ASCP 2023 exam Flashcards
Which one of the following anaerobes is inhibited by sodium polyanethol sulfonate (SPS)?
Peptostreptococcus anaerobius
A common cause of acute exudative pharyngitis is:
Streptococcus pyogenes
Polyvinyl alcohol used in the preparation of permanently stained smears of fecal material:
serves as an adhesive
The characteristic that is most commonly associated with the presence of strict anaerobic bacteria and can be taken as presumptive evidence of their presence in a clinical specimen is the
presence of a foul, putrid odor from tissue specimens and cultures
What stain is most often used as a screening stain when mycobacteria is suspected in a respiratory specimen?
auramine O
Which organism is the most common anaerobic bacteria isolated from infectious processes of soft tissue and anaerobic bacteremia?
B. fragilis
The primary isolation of Neisseria gonorrhoeae requires:
CO2
Shigella species characteristically are
nonmotile
In reviewing the number of Mycobacterium isolates for the current year, it is noted that there were 76% fewer isolates than the previous year (115 vs 28). The technologist in charge of the area has documented that the quality control of media, reagents and stains has been acceptable and there has been no gross contamination of the cultures noted. The most appropriate next course of action is to:
review the digestion and decontamination procedure
Which organism is predominantly responsible for visceral larva migrans?
Toxocara canis
which one of the following organisms could be used as the positive quality control test for lecithinase on egg yolk agar?
Clostridium perfringens
Organisms that are part of the Mycobacterium tuberculosis complex (MTBC) include Mycobacterium tuberculosis and:
M. africanum and M. bovis
A positive niacin test is characteristic of Mycobacterium:
tuberculosis
Small protozoan cysts are found in a wet mount of sediment from ethyl-acetate concentrated material. Each cyst has 4 nuclei that do not have peripheral chromatin, and each nucleus has a large karyosome, which appears as a refractive dot. These oval cysts are most likely
Endolimax nana
Which DNase-positive organism’s colony is not easily broken up and therefore displays the “hockey puck” characteristic, where it can be pushed across the plate of medium?
Moraxella catarrhalis
A reliable test for distinguishing Staphylococcus aureus from other staphylococci is:
coagulase
Which type of virus causes severe acute respiratory syndrome?
coronavirus
A young girl cuts her foot on a rock while swimming in the ocean. Her foot begins to show signs of infection, and her parents take her to the ER. A culture grows non-lactose fermenting gram-negative bacilli that produce copious amounts of hydrogen sulfide and gas, is indole-positive and motile. The organism most likely isolated is:
Edwardsiella species
Which one of the following clinical syndromes is associated with VZV infection?
shingles
Anaerobic, box-car shaped, beta-hemolytic gram-positive bacilli isolated from a foot wound are most likely:
Clostridium perfringens
A method to culture Acanthamoeba species from corneal ulcer scrapings is to inoculate:
an agar plate overlaid with Escherichia coli
An isolate on chocolate agar from a patient with epiglottitis is suggestive of Haemophilus species. Additional testing shows that the isolate required NAD for growth and is nonhemolytic. The organism is most likely Haemophilus:
parainfluenzae
What precaution should be taken to prevent infection of laboratory personnel when processing specimens for mycobacterial culture?
process all specimens in a biological safety hood
Group B, beta-hemolytic streptococci may be distinguished from other hemolytic streptococci by which of the following procedures?
latex antigen grouping