Get Ready with ABMM Exam Dumps (2025)
Realistic ABMM Dumps are Available for Instant Access
NEW QUESTION # 36
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. Listeria monocytogenes
- B. Enterococcus faecalis
- C. Streptococcus pneumoniae
- D. Streptococcus agalactiae
Answer: C
NEW QUESTION # 37
A patient with a history of solid organ transplantation develops a severe respiratory illness. Bronchoalveolar lavage fluid is positive for cytomegalovirus (CMV) DNA by PCR, and cytological examination reveals characteristic "owl's eye" inclusions in enlarged cells. The MOST appropriate management strategy for this patient would include:
- A. Initiation of broad-spectrum antibiotics to cover potential bacterial coinfections.
- B. Treatment with antiviral agents such as ganciclovir or valganciclovir.
- C. Administration of corticosteroids to reduce inflammation.
- D. Supportive care and monitoring for spontaneous resolution.
Answer: B
NEW QUESTION # 38
A microbiology laboratory receives a corneal scraping from a patient with keratitis. Microscopic examination with calcofluor white stain reveals the presence of septate hyphae and conidiophores with a foot cell and phialides. The MOST likely genus is:
- A. Aspergillus
- B. Rhizopus
- C. Candida
- D. Mucor
Answer: A
NEW QUESTION # 39
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:
- A. Staphylococcus aureus
- B. Bacillus cereus
- C. Vibrio cholerae
- D. Clostridium difficile
Answer: B
NEW QUESTION # 40
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:
- A. Electron microscopy of the samples.
- B. Whole-genome sequencing of viral RNA.
- C. Rapid antigen detection assay.
- D. Viral culture on a broad range of cell lines.
Answer: C
NEW QUESTION # 41
Under the Clinical Laboratory Improvement Amendments (CLIA), participation in an approved external Proficiency Testing (PT) program serves primarily to:
- A. Validate the performance characteristics (e.g., sensitivity, specificity) of newly implemented test methods.
- B. Provide an objective, ongoing assessment of the accuracy and reliability of the laboratory's testing compared to its peers.
- C. Determine the reference intervals (normal ranges) for quantitative assays performed by the laboratory.
- D. Fulfill requirements for laboratory accreditation by The Joint Commission only.
Answer: B
NEW QUESTION # 42
A patient with HIV infection and a CD4+ T-cell count below 50 cells/µL 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. Direct cytopathic effect of JC virus on neurons.
- B. Lytic infection of oligodendrocytes by JC virus, leading to demyelination.
- C. Opportunistic infection by JC virus due to impaired cell-mediated immunity.
- D. Inflammatory demyelination triggered by JC virus infection of astrocytes.
Answer: B
NEW QUESTION # 43
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:
- A. Moraxella catarrhalis
- B. Legionella pneumophila
- C. Bordetella pertussis
- D. Haemophilus influenzae
Answer: C
NEW QUESTION # 44
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. Vancomycin
- B. Azithromycin
- C. Ciprofloxacin
- D. Penicillin
Answer: B
NEW QUESTION # 45
Which of the following bacterial genera inherently possesses D-alanyl-D-lactate peptide subunits in its peptidoglycan precursors, conferring natural, high-level resistance to vancomycin?
- A. Enterococcus (e.g., E. gallinarum, E. casseliflavus carrying vanC)
- B. Leuconostoc
- C. Staphylococcus
- D. Streptococcus
Answer: B
NEW QUESTION # 46
A 30-year-old female who recently returned from a hiking trip in the northeastern United States presents to her physician with a two-week history of a slowly expanding, erythematous rash with central clearing on her thigh. She also reports intermittent fatigue, arthralgias, and mild headache. Serological testing reveals a positive IgM and IgG response to Borrelia burgdorferi. Which of the following mechanisms is MOST significant in the pathogenesis of the clinical manifestations observed in this patient?
- A. Production of potent exotoxins leading to direct tissue damage
- B. Evasion of phagocytosis through a thick polysaccharide capsule
- C. Intracellular replication within macrophages leading to disseminated infection
- D. Induction of a strong pro-inflammatory cytokine response by the host
Answer: D
NEW QUESTION # 47
A patient with severe combined immunodeficiency (SCID) develops a progressive respiratory illness.
Bronchoalveolar lavage fluid is examined using direct fluorescent antibody (DFA) staining, which reveals numerous cysts of Pneumocystis jirovecii. The cysts appear:
- A. Oval-shaped with a thin wall and internal nuclei.
- B. Small and round with a thick wall, containing sporozoites.
- C. Large and multinucleated with prominent endospores.
- D. Cup-shaped or helmet-shaped with internal structures.
Answer: D
NEW QUESTION # 48
A clinical microbiology laboratory is investigating an outbreak of vancomycin-resistantEnterococcus faecium (VRE) in a hospital. Whole-genome sequencing of isolates from different patients reveals the presence of the vanA operon on a mobile genetic element that is highly conserved across all isolates. This finding MOST strongly suggests:
- A. Independent acquisition of vancomycin resistance by different E. faecium strains.
- B. Selection of vancomycin-resistant mutants within a susceptible E. faecium population due to antibiotic pressure.
- C. Clonal spread of a single VRE strain carrying the vanA operon.
- D. Horizontal transfer of the vanA operon to multiple susceptible E. faecium strains.
Answer: C
NEW QUESTION # 49
A Klebsiella pneumoniae isolate from a bloodstream infection shows the following susceptibility profile:
Meropenem (MIC = 8 µg/mL, R), Imipenem (MIC = 16 µg/mL, R), Ertapenem (MIC = 4 µg/mL, R), Ceftazidime/avibactam (MIC = 1 µg/mL, S), Aztreonam (MIC = 32 µg/mL, R). Which resistance mechanism is most strongly suggested by this pattern?
