Question 1

The BACTEC automated blood culture system detects organisms by monitoring a rise in carbon dioxide (CO₂)levels using which type of sensor?

Accepted Answer

A)  Fluorescence 
B)  Colorimetric 
C)  Isotopic 
D)  Saponin 
A)  Fluorescence 
B)  Colorimetric 
C)  Isotopic 
D)  Saponin A

Question 2

Granulicatella spp.and Abiotrophia spp.are dependent on which nutritional additive for optimal growth?

Accepted Answer

A)  Vitamin K 
B)  Vitamin B6 
C)  Vitamin B12 
D)  Vitamin D 
A)  Vitamin K 
B)  Vitamin B6 
C)  Vitamin B12 
D)  Vitamin D B

Question 3

A 76-year-old man with intermittent fevers has blood cultures drawn three times.The second set is positive and grew out of a Corynebacterium spp.This organism is considered:

Accepted Answer

A)  pathogenic. 
B)  virulent. 
C)  a contaminant. 
D)  normal flora. 
A)  pathogenic. 
B)  virulent. 
C)  a contaminant. 
D)  normal flora. C

Question 4

Saponin, polypropylene glycol, SPS, and ethylenediaminetetraacetic acid (EDTA)are all components in which blood culture system?

Accepted Answer

A)  BACTEC system 
B)  BacT/ALERT system 
C)  ESP system 
D)  Lysis centrifugation system 
A)  BACTEC system 
B)  BacT/ALERT system 
C)  ESP system 
D)  Lysis centrifugation system

Question 5

Brucella infections usually result in which type of bacteremia?

Accepted Answer

A)  Transient 
B)  Intermittent 
C)  Continuous 
D)  Spontaneous 
A)  Transient 
B)  Intermittent 
C)  Continuous 
D)  Spontaneous

Question 6

A patient who has an existing heart condition has dental surgery but neglects to inform her dentist of this disorder.She later develops endocarditis as a consequence of the procedure.Which of the following organisms most likely caused endocarditis?

Accepted Answer

A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Streptococcus mutans 
D)  Pseudomonas aeruginosa 
A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Streptococcus mutans 
D)  Pseudomonas aeruginosa

Question 7

Patients receiving lipid-supplemented parenteral nutrition are at risk for developing fungemia caused by which organism?

Accepted Answer

A)  Histoplasma capsulatum 
B)  Malassezia furfur 
C)  Coccidioides immitis 
D)  Candida albicans 
A)  Histoplasma capsulatum 
B)  Malassezia furfur 
C)  Coccidioides immitis 
D)  Candida albicans

Question 8

If tachyzoites are found circulating in blood, then the infection would be classified as a:

Accepted Answer

A)  parasitemia. 
B)  bacteremia. 
C)  viremia. 
D)  fungemia. 
A)  parasitemia. 
B)  bacteremia. 
C)  viremia. 
D)  fungemia.

Question 9

In the case of infants and small children, how much blood is usually drawn for bacterial culture?

Accepted Answer

A)  0.5 mL 
B)  1 mL 
C)  1 to 5 mL 
D)  No more than 10 mL 
A)  0.5 mL 
B)  1 mL 
C)  1 to 5 mL 
D)  No more than 10 mL

Question 10

A consequence of sepsis is disseminated intravascular coagulation (DIC), which is characterized by numerous small blood vessels becoming clogged with clotted blood and bleeding as a result of the depletion of coagulation factors.Although any circulating pathogen can cause DIC, it is most often a consequence of ________ sepsis.

Accepted Answer

A)  fungal 
B)  viral 
C)  gram-positive 
D)  gram-negative 
A)  fungal 
B)  viral 
C)  gram-positive 
D)  gram-negative

Question 11

The possibility of an abscess should be considered if this bacterial group is isolated in the blood:

Accepted Answer

A)  Clostridium septicum. 
B)  Bacteroides fragilis. 
C)  Streptococcus anginosus. 
D)  Aeromonas hydrophila. 
A)  Clostridium septicum. 
B)  Bacteroides fragilis. 
C)  Streptococcus anginosus. 
D)  Aeromonas hydrophila.

Question 12

A 36-year-old emergency medical technician (EMT)is exposed to a patient with brucellosis.Blood cultures are drawn from the EMT and reported as negative after 1 week.Which of the following statements explains this discrepancy?

Accepted Answer

A)  The blood culture system is most likely not correctly functioning. 
B)  Brucella does not grow in the blood. 
C)  The blood culture bottles are most likely expired. 
D)  The blood should have been incubated for a minimum of 3 weeks. 
A)  The blood culture system is most likely not correctly functioning. 
B)  Brucella does not grow in the blood. 
C)  The blood culture bottles are most likely expired. 
D)  The blood should have been incubated for a minimum of 3 weeks.

Question 13

Which virus found in the blood involves infecting certain T lymphocytes and possibly macrophages?

Accepted Answer

A)  Cytomegalovirus (CMV) 
B)  Epstein-Barr virus (EBV) 
C)  Rubella virus 
D)  Human immunodeficiency virus (HIV) 
A)  Cytomegalovirus (CMV) 
B)  Epstein-Barr virus (EBV) 
C)  Rubella virus 
D)  Human immunodeficiency virus (HIV)

Question 14

A 26-year-old woman who has a Gardnerella vaginalis infection becomes immunocompromised, which causes the organism to enter the bloodstream.She has several fever spikes; therefore blood cultures are drawn and placed in blood culture media containing sodium polyanethol sulfonate (SPS).After 5 days of incubation, the blood cultures are negative.Which of the following statements explains this discrepancy?

