Deck 32: Cardiovascular System

Question 1

Veins carry blood that is

A) oxygen poor, CO₂ rich.
B) oxygen poor, CO₂ poor.
C) oxygen rich, CO₂ poor.
D) oxygen rich, CO₂ rich.

Answer 1

oxygen poor, CO₂ rich.

Question 2

Which of the following is considered a potential source of an intravascular infection?

A) Pneumonia due to Streptococcus pneumoniae
B) Artificial heart valve
C) Decubitus ulcer
D) Urinary catheter

Answer 2

Artificial heart valve

Question 3

A potentially fatal systemic response to the presence of organisms in the bloodstream is called

A) septicemia.
B) sepsis.
C) endocarditis.
D) septic shock.

Answer 3

septic shock.

Question 4

Individuals who lack a spleen are especially susceptible to infection with organisms that are

A) normal oral flora.
B) considered unusual isolates.
C) encapsulated.
D) the causative agents of urinary tract infections.

Question 5

Meningitis can be accompanied by __________________ bacteremia.

A) transient
B) intermittent
C) continuous
D) relapsing

Question 6

Which of the following organisms is most likely to trigger septic shock?

A) Beta-hemolytic, indole-positive, lactose-fermenting, gram-negative rod
B) Beta-hemolytic, catalase- and coagulase-positive, gram-positive coccus
C) Nonhemolytic, catalase-negative, esculin- and PYR-positive, gram-positive coccus
D) Gram-negative rod that is ALA and horse blood agar positive

Question 7

Subacute bacterial endocarditis is most often caused by

A) gamma-hemolytic, catalase-positive, coagulase-negative, gram-positive cocci.
B) gamma-hemolytic, catalase-negative, ESC/PYR +/+, gram-positive cocci.
C) beta-hemolytic, catalase-negative, bacitracin-susceptible, gram-positive cocci.
D) gamma-hemolytic, catalase-negative, ESC/PYR - /- , gram-positive cocci.

Question 8

A 78-year-old female is hospitalized with complications due to hip replacement surgery. She is receiving intravenous antibiotics and oxygen via a nasal cannula as well as having a urinary catheter in place. At four days of hospitalization, she develops fever after showing signs of improvement. The physician suspects bacteremia. To prove his suspicion, he orders a culture of her

A) blood.
B) skin surface at the site of the intravenous catheter insertion.
C) intravenous catheter tip.
D) a and b.
E) a and c.

Question 9

A 27-year-old female, at 11 weeks gestation, is suffering from severe vomiting and nausea. She is unable to eat or drink. Her physician admits her to treat the developing dehydration. The patient has an intravenous catheter line placed, and she is given parenteral nutrition supplemented with lipids. She developed a fever, and two sets of blood cultures were drawn through the IV catheter. After 48 hours in the automated blood culture detection system, all four blood culture bottles were positive with budding yeast. The bottles were subcultured to chocolate and Sabouraud dextrose agars. Both agar plates were no growth at 24 hours. At 48 hours, pinpoint colonies were observed on both agar plates. The physician decides to pull the intravenous catheter, and it is sent to the laboratory for culture. To help the suspected organism grow better, you will roll it on a

A) corn meal agar.
B) Sabouraud dextrose agar supplemented with olive oil.
C) chocolate agar supplemented with vitamin B₆.
D) sheep blood agar and incubate in a capnophilic atmosphere.

Question 10

A 64-year-old female was admitted for removal of a ruptured appendix. Her medical history was unremarkable except for a case of rheumatic fever as a child that left her with an audible heart murmur. Three months after the surgery, she saw her physician complaining of fever, chills, fatigue, and dizziness for several weeks. The physician noted that her heart murmur was much more pronounced. He ordered two sets of blood cultures to be drawn. Both sets of blood cultures grow gram-positive cocci in pairs and chains. The gray, gamma-hemolytic colony is catalase negative. It hydrolyzes esculin in the presence of bile and grows in 6.5% salt broth. Given this patient history the infectious disease present is

