Question 1

A primary tenet of antimicrobial therapy is to use:

Accepted Answer

A) the least toxic agents. 
B) the most cost-effective agents. 
C) the most clinically effective agents. 
D) all of the above. 
A) the least toxic agents. 
B) the most cost-effective agents. 
C) the most clinically effective agents. 
D) all of the above.

Question 2

What automated system was originally designed for use in outer space?

Accepted Answer

A) TREK ARIS 
B) MicroScan Walkaway SI 
C) BD Phoenix 
D) VITEK 
A) TREK ARIS 
B) MicroScan Walkaway SI 
C) BD Phoenix 
D) VITEK

Question 3

Who sets the criteria in the table of values that relates the diameter of the zone to a category of susceptibility in disk diffusion testing?

Accepted Answer

A) Centers for Disease Control and Prevention (CD
C)  
B) College of American Pathologists (CAP) 
C) Clinical and Laboratory Standards Institute (CLSI) 
D) Joint Commission on Accreditation of Healthcare Organizations (JCAHO) 
A) Centers for Disease Control and Prevention (CD
C)  
B) College of American Pathologists (CAP) 
C) Clinical and Laboratory Standards Institute (CLSI) 
D) Joint Commission on Accreditation of Healthcare Organizations (JCAHO)

Question 4

Goals of combination antimicrobial therapy include all the following except:

Accepted Answer

A) obtain broad-spectrum coverage. 
B) enhance antibacterial activity through synergistic interactions. 
C) minimize resistance development. 
D) ensure that at least one antimicrobial will obtain the minimum bactericidal concentration (MB
C)  at the infection site. 
A) obtain broad-spectrum coverage. 
B) enhance antibacterial activity through synergistic interactions. 
C) minimize resistance development. 
D) ensure that at least one antimicrobial will obtain the minimum bactericidal concentration (MB
C)  at the infection site.

Question 5

The BD Phoenix system uses what principle to measure bacterial growth in the susceptibility test wells?

Accepted Answer

A) Hydrolysis of a fluorogenic growth substrate 
B) Turbidimetric detection 
C) Carbon dioxide concentration 
D) Redox indicator system 
A) Hydrolysis of a fluorogenic growth substrate 
B) Turbidimetric detection 
C) Carbon dioxide concentration 
D) Redox indicator system

Question 6

The Clinical and Laboratory Standards Institute (CLSI) has published methods for susceptibility testing of several agents of potential bioterrorism, including Brucella anthracis, Yersinia pestis, Burkholderia mallei, B.pseudomallei, Francisella tularensis, and Brucella spp.How does CLSI suggest clinical laboratories perform antimicrobial susceptibility testing on these isolates?

Accepted Answer

A) Use the agar dilution technique. 
B) Use the Kirby-Bauer method. 
C) Use the minimal inhibitory concentration (MI
C)  plates. 
D) Do not attempt to perform antimicrobial susceptibility on any of these isolates; refer them to a public health laboratory equipped to handle them. 
A) Use the agar dilution technique. 
B) Use the Kirby-Bauer method. 
C) Use the minimal inhibitory concentration (MI
C)  plates. 
D) Do not attempt to perform antimicrobial susceptibility on any of these isolates; refer them to a public health laboratory equipped to handle them.

Question 7

A zone of inhibition is:

Accepted Answer

A) the area on the agar plate where the drug no longer diffuses into the agar. 
B) the area around the antibiotic disk where the bacteria cannot grow. 
C) the zone around the edge of the plate where the streaking does not cover the agar and bacterial growth is inhibited. 
D) all of the above. 
A) the area on the agar plate where the drug no longer diffuses into the agar. 
B) the area around the antibiotic disk where the bacteria cannot grow. 
C) the zone around the edge of the plate where the streaking does not cover the agar and bacterial growth is inhibited. 
D) all of the above.

Question 8

Two antibiotics are contraindicated in pediatric patients.They are:

Accepted Answer

A) erythromycin and Augmentin. 
B) cleocin and Zithromax. 
C) tetracycline and Ceclor. 
D) tetracycline and fluoroquinolones. 
A) erythromycin and Augmentin. 
B) cleocin and Zithromax. 
C) tetracycline and Ceclor. 
D) tetracycline and fluoroquinolones.

Question 9

Guidance for the development of a selective-reporting or cascade-reporting protocol for antibiotics is available from the:

Accepted Answer

A) Centers for Disease Control and Prevention (CD
C) . 
B) Clinical Laboratory and Standards Institute (CLSI). 
C) United States Army Medical Research Institute (USAMRII
D) . 
D) Food and Drug Administration (FD
A) . 
A) Centers for Disease Control and Prevention (CD
C) . 
B) Clinical Laboratory and Standards Institute (CLSI). 
C) United States Army Medical Research Institute (USAMRII
D) . 
D) Food and Drug Administration (FD
A) .

