Question 1

How should quality control testing occur?

Accepted Answer

A) One specified microbiologist should use extreme care when doing quality control testing, using special pipettes, special agar plates, and special incubators. 
B) The procedure should be followed to a T, and if any mistake is made, the test should be discarded and started again. 
C) The microbiology supervisor should perform all quality control testing. 
D) Quality control testing should be included in all the patients tested and treated like a patient specimen. 
A) One specified microbiologist should use extreme care when doing quality control testing, using special pipettes, special agar plates, and special incubators. 
B) The procedure should be followed to a T, and if any mistake is made, the test should be discarded and started again. 
C) The microbiology supervisor should perform all quality control testing. 
D) Quality control testing should be included in all the patients tested and treated like a patient specimen. D

Question 2

Spontaneous mutations occur in the b-lactamase genes that result in extended-spectrum b-lactamases (ESBL).These ESBL inactivate:

Accepted Answer

A) cephalosporins. 
B) penicillins. 
C) aztreonam. 
D) all of the above. 
A) cephalosporins. 
B) penicillins. 
C) aztreonam. 
D) all of the above. D

Question 3

The minimum bactericidal concentration (MBC) test differs from the minimal inhibitory concentration (MIC) test because the MIC test gives the concentration needed at the site of infection to inhibit bacterial multiplications, whereas the MBC gives:

Accepted Answer

A) the highest concentration of antimicrobial that will kill an organism. 
B) the amount of antimicrobial that must be achieved at the infection site to inhibit the organism. 
C) the amount of antimicrobial that must be achieved at the infection site to kill the organism. 
D) none of the above. 
A) the highest concentration of antimicrobial that will kill an organism. 
B) the amount of antimicrobial that must be achieved at the infection site to inhibit the organism. 
C) the amount of antimicrobial that must be achieved at the infection site to kill the organism. 
D) none of the above. C

Question 4

Agar dilution and disk diffusion tests for Streptococcus pneumoniae and Streptococcus spp.use:

Accepted Answer

A) Mueller-Hinton agar supplemented with X and V factors. 
B) Columbia base supplemented with 5% sheep blood. 
C) trypticase soy agar base supplemented with 5% lysed horse blood. 
D) Mueller-Hinton agar supplemented with 5% sheep blood. 
A) Mueller-Hinton agar supplemented with X and V factors. 
B) Columbia base supplemented with 5% sheep blood. 
C) trypticase soy agar base supplemented with 5% lysed horse blood. 
D) Mueller-Hinton agar supplemented with 5% sheep blood.

Question 5

In terms of MIC microdilution trays, a skipped well occurs when:

Accepted Answer

A) a well on the tray is skipped with inoculum and it does not grow. 
B) the inoculator is turned around and the sterility well is accidentally inoculated and the growth well is accidentally skipped. 
C) there is growth at higher concentrations and no growth at one or more of the lower concentration wells. 
D) none of the above. 
A) a well on the tray is skipped with inoculum and it does not grow. 
B) the inoculator is turned around and the sterility well is accidentally inoculated and the growth well is accidentally skipped. 
C) there is growth at higher concentrations and no growth at one or more of the lower concentration wells. 
D) none of the above.

Question 6

Important factors that must be considered when determining whether antimicrobial susceptibility testing is warranted include:

Accepted Answer

A) the body site from which the organism was isolated. 
B) the presence of other bacteria and the quality of the specimen from which the organism was grown. 
C) the host's status. 
D) all the above. 
A) the body site from which the organism was isolated. 
B) the presence of other bacteria and the quality of the specimen from which the organism was grown. 
C) the host's status. 
D) all the above.

Question 7

What concentrations of antibiotics are typically tested in minimal inhibitory concentrations (MICs)?

Accepted Answer

A) Serial fivefold dilution concentrations are tested. 
B) Serial tenfold dilution concentrations are tested. 
C) Serial onefold dilution concentrations are tested. 
D) Serial twofold dilution concentrations are tested. 
A) Serial fivefold dilution concentrations are tested. 
B) Serial tenfold dilution concentrations are tested. 
C) Serial onefold dilution concentrations are tested. 
D) Serial twofold dilution concentrations are tested.

Question 8

What is a breakpoint panel?

Accepted Answer

A) A standard minimal inhibitory concentration (MI
C)  panel that contains many more dilution wells for each drug tested 
B) An MIC panel with only three or four drugs tested 
C) An MIC panel with only one or a few concentrations of each drug 
D) An MIC panel that contains nonroutine drugs 
A) A standard minimal inhibitory concentration (MI
C)  panel that contains many more dilution wells for each drug tested 
B) An MIC panel with only three or four drugs tested 
C) An MIC panel with only one or a few concentrations of each drug 
D) An MIC panel that contains nonroutine drugs

Question 9

If the minimal inhibitory concentration (MIC) or zone size is interpreted as resistant using the latest Clinical and Laboratory Standards Institute (CLSI) tables:

Accepted Answer

A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial or more than can be achieved and for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above. 
A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial or more than can be achieved and for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above.

Question 10

When reading broth microdilution minimal inhibitory concentration (MIC) testing, the MIC for a particular drug is the _____ concentration showing _____ growth.

Accepted Answer

A) lowest; no obvious 
B) highest; no obvious 
C) lowest; confluent 
D) highest; confluent 
A) lowest; no obvious 
B) highest; no obvious 
C) lowest; confluent 
D) highest; confluent

Question 11

What is the most widely used method of inoculum standardization?

