Specimen Collection & Transport (Microbiology)

Question 1

The proper blood-to-broth ratio for blood cultures to reduce the antibacterial effect of serum in adults is:

A) 1:2
B) 1:3
C) 1:10
D) 1:30

Answer 1

C) 1:10

Question 2

The most appropriate method for collecting a urine specimen from a patient with an indwelling catheter is:

A) remove the catheter, cut the tip, and submit it for culture
B) disconnect the catheter from the bag, and aseptically collect urine from the terminal end of the catheter
C) aseptically collect urine directly from the drainage bag
D) aspirate urine aseptically from the catheter tubing

Answer 2

D) aspirate urine aseptically from the catheter tubing

Question 3

Which of the following groups of specimens would be acceptable for anaerobic culture?

A) vaginal swab, eye swab
B) intraoral surface swab, leg tissue
C) pleural fluid, brain abscess fluid
D) urine, sputum

Answer 3

C) pleural fluid, brain abscess fluid

Question 4

Sodium polyanetholsufonate (SPS) is used as an anticoagulant for blood cultures because it:

A) inactivates penicillin and cephalosporins
B) prevents clumping of red cells
C) inactivates neutrophils and components of serum complement
D) facilitates growth of anaerobes

Answer 4

C) inactivates neutrophils and components of serum complement

Question 5

The optimal collection of a wound specimen for culture of anaerobic organisms is a:

A) swab of lesion obtained before administration of antibiotics
B) swab of lesion obtained after administration of antibiotics
C) syringe filled with pus, obtained before administration of antibiotics
D) syringe filled with pus, obtained after administration of antibiotics

Answer 5

C) syringe filled with pus, obtained before administration of antibiotics

Question 6

The most important variable in the recovery of organisms in adult patients with bacteremia (bacterial sepsis) is:

A) subculture of all bottles at day 5 of incubation
B) the recommended volume of blood cultured
C) collection of daily blood culture sets for 3 consecutive days
D) collection of multiple blood culture sets from a single venipuncture

Answer 6

B) the recommended volume of blood cultured

Question 7

Virus transport medium should contain agents that:

A) enable rapid viral growth during the transport time
B) inhibit bacterial and fungal growth
C) destroy nonpathogenic viruses
D) inhibit complement-fixing antibodies

Answer 7

B) inhibit bacterial and fungal growth