8.3 Nonfermentative Bacilli Flashcards
What are the most appropriate screening tests to presumptively differentiate and identify the nonfermentative gram-negative bacilli (NFB) from the Enterobacteriaceae species?
A. Catalase, decarboxylation of arginine, growth on blood agar
B. Motility, urease, morphology on blood agar
C. Oxidase, TSI, nitrate reduction, growth on MacConkey agar
D. Oxidase, indole, and growth on blood agar
C. Oxidase, TSI, nitrate reduction, growth on MacConkey agar
Presumptive tests used for identification of the Pseudomonas spp. are:
A. Oxidase, oxidation–fermentation (OF) glucose (open), OF glucose (sealed), motility, pigment production
B. Growth on blood agar plate (BAP) and eosin–methylene blue (EMB) agars, lysine decarboxylation, catalase
C. Growth on MacConkey, EMB, and XLD agars and motility
D. Growth on mannitol salt agar and flagellar stain
A. Oxidase, oxidation–fermentation (OF) glucose (open), OF glucose (sealed), motility, pigment production
Which tests are most appropriate to differentiate between Pseudomonas aeruginosa and Pseudomonas putida?
A. Oxidase, motility, pyoverdin
B. Oxidase, motility, lactose
C. Oxidase, ONPG, DNase
D. Mannitol, nitrate reduction, growth at 42°C
D. Mannitol, nitrate reduction, growth at 42°C
Which test group best differentiates Acinetobacter spp. from P. aeruginosa?
A. Oxidase, motility, nitrate reduction
B. MacConkey growth, 37°C growth, catalase
C. Blood agar growth, oxidase, catalase
D. Oxidase, TSI, MacConkey growth
A. Oxidase, motility, nitrate reduction
In addition to motility, which test best differentiates Acinetobacter spp. and Alcaligenes faecalis?
A. Triple sugar iron agar
B. Oxidase
C. Urease
D. Flagellar stain
B. Oxidase
The most noted differences between P. aeruginosa and Stenotrophomonas maltophilia are:
A. Oxidase, catalase, and TSI
B. Oxidase, catalase, and ONPG
C. Oxidase, 42°C growth, and polar tuft of flagella
D. Catalase, TSI, and pigment
C. Oxidase, 42°C growth, and polar tuft of flagella
Which nonfermentative bacillus is usually associated with a lung infection related to cystic fibrosis (CF)?
A. Pseudomonas fluorescens
B. Pseudomonas aeruginosa
C. Pseudomonas putida
D. Burkholderia pseudomallei
B. Pseudomonas aeruginosa
A nonfermenter recovered from an eye wound is oxidase positive, motile with polar monotrichous flagella, and grows at 42°C. Colonies are dry, wrinkled or smooth, buff to light brown, and are difficult to remove from the agar. In which DNA homology group should this organism be placed?
A. Pseudomonas stutzeri
B. Pseudomonas fluorescens
C. Pseudomonas putida
D. Burkholderia pseudomallei
A. Pseudomonas stutzeri
Which organism is associated with immunodeficiency syndromes and melioidosis (a glanders-like disease prevalent in Southeast Asia and northern Australia)?
A. Pseudomonas aeruginosa
B. Pseudomonas stutzeri
C. Pseudomonas putida
D. Burkholderia pseudomallei
D. Burkholderia pseudomallei
Which characteristics/biochemical tests are used to differentiate Burkholderia cepacia from S. maltophilia?
A. Pigment on blood agar, oxidase, DNase
B. Pigment on MacConkey agar, flagellar stain, motility
C. Glucose, maltose, lysine decarboxylase
D. Triple-sugar iron agar, motility, oxidase
A. Pigment on blood agar, oxidase, DNase
The following results were obtained from a pure culture of gram-negative rods recovered from the pulmonary secretions of a 10-year-old cystic fibrosis patient with pneumonia:
Oxidase = + Motility = +
Glucose OF (open) = + Gelatin hydrolysis = +
Pigment = Red Arginine dihydrolase = + (nonfluorescent)
Growth at 42°C = + Flagella = + (polar, monotrichous)
Which is the most likely organism?
A. Burkholderia pseudomallei
B. Pseudomonas stutzeri
C. Burkholderia cepacia
D. Pseudomonas aeruginosa
D. Pseudomonas aeruginosa
Alcaligenes faecalis (formerly A. odorans) is distinguished from Bordetella bronchiseptica with which test?
A. Urease (rapid)
B. Oxidase
C. Growth on MacConkey agar
D. Motility
A. Urease (rapid)
Chryseobacterium spp. are easily distinguished from Acinetobacter spp. by which of the following two tests?
A. Oxidase, growth on MacConkey agar
B. Oxidase and OF (glucose)
C. TSI and urea hydrolysis
D. TSI and VP
A. Oxidase, growth on MacConkey agar
A gram-negative coccobacillus was recovered on chocolate agar from the CSF of an immunosuppressed patient. The organism was nonmotile and positive for indophenol oxidase but failed to grow on MacConkey agar. The organism was highly susceptible to penicillin. The most probable identification is:
A. Acinetobacter spp.
B. Pseudomonas aeruginosa
C. Pseudomonas stutzeri
D. Moraxella lacunata
D. Moraxella lacunata
Cetrimide agar is used as a selective isolation agar for which organism?
A. Acinetobacter spp.
B. Pseudomonas aeruginosa
C. Moraxella spp.
D. Stenotrophomonas maltophilia
B. Pseudomonas aeruginosa