Accepted Answer

A) McFarland turbidity standards 
B) Remel inoculum standards 
C) Becton-Dickson standards 
D) Difco standards 
A) McFarland turbidity standards 
B) Remel inoculum standards 
C) Becton-Dickson standards 
D) Difco standards

Question 12

How long are minimal inhibitory concentration (MIC) panels for anaerobes incubated?

Accepted Answer

A) 24 Hours 
B) 36 Hours 
C) 48 Hours 
D) 72 Hours 
A) 24 Hours 
B) 36 Hours 
C) 48 Hours 
D) 72 Hours

Question 13

A combination of antimicrobials is said to show synergism if the antibacterial activity is _____ the single agents.

Accepted Answer

A) significantly greater than that of 
B) significantly less than that of 
C) sustained for a much prolonged time compared with 
D) sustained for a much shorter time compared with 
A) significantly greater than that of 
B) significantly less than that of 
C) sustained for a much prolonged time compared with 
D) sustained for a much shorter time compared with

Question 14

Oxacillin-resistant Staphylococcus aureus is called _____-resistant S.aureus.

Accepted Answer

A) methicillin 
B) oxacillin 
C) penicillin 
D) penicillinase 
A) methicillin 
B) oxacillin 
C) penicillin 
D) penicillinase

Question 15

What is the most critical step in any susceptibility test?

Accepted Answer

A) Plate streaking 
B) Organism isolation 
C) Gram stain identification 
D) Inoculum preparation 
A) Plate streaking 
B) Organism isolation 
C) Gram stain identification 
D) Inoculum preparation

Question 16

When the activity of the combination of antimicrobial agents is less than that of the single agents, we say the agents are:

Accepted Answer

A) synergistic. 
B) antagonistic. 
C) indifferent. 
D) uncomplicated. 
A) synergistic. 
B) antagonistic. 
C) indifferent. 
D) uncomplicated.

Question 17

If the minimal inhibitory concentration (MIC) or zone size is interpreted as intermediate using the latest Clinical and Laboratory Standards Institute (CLSI) tables:

Accepted Answer

A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial or more than can be achieved and for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above. 
A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial or more than can be achieved and for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above.

Question 18

If the minimal inhibitory concentration (MIC) or zone size is interpreted as susceptible using the latest CLSI tables:

Accepted Answer

A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above. 
A) the clinical interpretation of the result is that the patient's infecting organism should respond to therapy with that antimicrobial agent using the dosage normally recommended for that type of infection and that species. 
B) the patient's infecting organism is unlikely to be inhibited by the usually achievable concentrations of the antimicrobial agent based on the dosages normally used with that drug. 
C) the patient's infecting organism is likely to require the maximum amount of antimicrobial for which the clinical response is likely to be less than with a susceptible strain. 
D) none of the above.

Question 19

What antibiotics should be reported for urinary tract infections?

Accepted Answer

A) Group A antibiotics 
B) Group B antibiotics 
C) Urinary tract active agents 
D) Group C antibiotics 
A) Group A antibiotics 
B) Group B antibiotics 
C) Urinary tract active agents 
D) Group C antibiotics

Question 20

As a general guideline, it is suggested that within a particular antimicrobial class, primary (group A) agents should be reported first and secondary (group B) agents should be reported only if the:

Accepted Answer

A) physician insists that a secondary agent be reported. 
B) hospital pharmacy no longer stocks the group A agent. 
C) patient cannot tolerate the primary agents. 
D) FDA has recalled the primary agents. 
A) physician insists that a secondary agent be reported. 
B) hospital pharmacy no longer stocks the group A agent. 
C) patient cannot tolerate the primary agents. 
D) FDA has recalled the primary agents.

Exam 13: Antimicrobial Susceptibility Testing

How should quality control testing occur?

Spontaneous mutations occur in the b-lactamase genes that result in extended-spectrum b-lactamases (ESBL).These ESBL inactivate:

The minimum bactericidal concentration (MBC) test differs from the minimal inhibitory concentration (MIC) test because the MIC test gives the concentration needed at the site of infection to inhibit bacterial multiplications, whereas the MBC gives:

Agar dilution and disk diffusion tests for Streptococcus pneumoniae and Streptococcus spp.use:

In terms of MIC microdilution trays, a skipped well occurs when:

Important factors that must be considered when determining whether antimicrobial susceptibility testing is warranted include:

What concentrations of antibiotics are typically tested in minimal inhibitory concentrations (MICs)?

What is a breakpoint panel?

If the minimal inhibitory concentration (MIC) or zone size is interpreted as resistant using the latest Clinical and Laboratory Standards Institute (CLSI) tables:

When reading broth microdilution minimal inhibitory concentration (MIC) testing, the MIC for a particular drug is the _____ concentration showing _____ growth.

What is the most widely used method of inoculum standardization?

How long are minimal inhibitory concentration (MIC) panels for anaerobes incubated?

A combination of antimicrobials is said to show synergism if the antibacterial activity is _____ the single agents.

Oxacillin-resistant Staphylococcus aureus is called _____-resistant S.aureus.

What is the most critical step in any susceptibility test?

When the activity of the combination of antimicrobial agents is less than that of the single agents, we say the agents are:

If the minimal inhibitory concentration (MIC) or zone size is interpreted as intermediate using the latest Clinical and Laboratory Standards Institute (CLSI) tables:

If the minimal inhibitory concentration (MIC) or zone size is interpreted as susceptible using the latest CLSI tables:

What antibiotics should be reported for urinary tract infections?

As a general guideline, it is suggested that within a particular antimicrobial class, primary (group A) agents should be reported first and secondary (group B) agents should be reported only if the:

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

When reading broth microdilution minimal inhibitory concentration (MIC) testing, the MIC for a particular drug is the _ concentration showing _ growth.