Question 10

How are antibiotics chosen for inclusion into laboratory antimicrobial testing protocols?

Accepted Answer

A) There are no set standards, because physicians demand which drugs they want tested for particular bugs each time an antimicrobial susceptibility test is performed. 
B) The Clinical and Laboratory Standards Institute (CLSI) recommends the drugs that should be tested and reported for each type of specimen. 
C) The institutional pharmacy and therapeutics committee sets the list of drugs that are used in their facility 
D) Both b and c 
A) There are no set standards, because physicians demand which drugs they want tested for particular bugs each time an antimicrobial susceptibility test is performed. 
B) The Clinical and Laboratory Standards Institute (CLSI) recommends the drugs that should be tested and reported for each type of specimen. 
C) The institutional pharmacy and therapeutics committee sets the list of drugs that are used in their facility 
D) Both b and c

Question 11

When testing Escherichia coli, Klebsiella spp., and Proteus mirabilis, which drug is mostly likely to indicate the presence of an extended-spectrum b-lactamases (ESBL)?

Accepted Answer

A) Aztreonam 
B) Cefpodoxime 
C) Ceftriaxone 
D) Ceftazidime 
A) Aztreonam 
B) Cefpodoxime 
C) Ceftriaxone 
D) Ceftazidime

Question 12

The inhibition zone size and minimal inhibitory concentration (MIC) interpretive criteria published by the Clinical and Laboratory Standards Institute (CLSI) are established by careful analysis of all of the following except:

Accepted Answer

A) microbiologic data. 
B) pharmacokinetic data. 
C) results of clinical studies during the phase before Food and Drug Administration (FD
A)  approval. 
D) pharmacodynamic data. 
A) microbiologic data. 
B) pharmacokinetic data. 
C) results of clinical studies during the phase before Food and Drug Administration (FD
A)  approval. 
D) pharmacodynamic data.

Question 13

A patient is admitted to the hospital with a diagnosis of endocarditis.Two separate blood cultures grow out viridans streptococci.The penicillin minimal inhibitory concentration (MIC) of the organism is 0.12 µg/mL.What antibiotic should the physician prescribe?

Accepted Answer

A) Penicillin 
B) Erythromycin 
C) Clindamycin 
D) Gentamicin 
A) Penicillin 
B) Erythromycin 
C) Clindamycin 
D) Gentamicin

Question 14

On a breakpoint panel, when there is growth in both wells, the isolate is:

Accepted Answer

A) susceptible. 
B) resistant. 
C) intermediate. 
D) none of the above. 
A) susceptible. 
B) resistant. 
C) intermediate. 
D) none of the above.

Question 15

Advantages of the commercial microdilution susceptibility test methods include all the following except:

Accepted Answer

A) more accurate results than manual methods. 
B) automated panel readers. 
C) the quantitative nature of a minimal inhibitory concentration (MI
C) . 
D) computerized data management systems. 
A) more accurate results than manual methods. 
B) automated panel readers. 
C) the quantitative nature of a minimal inhibitory concentration (MI
C) . 
D) computerized data management systems.

Question 16

Therapy of disseminated meningococcal infections and various types of gonococcal infections are:

Accepted Answer

A) hard to treat and require special b-lactamase tests. 
B) an important public health concern, so a full spectrum of antimicrobial susceptibility testing is always performed. 
C) generally empiric based on recommendations of Centers for Disease Control and Prevention (CD
C) . 
D) none of the above. 
A) hard to treat and require special b-lactamase tests. 
B) an important public health concern, so a full spectrum of antimicrobial susceptibility testing is always performed. 
C) generally empiric based on recommendations of Centers for Disease Control and Prevention (CD
C) . 
D) none of the above.

Question 17

The minimal inhibitory concentration (MIC) is the _____ antibiotic concentration to _____ the growth of an organism.

Accepted Answer

A) lowest; slow 
B) highest; slow 
C) lowest; inhibit 
D) highest; inhibit 
A) lowest; slow 
B) highest; slow 
C) lowest; inhibit 
D) highest; inhibit

Question 18

In the Kirby-Bauer test, what is used to grow streptococci that do not grow adequately on unsupplemented Mueller-Hinton agar?

Accepted Answer

A) Chocolate agar 
B) PEA agar 
C) Mueller-Hinton agar with 5% sheep blood 
D) Mueller-Hinton agar with 5% rabbit blood 
A) Chocolate agar 
B) PEA agar 
C) Mueller-Hinton agar with 5% sheep blood 
D) Mueller-Hinton agar with 5% rabbit blood

Question 19

All the following organisms often produce b-lactamase except:

Accepted Answer

A) Haemophilus influenzae. 
B) Neisseria gonorrhoeae. 
C) Moraxella catarrhalis. 
D) Neisseria meningitidis. 
A) Haemophilus influenzae. 
B) Neisseria gonorrhoeae. 
C) Moraxella catarrhalis. 
D) Neisseria meningitidis.

