A nonfermenting organism that grows on MacConkey, is nonmotile, oxidase-negative, and has the characteristic coccobacilli Gram stain seen in the image is:, A. Pseudomonas aeruginosa, B. Stenotrophomonas maltophilia, C. Proteus mirabilis, D. Acinetobacter baumannii, All species of the genus Neisseria have the enzyme to oxidize:, A. Naphthylamine, B. Dimethylaminobenzaldehyde, C. Glucopyranoside, D. Tetramethyl-phenylenediamine, Which of the following is the most reliable test to differentiate Neisseria lactamica from Neisseria meningitidis?, A. Growth on a modified Thayer-Martin agar, B. Nitrite reduction to nitrogen gas, C. Rapid ONPG, D. Utilization of maltose, A method for the definitive identification of Neisseria gonorrhoeae is:, A. Degradation of amino acids, B. EIA, C. Utilization of carbohydrates, D. Resistance to penicillins and cephalosporins, Gram-negative diplococci that grow on modified Thayer-Martin medium can be further confirmed as Neisseria gonorrhoeae if they are:, A. Oxidase-positive, glucose-positive, and maltose-positive, B. Oxidase-positive and glucose-positive, maltose-negative, C. Oxidase-positive, maltose-positive, and glucose-negative, D. Glucose-positive, oxidase-negative and maltose-negative, 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?, A. Moraxella catarrhalis, B. Neisseria gonorrhoeae, C. Neisseria meningitidis, D. Vibrio cholerae, The left image shows the Gram stain of an organism growing on sheep blood agar, while the right image shows growth of this organism on Tinsdale agar. The most likely organism is:, A. Bacillus cereus, B. Corynebacterium diphtheriae, C. Listeria monocytogenes, D. Nocardia asteroides, The best test to differentiate Listeria monocytogenes from Corynebacterium species is:, A. Catalase, B. Motility at 25°C, C. Motility at 35°C, D. Gram stain, Which feature distinguishes Erysipelothrix rhusiopathiae from other clinically significant non-spore-forming, gram-positive, facultatively anaerobic bacilli?, A. "Tumbling" motility, B. Beta-hemolysis, C. More pronounced motility at 25°C than 37°C, D. H₂S production, Listeria can be confused with some Streptococcaceae because it is beta-hemolytic and:, A. Nonmotile, B. Catalase-negative, C. Oxidase-positive, D. Esculin positive, Which of the following gram-positive bacilli is associated with infections in neonates, pregnant women, elderly adults, and outbreaks of food contamination? Its growth on sheep blood agar is shown in the image., A. Clostridium perfringens, B. Corynebacterium jeikeium, C. Erysipelothrix rhusiopathiae, D. Listeria monocytogenes, Which of the following pairs of organisms usually grow on kanamycin, vancomycin, laked blood agar?, A. Bacteroides and Prevotella, B. Mobiluncus and Gardnerella, C. Porphyromonas and Enterococcus, D. Veillonella and Capnocytophaga, The reverse CAMP test, lecithinase production, double zone hemolysis, and Gram stain morphology are all useful criteria in the identification of:, A. Clostridium perfringens, B. Streptococcus agalactiae, C. Cutibacterium acnes, D. Bacillus anthracis, Which of the following sets of organisms may exhibit a brick red fluorescence?, A. Porphyromonas asaccharolytica and Clostridium ramosum, B. Clostridioides difficile and Fusobacterium species, C. Prevotella melaninogenica and Porphyromonas asaccharolytica, D. Fusobacterium species and Bacteroides fragilis, The presence of 20% bile in agar will allow growth of:, A. Fusobacterium necrophorum, B. Bacteroides fragilis, C. Prevotella melaninogenica, D. Porphyromonas asaccharolytica, Which testing platform meets this description? An isolated colony is irradiated by a laser, which ionizes the biomolecules and causes them to become accelerated in an electric field. The ionized biomolecules then enter a flight tube where they are separated by their mass-to-charge ratio., A. MALDI-TOF, B. Multiplex PCR, C. Pulsed-field gel electrophoresis, D. Sequencing, Which one of the following organisms could be used as the positive quality control test for lecithinase on egg yolk agar?, A. Bacteroides fragilis, B. Fusobacterium necrophorum, C. Clostridium perfringens, D. Clostridium sporogenes, Which of the 2 different antimicrobial agents listed below are commonly used and may result in synergistic action in the treatment