Accepted Answer

A)  G. vaginalis stays localized in the female genital tract and does not enter the bloodstream. 
B)  The blood culture media is most likely expired. 
C)  The automated blood culture system is most likely not correctly functioning. 
D)  G. vaginalis is usually inhibited by this anticoagulant, making recovery difficult. 
A)  G. vaginalis stays localized in the female genital tract and does not enter the bloodstream. 
B)  The blood culture media is most likely expired. 
C)  The automated blood culture system is most likely not correctly functioning. 
D)  G. vaginalis is usually inhibited by this anticoagulant, making recovery difficult.

Question 15

The most common portal of entry for bacteremia is:

Accepted Answer

A)  the genitourinary tract. 
B)  the respiratory tract. 
C)  an abscess. 
D)  the biliary tract. 
A)  the genitourinary tract. 
B)  the respiratory tract. 
C)  an abscess. 
D)  the biliary tract.

Exam 67: Bloodstream Infections

The BACTEC automated blood culture system detects organisms by monitoring a rise in carbon dioxide (CO₂)levels using which type of sensor?

Granulicatella spp.and Abiotrophia spp.are dependent on which nutritional additive for optimal growth?

A 76-year-old man with intermittent fevers has blood cultures drawn three times.The second set is positive and grew out of a Corynebacterium spp.This organism is considered:

Saponin, polypropylene glycol, SPS, and ethylenediaminetetraacetic acid (EDTA)are all components in which blood culture system?

Brucella infections usually result in which type of bacteremia?

A patient who has an existing heart condition has dental surgery but neglects to inform her dentist of this disorder.She later develops endocarditis as a consequence of the procedure.Which of the following organisms most likely caused endocarditis?

Patients receiving lipid-supplemented parenteral nutrition are at risk for developing fungemia caused by which organism?

If tachyzoites are found circulating in blood, then the infection would be classified as a:

In the case of infants and small children, how much blood is usually drawn for bacterial culture?

The possibility of an abscess should be considered if this bacterial group is isolated in the blood:

A 36-year-old emergency medical technician (EMT)is exposed to a patient with brucellosis.Blood cultures are drawn from the EMT and reported as negative after 1 week.Which of the following statements explains this discrepancy?

Which virus found in the blood involves infecting certain T lymphocytes and possibly macrophages?

The most common portal of entry for bacteremia is:

Microbial Taxonomy

Bacterial Genetics, Metabolism, and Structure

Host-Microorganism Interactions

Laboratory Safety

Specimen Management

Role of Microscopy

Traditional Cultivation and Identification

Nucleic Acid-Based Analytic Methods for Microbial Identification and Characterization

Immunochemical Methods Used for Organism Detection

Serologic Diagnosis of Infectious Diseases

Principles of Antimicrobial Action and Resistance

Laboratory Methods and Strategies for Antimicrobial Susceptibility Testing

Staphylococcus Micrococcus and Similar Organisms

Streptococcus Enterococcus and Similar Organisms

Bacillus and Similar Organisms

Listeria Corynebacterium and Similar Organisms

Erysipelothrix Lactobacillus and Similar Organisms

Nocardia Streptomyces Rhodococcus and Similar Organisms

Enterobacteriaceae

Acinetobacter, Stenotrophomonas, and Other Organisms

Pseudomonas, Burkholderia, and Similar Organisms

Rhizobium, Ochrobactrum, and Similar Organisms

Chryseobacterium, Sphingobacterium, and Similar Organisms

Alcaligenes, Bordetella Nonpertussis, Comamonas, and Similar Organisms

Vibrio, Aeromonas, Chromobacterium, and Related Organisms

Sphingomonas Paucimobilis and Similar Organisms

Moraxella and Related Organisms

Eikenella and Similar Organisms

Pasteurella and Similar Organisms

Actinobacillus, Aggregatibacter, Kingella, Cardiobacterium, Capnocytophaga, and Similar Organisms

Haemophilus

Bartonella and Afipia

Campylobacter, Arcobacter, and Helicobacter

Legionella

Brucella

Bordetella Pertussis, Bordetella Parapertussis, and Related Species

Francisella

Streptobacillus Moniliformis and Spirillum Minus

Neisseria and Moraxella Catarrhalis

Overview and General Considerations

Overview of Anaerobic Organisms

Mycobacteria

Obligate Intracellular and Non-culturable Bacterial Agents

Cell Walldeficient Bacteria: Mycoplasma and Ureaplasma

The Spirochetes

Laboratory Methods for Diagnosis of Parasitic Infections: Overview

Intestinal Protozoa

Blood and Tissue Protozoa

Other Protozoa

Intestinal Nematodes Roundworms

Tissue Nematodes Roundworms

Blood and Tissue Filarialnematodes

Intestinal Cestodes

Tissue Cestodes

Intestinal Trematodes

Liver and Lung Trematodes

Blood Trematodes

Overview of Fungal Identification Methods and Strategies

Hyaline Molds, Mucorales Zygomycetes, Dermatophytes, and Opportunitistic and Systemic Mycoses

Dematiaceous Melanizedmolds

Opportunistic Atypical Fungus: Pneumocystis Jiroveci

The Yeasts

Anti-fungal Susceptibility Testing, Therapy, and Prevention

Overview of the Methods and Strategies in Virology

Viruses in Human Disease

Antiviral Therapy, Susceptibility Testing, and Prevention