問題1
A clinical microbiology laboratory is preparing a Gram stain of a mixed bacterial culture containing both Gram-positive and Gram-negative organisms. The correct order of reagents used in the Gram staining procedure is:
A clinical microbiology laboratory is preparing a Gram stain of a mixed bacterial culture containing both Gram-positive and Gram-negative organisms. The correct order of reagents used in the Gram staining procedure is:
正確答案: B
問題2
A research team is investigating the host immune response to Mycobacterium tuberculosis. They discover that a specific mycobacterial glycolipid inhibits the maturation of phagosomes containing the bacteria, preventing their fusion with lysosomes. This mechanism allows M. tuberculosis to:
A research team is investigating the host immune response to Mycobacterium tuberculosis. They discover that a specific mycobacterial glycolipid inhibits the maturation of phagosomes containing the bacteria, preventing their fusion with lysosomes. This mechanism allows M. tuberculosis to:
正確答案: C
問題3
A centrifuge rotor containing capped tubes of sputum concentrate for AFB culture breaks during operation inside a Class II Biological Safety Cabinet (BSC). What is the most appropriate immediate action for the technologist?
A centrifuge rotor containing capped tubes of sputum concentrate for AFB culture breaks during operation inside a Class II Biological Safety Cabinet (BSC). What is the most appropriate immediate action for the technologist?
正確答案: C
問題4
An outbreak of gastroenteritis occurs among attendees of a company picnic. Epidemiological investigation points towards contaminated potato salad. Stool cultures from affected individuals grow non-lactose fermenting, Gram-negative rods that are H2S positive on TSI agar. Which pathogen is most likely responsible?
An outbreak of gastroenteritis occurs among attendees of a company picnic. Epidemiological investigation points towards contaminated potato salad. Stool cultures from affected individuals grow non-lactose fermenting, Gram-negative rods that are H2S positive on TSI agar. Which pathogen is most likely responsible?
正確答案: A
問題5
A microbiology laboratory is asked to identify the causative agent of a fungal keratitis. Microscopic examination of corneal scrapings reveals broad, aseptate hyphae with right-angle branching. The MOST likely genus is:
A microbiology laboratory is asked to identify the causative agent of a fungal keratitis. Microscopic examination of corneal scrapings reveals broad, aseptate hyphae with right-angle branching. The MOST likely genus is:
正確答案: C
問題6
A clinical microbiology laboratory is performing Gram staining on a sputum sample. After adding the crystal violet stain, a delay in the washing step with decolorizer (alcohol-acetone) would MOST likely result in:
A clinical microbiology laboratory is performing Gram staining on a sputum sample. After adding the crystal violet stain, a delay in the washing step with decolorizer (alcohol-acetone) would MOST likely result in:
正確答案: B
問題7
During the processing of stool specimens for ova and parasite examination, the formalin-ethyl acetate concentration procedure primarily serves to:
During the processing of stool specimens for ova and parasite examination, the formalin-ethyl acetate concentration procedure primarily serves to:
正確答案: B
問題8
A clinical microbiology laboratory is performing antimicrobial susceptibility testing on a Streptococcus pneumoniae isolate using broth microdilution. The lowest concentration of antibiotic that inhibits visible growth of the organism is reported as the:
A clinical microbiology laboratory is performing antimicrobial susceptibility testing on a Streptococcus pneumoniae isolate using broth microdilution. The lowest concentration of antibiotic that inhibits visible growth of the organism is reported as the:
正確答案: A
問題9
Which virus is recognized as the leading cause of sporadic, severe gastroenteritis in infants and young children globally, for which effective vaccines are now available?
Which virus is recognized as the leading cause of sporadic, severe gastroenteritis in infants and young children globally, for which effective vaccines are now available?
正確答案: B
問題10
The direct fluorescent antibody (DFA) test is commonly used for the rapid detection of which respiratory pathogen directly from nasopharyngeal specimens?
The direct fluorescent antibody (DFA) test is commonly used for the rapid detection of which respiratory pathogen directly from nasopharyngeal specimens?
正確答案: D
問題11
A patient develops a febrile illness with a diffuse petechial rash after a camping trip. Serological testing reveals a four-fold rise in antibody titer to Rickettsia rickettsii. The vector responsible for transmitting this organism is a:
A patient develops a febrile illness with a diffuse petechial rash after a camping trip. Serological testing reveals a four-fold rise in antibody titer to Rickettsia rickettsii. The vector responsible for transmitting this organism is a:
正確答案: B
問題12
A microbiology laboratory is investigating an outbreak of bloodstream infections in a neonatal intensive care unit. Isolates of Staphylococcus epidermidis from multiple infants show indistinguishable banding patterns by pulsed-field gel electrophoresis (PFGE). This finding MOST strongly suggests:
A microbiology laboratory is investigating an outbreak of bloodstream infections in a neonatal intensive care unit. Isolates of Staphylococcus epidermidis from multiple infants show indistinguishable banding patterns by pulsed-field gel electrophoresis (PFGE). This finding MOST strongly suggests:
正確答案: C
問題13
A researcher is investigating the mechanism of action of a novel antibacterial agent that inhibits bacterial protein synthesis. The agent binds to the 50S ribosomal subunit and prevents the translocation of peptidyl- tRNA. This mechanism of action is similar to which of the following antibiotics?
A researcher is investigating the mechanism of action of a novel antibacterial agent that inhibits bacterial protein synthesis. The agent binds to the 50S ribosomal subunit and prevents the translocation of peptidyl- tRNA. This mechanism of action is similar to which of the following antibiotics?
正確答案: C
問題14
A patient with a history of intravenous drug use develops a bloodstream infection with Enterococcus faecalis.
Antimicrobial susceptibility testing reveals resistance to vancomycin. The MOST likely mechanism of vancomycin resistance in Enterococcus involves:
A patient with a history of intravenous drug use develops a bloodstream infection with Enterococcus faecalis.
Antimicrobial susceptibility testing reveals resistance to vancomycin. The MOST likely mechanism of vancomycin resistance in Enterococcus involves:
正確答案: A
問題15
A patient with a history of solid organ transplantation develops diarrhea and abdominal cramps. Stool studies are negative for bacterial pathogens and C. difficile toxins. Colonoscopy reveals characteristic cytomegalic inclusion bodies in colonic biopsies. The MOST likely causative agent is:
A patient with a history of solid organ transplantation develops diarrhea and abdominal cramps. Stool studies are negative for bacterial pathogens and C. difficile toxins. Colonoscopy reveals characteristic cytomegalic inclusion bodies in colonic biopsies. The MOST likely causative agent is:
正確答案: B