Deck 21: Pseudomonas, Burkholderia, and Similar Organisms

Question 1

Which best describes the source of Burkholderia cepacia infections?

A)Plants, soil, and water
B)Medical devices medical solutions
C)Contaminated foods
D)None of the above are correct.
E)All of the above are correct.

Answer 1

E
Plants, soil, and water serve as reservoirs of Burkholderia cepacia. This organism is able to survive on or in medical devices and disinfectants. Human acquisition of B. cepacia resulting in colonization or infection usually involves direct contact with contaminated foods; medical solutions, including disinfectants; and devices, such as respiratory equipment. Alternatively, person-to-person transmission also has been documented.

Question 2

A convenient and reliable identification scheme for P.aeruginosa involves the following conventional tests:

A)Oxidase, TSI slant, growth at 42° C on Mueller-Hinton agar or trypticase soy agar
B)Catalase, LIA slant, growth at 42° C on Mueller-Hinton agar or trypticase soy agar
C)Oxidase, TSI slant, growth at 24° C on Mueller-Hinton agar or trypticase soy agar
D)Catalase, TSI slant, growth at 42° C on sheep blood agar or blood trypticase soy agar

Answer 2

A
Pseudomonas aeruginosa is one of the most common gram-negative species encountered in the clinical setting. A convenient and reliable identification scheme for this pathogen is helpful and includes the oxidase test, TSI slant, testing for growth at 42° C, and observation of bright bluish-green, red, or brown diffusible pigment.

Question 3

Of the species of Burkholderia, which is the one most commonly found in clinical specimens?

A)Burkholderia ralstonia
B)Burkholderia pseudomallei
C)Burkholderia mallei
D)Burkholderia cepacia

Answer 3

D
B. cepacia is the one most commonly found in clinical specimens. This organism is able to survive on or in medical devices and disinfectants. Intrinsic resistance to multiple antimicrobial agents also contributes to the organism's survival in hospitals.

Question 4

The disease referred to as melioidosis is caused by

A)Pseudomonas aeruginosa.
B)Ralstonia pickettii.
C)Burkholderia mallei.
D)Burkholderia pseudomallei.

Question 5

Excluding Enterobacteriaceae, name the second most common gram-negative bacilli encountered in clinical specimens.

A)Pseudomonas
B)Burkholderia
C)Ralstonia
D)Vibrio

Question 6

An organism described as oxidase-positive, TSI slant with an alkaline/no change, good growth at 42° C, and producing bright bluish green pigment on Mueller-Hinton agar is most likely

A)Pseudomonas aeruginosa.
B)Ralstonia pickettii.
C)Burkholderia mallei.
D)Burkholderia pseudomallei.

Question 7

In the clinical setting, Pseudomonas aeruginosa is the most commonly encountered gram-negative species that is not a member of the family Enterobacteriaceae. This organism survives in various environments in nature and in homes and hospitals.
Production of exotoxin A, which kills host cells by inhibiting protein synthesis, and production of several proteolytic enzymes and hemolysins that destroy cells and tissue are factors that contribute to pathogenicity of

A)Pseudomonas aeruginosa.
B)Burkholderia cepacia.
C)Ralstonia pickettii.
D)Burkholderia mallei.

Question 8

All Brevundimonas, Burkholderia, Ralstonia, Pseudomonas, and Acidovorax share which of the following characteristics?

A)Oxidase-positive
B)Utilize glucose oxidatively
C)Able to grow on MacConkey agar
D)None of the above are correct.
E)All of the above are correct.