of endocarditis caused by Enterococcus faecalis?, A. An aminoglycoside and a macrolide, B. A penicillin derivative and an aminoglycoside, C. A cell membrane active agent and nalidixic acid, D. A macrolide and a penicillin derivative, The lowest concentration of antibiotic that inhibits growth of a test organism is the:, A. Minimum bactericidal concentration, B. Minimum inhibitory concentration, C. Serum bactericidal concentration, D. Serum inhibitory concentration, Penicillin resistance in Neisseria gonorrhoeae can be due to the organism producing:, A. Beta-D-galactosidase, B. Beta-lactamase, C. Butyrate esterase, D. DNase, The most sensitive substrate for the detection of beta-lactamases is:, A. Penicillin, B. Ampicillin, C. Cefoxitin, D. Nitrocefin, An Enterococcus isolated from multiple blood cultures in a patient endocarditis should be:, A. Screened for high level aminoglycoside resistance, B. Checked for tolerance, C. Assayed for serum antimicrobial activity, D. Tested for beta-lactamase production, The procedure that assures the most accurate detection of mecA-mediated oxacillin resistance in routine broth microdilution susceptibility testing against S. aureus is:, A. Addition of 4% NaCl, B. Incubation at 30°C, C. Incubation for 48 hours, D. Testing with cefoxitin, Susceptibility testing performed on quality control organisms using a new media lot number yields zone sizes that are too large for all antibiotics tested. The testing is repeated using media from a previously used lot number, and all zone sizes are acceptable. The unacceptable zone sizes are best explained by the:, A. Antibiotic disks are not stored with the proper desiccant, B. Depth of the media is too thick, C. Depth of the media is too thin, D. Antibiotic disks are not properly applied to the media, In disk diffusion susceptibility testing, as an antimicrobial agent diffuses away from the disk, the concentration of antibiotic is:, A. Increased, B. Decreased, C. Unchanged, D. Inoculum dependent, When performing a disk diffusion susceptibility test, the antibiotic disks are placed on the agar 30 minutes after organism inoculation and then incubated within 15 minutes of the disk placement. This departure from the recommended procedure will result in:, A. The antibiotic not diffusing into the medium, resulting in no zone, B. Decreased zone diameters, C. Increased zone diameters, D. No effect on the final zone diameter, An Enterobacterales organism will appear to be more resistant on a disk diffusion susceptibility test if the:, Depth of the agar is too thin, B. Inoculum is too concentrated, C. The antimicrobial agent in disk is too concentrated, D. Test interpretation occurs after 12 hours of ambient air incubation, When performing antimicrobial susceptibility testing on Enterobacterales, first-generation cephalosporins can be adequately represented by:, A. Cefuroxime, B. Ceftriaxone, C. Cefazolin, D. Cefonicid, An antibiotic that inhibits cell wall synthesis is:, A. Chloramphenicol, B. Colistin, C. Penicillin, D. Sulfamethoxazole, Tests for Haemophilus influenzae beta-lactamase production:, A. Are not commercially available, B. Include tests that measure a change to an alkaline pH, C. Should be performed on all blood and CSF isolates, D. Are not valid for any other bacterial species, Interpret the gentamicin MIC shown in this broth microdilution susceptibility test:, A. >64 μg/mL, B. 32 μg/mL, C. 16 μg/mL, D. ≤2 μg/mL, When using a control strain of Staphylococcus aureus, the technologist notices that the zone around the cefoxitin disk is too small. Which of the following is the most likely explanation?, A. Inoculation of the plates 10 minutes after preparing the inoculum, B. Incubation of the Mueller-Hinton plates at 35°C, C. Use of a 0.25 McFarland standard to prepare inoculum, D. Use of outdated cefoxitin disks, In the disk diffusion method of determining antibiotic susceptibility, the size of the inhibition zone used to indicate susceptibility has been determined by:, A. Testing 30 strains of 1 genus of bacteria, B. Correlating the zone size with minimum inhibitory concentrations, C. Correlating the zone size with minimum bactericidal concentrations, D. Correlating the zone size with the antibiotic content of the disk, A D test is performed on an