- A. Metallo-beta-lactamase (MBL) production
- B. Extended-Spectrum Beta-Lactamase (ESBL) production alone
- C. Klebsiella pneumoniae Carbapenemase (KPC) production
- D. AmpC beta-lactamase hyperproduction coupled with porin loss
Answer: C
NEW QUESTION # 50
A patient with a history of travel to a rural area develops a febrile illness with myalgias and thrombocytopenia. Laboratory testing reveals the presence of morulae within circulating leukocytes. The MOST likely diagnosis is:
- A. Lyme disease
- B. Anaplasmosis
- C. Babesiosis
- D. Ehrlichiosis
Answer: D
NEW QUESTION # 51
According to the current CDC-recommended laboratory algorithm for diagnosing HIV infection in adults and children aged >18 months, what is the recommended initial screening test?
- A. HIV-1/HIV-2 antibody differentiation immunoassay
- B. HIV RNA nucleic acid test (NAT)
- C. HIV-1/HIV-2 antigen/antibody combination immunoassay
- D. HIV-1 p24 antigen assay only
Answer: C
NEW QUESTION # 52
A patient with a history of diabetes mellitus develops a severe foot ulcer. Deep tissue cultures grow multiple anaerobic bacteria, including Clostridium perfringens. The MOST concerning virulence factor produced by this organism in this context is:
- A. Tetanospasmin
- B. Alpha-toxin (lecithinase)
- C. Hyaluronidase
- D. Botulinum toxin
Answer: B
NEW QUESTION # 53
A Gram stain of cerebrospinal fluid (CSF) from a 2-year-old child with meningitis shows small, pleomorphic Gram-negative coccobacilli. Culture on chocolate agar yields growth, but there is no growth on standard 5% sheep blood agar unless streaked near a colony of Staphylococcus aureus. This phenomenon indicates a requirement for which growth factor(s)?
- A. Both Factor X and Factor V
- B. Cysteine and pyridoxal
- C. Factor X (hemin) only
- D. Factor V (NAD) only
Answer: D
NEW QUESTION # 54
Chagas disease, characterized by acute Romana's sign and potential chronic cardiac and gastrointestinal complications, is caused by which vector-borne protozoan parasite?
- A. Leishmania donovani
- B. Toxoplasma gondii
- C. Trypanosoma cruzi
- D. Trypanosoma brucei gambiense
Answer: C
NEW QUESTION # 55
A patient develops a febrile illness with jaundice and dark urine after receiving a blood transfusion.
Laboratory testing reveals an elevated level of unconjugated bilirubin and a positive direct Coombs test.
Serological testing is positive for antibodies against a protozoan parasite that infects erythrocytes. The MOST likely causative agent is:
- A. Toxoplasma gondii
- B. Trypanosoma cruzi
- C. Plasmodium falciparum
- D. Babesia microti
Answer: D
NEW QUESTION # 56
A clinical microbiology laboratory is monitoring the emergence of resistance to colistin in Gram-negative bacteria. Resistance to colistin is often mediated by modifications of the bacterial lipopolysaccharide (LPS).
The genetic basis for acquired colistin resistance most commonly involves:
- A. Mutations in genes encoding enzymes that modify the lipid A component of LPS.
- B. Acquisition of genes encoding efflux pumps that specifically target colistin.
- C. Alterations in the outer membrane porin proteins, reducing colistin uptake.
- D. Production of enzymes that directly inactivate the colistin molecule.
Answer: A
NEW QUESTION # 57
A clinical microbiology laboratory is implementing a new real-time PCR assay for the direct detection of Chlamydia trachomatis in urine samples. To ensure the accuracy of negative results, it is essential to include:
- A. A high concentration of the Chlamydia trachomatis target sequence.
- B. An internal amplification control to detect PCR inhibition.
- C. A melting curve analysis to confirm the specificity of the amplicon.
- D. A positive control containing Neisseria gonorrhoeae DNA.
Answer: B
NEW QUESTION # 58
An acid-fast bacillus isolate recovered from a respiratory specimen after 3 weeks of incubation on Löwenstein- Jensen medium is initially non-pigmented when grown in the dark. After exposure to light for several hours, the colonies develop a distinct yellow-orange pigment. This organism is classified as a:
- A. Nonchromogen
- B. Rapid grower
- C. Photochromogen
- D. Scotochromogen
Answer: C
NEW QUESTION # 59
Microscopic examination of a Calcofluor white stained sputum sample from an immunocompromised patient with suspected invasive pulmonary infection reveals septate hyphae that branch dichotomously at acute (approximately 45°) angles. Conidial structures are observed, showing conidiophores arising from a specialized foot cell, terminating in a flask-shaped vesicle that bears phialides only on the upper two-thirds (uniseriate arrangement). Chains of small, round conidia are produced. This morphology is most characteristic of:
- A. Aspergillus fumigatus
- B. Aspergillus flavus
- C. Rhizopus arrhizus
- D. Fusarium solani
Answer: A
NEW QUESTION # 60
......
Download Exam ABMM Practice Test Questions with 100% Verified Answers: https://www.exam4pdf.com/ABMM-dumps-torrent.html
Share Latest ABMMTest Practice Test Questions, Exam Dumps: https://drive.google.com/open?id=1_hJdstIbFLxIzXmQAZZjH-bnvxV_aVw1
