PART 2.2 Flashcards
Routine laboratory testing for Treponema pallidum involves:
A. Culturing
B. Serological analysis
C. Acid-fast staining
D. Gram staining
B. Serological analysis
Which of the following organisms is the cause of Lyme disease?
A. Treponema pallidum
B. Neisseria meningitidis
C. Babesia microti
D. Borrelia burgdorferi
D. Borrelia burgdorferi
Primary atypical pneumonia is caused by: A. Streptococcus pneumoniae B. Mycoplasma pneumoniae C. Klebsiella pneumoniae D. Mycobacterium tuberculosis
B. Mycoplasma pneumoniae
Which organism typically produces “fried-egg” colonies on agar within 1-5 days of culture from a genital specimen?
A. Mycoplasma hominis
B. Borrelia burgdorferi
C. Leptospira interrogans
D. Treponema pallidum
A. Mycoplasma hominis
A direct smear from a nasopharyngeal swab stained with Loeffler’s methylene blue stain showed various letter shapes and metachromatic granules. The most likely identification is:
A. Corynebacterium spp.
B. Nocardia spp.
C. Listeria spp.
D. Gradnerella spp.
A. Corynebacterium spp.
Which of the following is the best rapid, noncultural test to perform when Gradnerella vaginalis is suspected in a patient with vaginosis?
A. 10% KOH
B. 3% H2O2
C. 30% H2O2
D. All of these
A. 10% KOH
A gram-positive spore-forming bacillus growing on blood agar anaerobically produces a double zone of beta-hemolysis and is positive for lecithinase. What is the presumptive identification?
A. Bacteroides ureolyticus
B. Bacteroides fragilis
C. Clostridium perfringens
D. Clostridium difficile
C. Clostridium perfringens
Which spore type and location is found on C. tetani?
A. Round, terminal spores
B. Round, subterminal
C. Ovoid, subterminal spores
D. Oval, terminal spores
A. Round, terminal spores
Which Clostridium spp. is most often recovered from a wound infection with gas gangrene?
A. C. sporogenes
B. C. sordellii
C. C. novyi
D. C. perfringens
D. C. perfringens
A Gram stain smear taken from the periodontal pockets of a 30-year-old male with poor dental hygiene showed sulfur granules containing gram-positive rods (short diphtheroids and some unbranched filaments). Colonies on blood agar resembled “molar teeth” in formation. The most likely organism is: A. Actinomyces israelii B. Propionibacterium acnes C. Streptococcus intermedius D. Peptostreptococcus anaerobius
A. Actinomyces israelii
Mycobacteria stained with Ziehl-neelsen or Kinyuon methods using a methylene blue counterstain, are seen microscopically as:
A. Bright red rods against a blue background
B. Bright yellow rods against a yellow background
C. Orange-red rods against a black background
D. Bright blue rods against a pink background
A. Bright red rods against a blue background
Acid-fast staining of a smear prepared from a digested sputum showed slender, slightly curved, beaded red mycobacterial rods. Growth on Middlebrook 7H10 slants produced buff-colored microcolonies with a serpentine pattern after 14 days at 37 oC. Niacin and nitrate reduction tests were positive. What is the most probable presumptive identification?
A. Mycobacterium tuberculosis
B. Mycobacterium ulcerans
C. Mycobacterium kansasii
D. Mycobacterium avium complex
A. Mycobacterium tuberculosis
Which of the following mycobacteria produces pigmented colonies in the dark (is a scotochromogen)?
A. M. szulgai
B. M. kansasii
C. M. tuberculosis
D. All of these
A. M. szulgai
All of the following Mycobacterium spp. produce the enzyme required to convert niacin to niacin ribonucleotide except:
A. M. kansasii
B. M. tuberculosis
C. M. avium
D. All of these
B. M. tuberculosis
Which nonpathogenic Mycobacterium sp. is isolated most often from clinical specimens and is called the “tapwater bacillus”?
A. M. kansasii
B. M. avium
C. M. leprae
D. M. gordonae
D. M. gordonae