Question 20

What agencies develop the zone interpretive criteria?

Accepted Answer

A) Centers for Disease Control and Prevention (CD
C)  and U.S.Army Medical Research Institute (USAMRII
D)  
B) U.S.Food and Drug Administration (FD
A)  and CDC 
C) FDA and Clinical and Laboratory Standards Institute (CLSI) 
D) CLSI and CDC 
A) Centers for Disease Control and Prevention (CD
C)  and U.S.Army Medical Research Institute (USAMRII
D)  
B) U.S.Food and Drug Administration (FD
A)  and CDC 
C) FDA and Clinical and Laboratory Standards Institute (CLSI) 
D) CLSI and CDC

Exam 13: Antimicrobial Susceptibility Testing

A primary tenet of antimicrobial therapy is to use:

What automated system was originally designed for use in outer space?

Who sets the criteria in the table of values that relates the diameter of the zone to a category of susceptibility in disk diffusion testing?

Goals of combination antimicrobial therapy include all the following except:

The BD Phoenix system uses what principle to measure bacterial growth in the susceptibility test wells?

A zone of inhibition is:

Two antibiotics are contraindicated in pediatric patients.They are:

Guidance for the development of a selective-reporting or cascade-reporting protocol for antibiotics is available from the:

How are antibiotics chosen for inclusion into laboratory antimicrobial testing protocols?

When testing Escherichia coli, Klebsiella spp., and Proteus mirabilis, which drug is mostly likely to indicate the presence of an extended-spectrum b-lactamases (ESBL)?

The inhibition zone size and minimal inhibitory concentration (MIC) interpretive criteria published by the Clinical and Laboratory Standards Institute (CLSI) are established by careful analysis of all of the following except:

A patient is admitted to the hospital with a diagnosis of endocarditis.Two separate blood cultures grow out viridans streptococci.The penicillin minimal inhibitory concentration (MIC) of the organism is 0.12 µg/mL.What antibiotic should the physician prescribe?

On a breakpoint panel, when there is growth in both wells, the isolate is:

Advantages of the commercial microdilution susceptibility test methods include all the following except:

Therapy of disseminated meningococcal infections and various types of gonococcal infections are:

The minimal inhibitory concentration (MIC) is the _____ antibiotic concentration to _____ the growth of an organism.

In the Kirby-Bauer test, what is used to grow streptococci that do not grow adequately on unsupplemented Mueller-Hinton agar?

All the following organisms often produce b-lactamase except:

What agencies develop the zone interpretive criteria?

Bacterial Cell Structure, Physiology, Metabolism, and Genetics

Host-Parasite Interaction

The Laboratory Role in Infection Control

Control of Microorganisms

Performance Improvement in the Microbiology Laboratory

Specimen Collection and Processing

Microscopic Examination of Materials From Infected Sites

Use of Colony Morphology for the Presumptive Identification of Microorganisms

Biochemical Identification of Gram-Negative Bacteria

Immunodiagnosis of Infectious Diseases

Applications of Molecular Diagnostics

Antimicrobial Agent Mechanisms of Action and Resistance

Staphylococci

Streptococcus, Enterococcus, and Other Catalase-Negative, Gram-Positive Cocci

Aerobic Gram-Positive Bacilli

Neisseria Species and Moraxella Catarrhalis

Haemophilus and Other Fastidious Gram-Negative Bacilli

Enterobacteriaceae

Vibrio, Aeromonas, Plesiomonas, and Campylobacter Species

Nonfermenting and Miscellaneous Gram-Negative Bacilli

Anaerobes of Clinical Importance

The Spirochetes

Chlamydia, Rickettsia and Similar Organisms

Mycoplasma and Ureaplasma

Mycobacterium Tuberculosis and Nontuberculous Mycobacteria

Medically Significant Fungi

Diagnostic Parasitology

Clinical Virology

Agents of Bioterror and Forensic Microbiology

Biofilms: Architects of Disease

Upper and Lower Respiratory Tract Infections

Skin and Soft Tissue Infections

Gastrointestinal Infections and Food Poisoning

Infections of the Central Nervous System

Bacteremia and Sepsis

Urinary Tract Infections

Genital Infections and Sexually Transmitted Diseases

Infections in Special Populations

Zoonotic Diseases

Ocular Infections

Filters

The minimal inhibitory concentration (MIC) is the _ antibiotic concentration to _ the growth of an organism.