A) Septic shock
B) Transient bacteremia
C) Subacute bacterial endocarditis
D) Acute bacterial endocarditis

Question 11

A 78-year-old male develops osteomyelitis after hip replacement surgery. After four weeks of antibiotics, he is sent home with two more weeks of intravenous antibiotics. On week 5, he develops a fever, and three sets of blood cultures are drawn. At 24 hours, the organism observed in the image provided was present in four of six bottles.
Source: CDC and Dr. W. Kaplan
The organism grows as a pinpoint haze on sheep blood and chocolate agars but not on
MacConkey and reducible blood agars. Infection with this organism was probably due to

A) antibiotic use.
B) the presence of an artificial hip.
C) a urinary catheter.
D) the presence of an IV catheter.

Question 12

A 17-year-old female exhibits signs of disseminated gonorrhea. A total of 6 mL of blood was drawn and divided between two bottles of blood culture broth with SPS, each containing a volume of 40 mL. While her endocervical culture grows Neisseria gonorrhoeae, her blood cultures remain negative. What is the explanation for the lack of growth in the blood culture vials?

A) Sucrose was not added and the organisms need a hyperosmotic solution to survive.
B) Too little blood was drawn in the vials and organism growth was inhibited.
C) Blood culture bottles with resin beads should have been used for blood collection.
D) Blood culture bottles with heparin should have used for blood collection.

Question 13

Which of the following disease states may be detected with only the collection of one blood culture set?

A) Endocarditis
B) Intravenous catheter? related sepsis
C) Bacteremia after teeth cleaning
D) Pseudobacteremia

Question 14

The lysis-centrifugation method for processing blood cultures is able to accomplish all of the following except

A) decrease contamination rate.
B) provide for better recovery of Streptococcus pneumoniae.
C) reduce the time to detection of Brucella spp.
D) increase recovery of fungi.

Question 15

One advantage of continuous monitoring blood culture systems are used in most clinical microbiology laboratories because of

A) less manipulation of positive bottles.
B) decreased cost.
C) faster detection of organisms.
D) the ability to detect all microorganisms.

Question 16

An intravenous catheter is removed from an 83-year-old male hospitalized with cancer and sent to the laboratory for culture. The tip is rolled across the surface of a sheep blood agar. At 24 hours incubation, 20 colonies of white, gamma-hemolytic, gram-positive cocci are isolated. The organism proved to be catalase positive and tube coagulase negative. This organism

A) is a skin contaminant.
B) indicates a catheter-related infection.
C) cannot be assessed without the results of a blood culture drawn at the same time.
D) is considered a critical value and should be reported STAT.

Question 17

A set of blood culture bottles is drawn. At 48 hours, the anaerobic bottle is positive with the organism in the image provided.
Source: CDC and Dr. Jack Poland
You would subculture this positive blood culture bottle to
1) sheep blood agar.
2) chocolate agar.
3) MacConkey agar.
4) phenylethyl alcohol agar.
5) reducible blood agar

A) 1, 2, 3, and 5
B) 2, 3, 4, and 5
C) 1, 3, 4, and 5
D) 1, 2, 3, and 4

Question 18

Three patients from the burn unit have positive blood cultures that grow an oxidase-positive, non-lactose fermenting, gram-negative rod that is TSI - K/NC and lysine positive. This presence of this organism in all three patients suggests

A) an outbreak of nosocomial infection.
B) the presence of infected intravenous catheters.
C) burn wound infection.
D) an outbreak of pseudobacteremia.

Question 19

Incubation of blood cultures for up to 30 days is recommended for the recovery of

A) Leptospira interrogans.
B) Brucella spp.
C) Bartonella spp.
D) fungi.

Question 20

Which of the following scenarios best correlates with the isolation of Aggregatibacter aphrophilus in blood cultures?

A) 17-year-old male with leukemia who was in a fistfight
B) 54-year-old female with colon cancer
C) 20-year-old male with a heart murmur who got his tongue pierced
D) 34-year-old female who had a tooth pulled