NO.85 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?

NO.86 An immunocompromised patient returning from a trip to the southwestern United States presents with fever, cough, and chest pain. Chest X-ray shows diffuse pulmonary infiltrates. Sputum culture grows a dimorphic fungus that forms spherules containing endospores at 37°C. The MOST likely causative agent is:

NO.87 A research laboratory is investigating the mechanisms of viral latency in herpes simplex virus type 1 (HSV-
1). During latency in sensory neurons, the viral genome exists as a circular episome. Whichof the following viral gene products is thought to play a crucial role in maintaining this latent state and preventing viral gene expression?

NO.88 Metagenomic analysis of a bronchoalveolar lavage (BAL) sample from a patient with severe pneumonia reveals a complex microbial community with a high abundance of both bacterial and fungal sequences. This approach is particularly useful in identifying:

NO.89 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:

NO.90 A clinical microbiology laboratory is investigating a potential outbreak of a highly contagious respiratory virus. To rapidly screen a large number of nasopharyngeal swabs, the MOST appropriate initial diagnostic test would be:

NO.91 A patient with a history of recurrent Clostridioides difficile infection (CDI) is being considered for fecal microbiota transplantation (FMT). Pre-FMT screening of the donor stool sample should include comprehensive testing to exclude potential transmission of enteric pathogens. Which of the following would be the MOST critical to rule out in the donor stool?

NO.92 An elderly patient in a long-term care facility develops a localized outbreak of painful vesicles along a dermatome. Tzanck smear of a vesicle reveals multinucleated giant cells. The MOST likelycausative agent is:

NO.93 A clinical microbiology laboratory is performing quality control on antimicrobial susceptibility testing. The zone diameter for Escherichia coli ATCC 25922 tested against ciprofloxacin is consistently smaller than the acceptable range published by CLSI. The MOST likely cause of this discrepancy is:

NO.94 A research laboratory is developing a novel diagnostic assay for early detection of sepsis. They are investigating the use of host biomarkers that are rapidly upregulated in response to bacterial infection. Which of the following biomarkers has shown promise for differentiating between systemic inflammatory response syndrome (SIRS) and sepsis?

NO.95 A previously healthy 28-year-old female develops a severe, watery diarrhea after attending a picnic where she consumed potato salad that had been left unrefrigerated for several hours. Stool culture reveals numerous Gram-positive bacilli. Further biochemical testing shows the organism is beta-hemolytic on blood agar and produces a heat-stable enterotoxin. The MOST likely causative agent is:

NO.96 A clinical microbiology laboratory encounters a Gram-negative bacillus isolated from a bloodstream infection. The isolate exhibits resistance to multiple antibiotics, including carbapenems. Further phenotypic testing reveals the production of a metallo-beta-lactamase (MBL). Which of the following antibiotic combinations might still retain activity against this isolate?

NO.97 A patient with a history of neutropenia following chemotherapy develops a rapidly progressive pneumonia.
Bronchoalveolar lavage fluid reveals septate hyphae with acute angle (45-degree) branching. The MOST likely diagnosis is invasive pulmonary aspergillosis caused by:

NO.98 A patient develops a vesicular rash on their hands and feet, accompanied by fever and oral ulcers. The MOST likely causative agent is:

NO.99 A patient with a history of travel to South America presents with fever, lymphadenopathy, and hepatosplenomegaly. Peripheral blood smear reveals the presence of trypomastigotes. The MOST likely diagnosis is:

NO.100 A patient develops a severe, rapidly progressive pneumonia with hemoptysis. Gram stain of the sputum shows numerous small, pleomorphic Gram-negative coccobacilli. Growth on Bordet-Gengou agar is observed. The MOST likely causative agent is:

NO.101 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?