Free ASM-ABMM Exam Dumps Preview

A patient develops a severe gastrointestinal illness after consuming undercooked poultry. Stool culture yields a Gram-negative, microaerophilic, curved bacillus that is oxidase-positive. The MOST likely organism is:

A patient with a history of valvular heart disease undergoes a dental procedure and subsequently develops a bloodstream infection with Streptococcus mutans. This organism gains access to the bloodstream primarily due to:

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 patient with a history of intravenous drug use develops a bloodstream infection with Staphylococcus aureus. Antimicrobial susceptibility testing reveals resistance to methicillin. The mechanism of methicillin resistance in Staphylococcus aureus is primarily mediated by:

An immunocompromised patient develops a disseminated fungal infection. Tissue biopsy reveals small (2- 4 μm) yeast cells within macrophages. The patient has a history of living in the Ohio and Mississippi River valleys. The MOST likely causative agent is:

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:

A sputum sample from a patient with suspected pulmonary tuberculosis is submitted for AFB smear and culture. The smear is reported as positive for acid-fast bacilli (4+).

Which method is considered the gold standard for confirming the identification of Mycobacterium tuberculosis complex from culture?

A clinical microbiology laboratory is investigating a potential outbreak of Legionella pneumophila associated with a hospital's water system. The MOST appropriate environmental samples to collect for culture and comparison to clinical isolates would be:

A research laboratory is investigating the quorum sensing system in Pseudomonas aeruginosa. They identify a novel autoinducer molecule and a corresponding transcriptional regulator. Disruption of the gene encoding this regulator leads to a significant decrease in the production of virulence factors such as elastase and pyocyanin. Further analysis reveals that this regulator directly binds to the promoter regions of these virulence genes in the presence of the autoinducer. This regulatory mechanism is an example of:

A microbiology laboratory isolates a Gram-negative rod from a wound infection. The organism is oxidase-negative, ferments lactose on MacConkey agar, and produces indole. The MOST likely identification is:

A clinical laboratory receives a cerebrospinal fluid (CSF) sample from a 65-year-old patient presenting with fever, headache, and nuchal rigidity. Gram stain reveals Gram-positive cocci in pairs and short chains.
Culture on blood agar grows alpha-hemolytic colonies that are optochin-susceptible and bile soluble.

Which organism is most likely identified?

Vancomycin resistance in Enterococcus faecium, mediated by the vanA gene cluster, results from:

A microbiology laboratory receives a sample of cerebrospinal fluid from a patient with suspected bacterial meningitis. The Gram stain shows Gram-positive diplococci. Culture on blood agar shows alpha-hemolytic colonies that are bile soluble and optochin-sensitive. The MOST likely organism is:

A patient with a history of travel to a developing country presents with chronic diarrhea, abdominal pain, and weight loss. Stool examination reveals the presence of cysts containing four nuclei and chromatoidal bars with rounded ends. The MOST likely causative organism is:

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?

A clinical microbiology laboratory isolates a Gram-negative rod from a wound infection following a dog bite.
The organism grows on MacConkey agar, is oxidase-positive, and produces a characteristic bleach-like odor. The MOST likely identification is:

A patient with HIV infection and a CD4+ T-cell count below 50 cells/ develops a progressive neurological illness characterized by confusion, motor deficits, and seizures. Brain MRI reveals multiple white matter lesions without mass effect. PCR of the CSF is positive for JC virus. Thepathogenesis of this condition,
progressive multifocal leukoencephalopathy (PML), involves:

A patient with a history of chronic sinusitis develops a severe invasive fungal infection involving the nasal sinuses and extending into the orbit. Tissue biopsy reveals broad, aseptate hyphae with irregular

branching. The patient is diabetic and acidotic. The MOST likely causative organism belongs to the genus:

A clinical microbiology laboratory is validating a new point-of-care test for the rapid detection of influenza A and B viruses. To accurately determine the clinical sensitivity of the test, it should be compared to a gold standard method using:

Histopathological examination of lung tissue from an immunocompromised patient reveals large (8-15 ), spherical yeast cells with thick, refractile walls and characteristic single, broad-based budding. These findings are most suggestive of infection with:

Staphylococcus epidermidis, a common cause of healthcare-associated infections, forms biofilms on medical devices. The production of polysaccharide intercellular adhesin (PIA) is a key factor in biofilm maturation. The expression of PIA is primarily regulated by:

A researcher is studying the genetic relatedness of different isolates of Mycobacterium tuberculosis.

Which of the following molecular typing methods provides the highest discriminatory power for distinguishing between closely related strains?

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:

The human virome, the collection of viruses that reside in and on the human body, is increasinglyrecognized for its role in health and disease.

Which of the following statements regarding the human virome is MOST accurate?

A patient with a history of neutropenia develops a severe sinus infection. Tissue biopsy reveals broad, ribbon-like, non-septate hyphae with right-angle branching. The MOST likely causative organism belongs to the order:

A clinical microbiology laboratory is using isothermal nucleic acid amplification techniques for rapid detection of Mycobacterium tuberculosis in sputum. Compared to conventional PCR, isothermal methods offer the advantage of:

A research team is investigating the development of a novel vaccine against influenza virus. They are focusing on conserved epitopes within the hemagglutinin (HA) and neuraminidase (NA) proteins to elicit broadly neutralizing antibodies.

Which of the following approaches is MOST likely to achieve this goal?

During the investigation of a foodborne illness outbreak linked to raw sprouts, several bacterial isolates are obtained from patient stool samples and the implicated food source.

Which of the following molecular methods would be MOST useful for establishing a definitive link between the clinical isolates and the food isolate?

A traveler returning from sub-Saharan Africa presents with cyclical fevers, chills, and sweats. A Giemsa-
stained peripheral blood smear reveals multiple ring forms within red blood cells, some appliqué forms, and occasional banana-shaped gametocytes. No Schüffner's dots or red blood cell enlargement is observed.

Which Plasmodium species is the most likely cause?

A 55-year-old male with a history of poorly controlled diabetes mellitus develops a necrotizing fasciitis of his left lower extremity following a minor abrasion sustained while gardening. Initialcultures of the wound reveal a polymicrobial flora, including Gram-positive cocci in chains and Gram-negative bacilli. Over the next 48 hours, despite broad-spectrum antibiotic therapy, the patient's condition deteriorates, and new bullae with hemorrhagic fluid appear. Gram stain of this fluid now predominantly shows large, Gram-positive bacilli with subterminal spores.

Which of the following virulence factors is MOST likely contributing to the rapid tissue destruction observed in this patient?

The erm gene in Staphylococcus aureus confers resistance to which class(es) of antibiotics via modification of the ribosomal target site?