isolate of Staphylococcus aureus to determine inducible clindamycin resistance. Based on the result seen in the image how should the erythromycin and clindamycin be reported?, A. Erythromycin: resistant; clindamycin: resistant, B. Erythromycin: resistant; clindamycin: susceptible, C. Erythromycin: susceptible; clindamycin: resistant, D. Erythromycin: susceptible; clindamycin: susceptible, An antimicrobial combination that is useful for confirming the presence of extended spectrum beta-lactamases in E. coli is:, A. Ampicillin + cefepime, B. Cefoxitin + penicillin, C. Ceftazidime + clavulanic acid, D. Cefpodoxime + cefotaxime, Susceptibility testing is performed on a Staphylococcus aureus isolate from a blood culture: oxacillin: resistant; cefazolin: susceptible; clindamycin: susceptible; erythromycin: susceptible; trimethoprim/sulfamethoxazole: susceptible; vancomycin: susceptible. What should the technologist do next?, A. Ceftriaxone should be reported instead of cefazolin, B. Clindamycin should be tested for inducible resistance prior to reporting, C. The trimethoprim/sulfamethoxazole result should be removed since all S. aureus are resistant, D. The cefazolin result should be changed to resistant since the oxacillin result is resistant, A quality control procedure on a new batch of Mueller-Hinton agar plates using a Staphylococcus aureus ATCC strain and incubation in ambient air results in all the disk zone sizes measuring too small. The most likely reason is that the:, A. Mueller-Hinton plates are poured too thin, B. Potency of the antibiotic disks is too high, C. Bacterial suspension is not diluted to the proper concentration, D. Incubation should have been in a 5-10% CO₂ atmosphere, The antimicrobial susceptibility test for a Klebsiella pneumoniae isolated from a pleural fluid had the results: amikacin: susceptible; ampicillin: susceptible; cefazolin: susceptible; cefoxitin: susceptible; gentamicin: susceptible; tobramycin: susceptible. The next best step is to:, A. Report out the antimicrobial susceptibility results without further investigation, B. Verify the results as it is unusual for Klebsiella pneumoniae to be susceptible to ampicillin, C. Verify the results as it is unusual for Klebsiella pneumoniae to be susceptible to cefazolin, D. Verify the results as it is unusual for Klebsiella pneumoniae to be susceptible to both ampicillin and cefazolin, A Klebsiella pneumoniae isolate is known to produce carbapenemase; therefore, it therapeutically will not respond to the antibiotics:, A. Amoxicillin, cefazolin and imipenem, B. Colistin and rifampin, C. Sulfamethoxazole and trimethoprim-sulfamethoxazole, D. Tetracycline and doxycycline, Representative beta-lactam antibiotics and their mechanism of action include:, A. Ampicillin, cefazolin and imipenem; and inhibition of cell wall synthesis, B. Ampicillin, cefazolin and imipenem; and inhibition of DNA replication, C. Ciprofloxacin, levofloxacin and aztreonam; and inhibition of cell wall synthesis, D. Ciprofloxacin, levofloxacin and aztreonam; and inhibition of DNA replication, Haemophilus influenzae becomes resistant to ampicillin when the organism produces:, A. A capsule of polysaccharide material, B. NAD, C. Porphobilinogen, D. The beta-lactamase enzyme, Clinical resistance to penicillin correlates most frequently with beta-lactamase production in:, A. Chlamydia trachomatis, B. Neisseria gonorrhoeae, C. Neisseria meningitidis, D. Treponema pallidum, An antimicrobial susceptibility method recommended to detect vancomycin-intermediate Staphylococcus aureus is:, A. MIC broth dilution, B. Agar dilution, C. Kinetic diffusion, D. Disk diffusion, Examples of Category A agents of bioterrorism include:, A. Bacillus anthracis, MDR tuberculosis, B. Francisella tularensis, Yersinia pestis, C. Hantavirus, variola major virus, D. VRE, Bacillus cereus, BSL-3 organisms are those that:, A. Cause human disease but are not readily transmitted among hosts, B. Do not ordinarily cause human disease; they require minimal safety procedures, C. Have very high risk of serious disease and no available treatment or vaccine, D. Produce serious disease and are transmitted by respiratory route.

Micro Exit 3

by
Print
Embed

Leaderboard

Visual style

Options

Switch template

Continue editing: ?