preparation in susceptibility testing includes the use of a(n):

The concentrations in a broth dilution test that separate the categories of susceptible,intermediate,and resistant are called: