Micro BOC
The MOST sensitive substrate for the detection of beta-lactamases is: A. penicillin B. ampicillin C. cefoxitin D. nitrocefin
D. nitrocefin
An Enterococcus isolated from multiple blood cultures in a patient endocarditis should be: A. screened for high level amino glycoside resistance B. checked for tolerance C. assayed for serum antimicrobial activity D. tested for beta-lactamase production
A. screened for high level amino glycoside resistance
When Processing throat swabs for a group A Streptococcus culture, the medium of choice is: A. sheep blood agar B. rabbit blood agar C. human blood agar D. horse blood agar
A. sheep blood agar
Streptococcus pneumonia can be differentiated best from the viridans group of streptococci by: A. Gram stain B. the type of hemolysis C. colonial morphology D. bile solubility
D. bile solubility
A penicillin-resistant Neisseria gonorrhoeae produces: A. alpha-hemolysin B. beta-lactamase C. enterotoxin D. coagulase
B. beta-lactamase
The best medium for culture of Francisella tularensis is: A. Bordet-Gengou medium B. cystine glucose blood agar C. Loeffler medium D. charcoal selective media
B. cystine glucose blood agar
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
B. decreased
The expected colony count in a suprapubic urine from a healthy individual is: A. 0 CFU/mL B. 100 CFU/mL C. 1,000 CFU/mL D. 100,000 CFU/mL
A. 0 CFU/mL
A diabetic foot swab from a 82-year-old woman with recurrent infections is submitted for culture. The Gram stain reveals: -many neutrophils, no squamous dpi cells -many GNB -many GPC in chains The physicians requests that all pathogens would be worked up. In addition to the sheep blood and Mac plates routinely used for wound cultures, the tech might also process a(n): A. CNA B. Chocolate agar plate C. XLD D. chopped meat glucose
A. CNA
Which of the following must be incubated in a microaerophilic environment for optimal recovery of the organism? A. Campylobacter jejuni B. Escherichia coli C. Pseudomonas aeruginosa D. Proteus mirabilis
A. Campylobacter jejuni
Which selective medium is used for the isolation of gram-positive microorganisms? A. Columbia CNA with 5% sheep blood B. trypticase soy agar with 5% sheep blood C. eosin methylene blue D. modified Thayer-Martin
A. Columbia CNA with 5% sheep blood
The best medium for culture of Bordetella pertussis is: A. Regan-Lowe agar B. cystine blood agar C. Martin Lewis agar D. Ashdown agar
A. Regan-Lowe agar
Which of the following media can be used to culture Campylobacter jejuni? A. Skirrow medium B. CIN agar C. anaerobic CNA agar D. bismuth sulfate
A. Skirrow medium
GPC in chains are seen on a Gram stain from blood culture. This organism grows as a beta-hemolytic colony. Further tests that could be performed include: A. bile esculin, PYR, bacitracin and hippurate B. catalase and coagulase C. oxidase and deoxyribonuclease D. Vosges-Proskauer and methyl red
A. bile esculin, PYR, bacitracin and hippurate
Gram stain examination from a blood culture bottle shows dark blue, spherical organisms in clusters. Growth on sheep blood agar shows small, round, pale yellow colonies. Further tests should include: A. catalase production and coagulase test B. bacitracin susceptibility and serological typing C. oxidase and deoxyribosenuclease reactions D. Voges-Proskauer and methyl red reactions
A. catalase production and coagulase test
Which type of microscope would be MOST useful in examining viruses and the structure of microbial cells? A. electron B. phase-contrast C. dark-field D. bright-field
A. electron
Which of the follow is the MOST appropriate specimen source and primary media battery? A. endocervical: chocolate, Martin Lewis B. sputum: sheep blood, Thayer-Martin, KV-laked blood C.CSF: CNA, Mac D. urine: sheep blood, chocolate, CNA
A. endocervical: chocolate, Martin Lewis
A beta-hemolytic streptococcus that has been isolated from an ear culture grows up to the edge of a 0.04 unit bacitracin disk. Which of the following tests would help to determine if the organism is Enterococcus? A. growth in 6.5% in NaCl broth B. growth in the presence of penicillin C. optochin susceptibility D. fermentation of 10% lactose
A. growth in 6.5% in NaCl broth
In order to isolate Campylobacter coli/jejuni, the fecal specimen should be: A. inoculated onto selective plating media and incubated in reduced oxygen with aded CO2 at 42ºC B. sotred in tryptic soy broth before plating to ensure growth of the organism C. inoculated onto selected plating media and incubated at both 35ºC and at room temperature D. incubated at 35ºC for 2 hours in Cary-Blair media before inoculating onto selective plating media
A. inoculated onto selective plating media and incubated in reduced oxygen with aded CO2 at 42ºC
Group B, beta-hemolytic streptococci may be distinguished from other hemolytic streptococci by which of the following procedures? A. latex antigen type B. growth in 6.5% NaCl broth C. growth on bile esculin medium D. bacitracin susceptibility
A. latex antigen type
The lowest concentration of antibiotic that inhibits growth of a test organism is the: A. minimum inhibitory concentration B. serum inhibitory concentration C. minimum bactericidal titer D. maximum inhibitory titer
A. minimum inhibitory concentration
After 24 hours a blood culture from a newborn grows catalase-negative, GPC. The bacterial colonies are small, translucent and beta-hemolytic on a blood agar plate. Biochemical test results of a pure culture are: -bacitracin: resistant -CAMP reaction: + -bile esculin: not hydrolyzed -6.5% NaCl broth: no growth Assuming that all controls react properly and reactions are verified, the next step would be to: A. perform a Streptococcus group typing B. report the organism as Streptococcus pneumonia C. report the organism as Staphylococcus aureus D. Report the organism as Staphylococcus epidermidis
A. perform a Streptococcus group typing
The ONPG test allows organisms to be classified as a lactose fermenter by testing for which of the following? A. permease B. beta-galactosidase C. beta-lactamase D. phosphatase
B. beta-galactosidase
The susceptibility results below are reported on an Enterococcus faecalis isolated from peritoneal fluid. -ampicillin: sus. -vancomycin: res. -clindamycin: sus. -levofloxacin: res. -linezolid: sus. The physician calls questioning the results. Which of the following should have been done before the report was released? A. the clindamycin result should have been removed from the report since it is inactive against Enterococcus B. the ampicillin results should have been changed to res. since the isolate is vancomycin res. C. the linezolid result should have been removed from the report since it is inactive against Enterococcus D. ciprofloxacin should have been added to the report since levofloxacin was res.
A. the clindamycin result should have been removed from the report since it is inactive against Enterococcus
Upon review of a sputum Gram stain, the tech notes that the nuclei of all of the neutrophils present in the smear are staining dark blue. The best explanation for this finding is: A. the slide was inadequately decolorized with acetone/alcohol B.the sputum smear was prepared too thin C. the cellular components have stained as expected D. the iodine was omitted from the staining procedure
A. the slide was inadequately decolorized with acetone/alcohol
The steam autoclave method of sterilization: A. uses 15 lbs. of pressure for 15 minutes B. utilizes dry heat for 20 minutes C. produces a maximum temperatures of 100ºC D. requires a source of ethylene oxide
A. uses 15 lbs. of pressure for 15 minutes
A reliable test for distinguishing Staphylococcus aureus from other staphylococci is: A. oxidase B. coagulase C. catalase D. optochin susceptibility
B. coagulase
An antibiotic used to suppress or kill contaminating fungi in media is: A. penicillin B. cycloheximide C. streptomycin D. amphotericin B
B. cycloheximide
Which of the following clean catch urine culture colony counts indicates the patient likely has a urinary tract infection? A. 10^1 CFU/mL B. 10^3 CFU/mL C. 10^5 CFU/mL D. no growth
B. 10^3 CFU/mL
A vaginal/rectal swab is collected from a pregnant patient to screen for group B Streptococcus colonization. What is the best medium to use for specimen inoculation? A. blood agar B. LIM broth C. CNA agar D. thioglycollate broth
B. LIM broth
A 24 year-old man presents with pain on urination and urethral discharge. A Gram stain of the discharge is seen in the image: What is the MOST likely identification of this organism? A. Acinetobacter baumannii B. Neisseria gonorrohoeae C. Haemophilus ducreyi D. Escherichia coli
B. Neisseria gonorrohoeae
Production of beta-lactamase is inducible in which of the following? A. Haemophilus influenzae B. Staphylococcus aureus C. Cornebacterium diptheriae D. Streptococcus pyogenes
B. Staphylococcus aureus
Children who have infections with beta-hemolytic Streptococci can develop: A. acute pyelonephritis B. acute glomerulonephritis C. chronic glomerulonephritis D. nephrosis
B. acute glomerulonephritis
A D test is perfromed 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: res.; clindamycin: res. B. erythromycin: res.; clindamycin: sus. C. erythromycin: sus; clindamycin: res. D. erytrhomycin: sus; clindamycin: sus.
B. erythromycin: res.; clindamycin: sus.
After satisfactory performance of daily disk diffusion susceptibility quality control is documented, the frequency of quality control can be reduced to: A. twice a week B. every week C. every other week D. every month
B. every week
A liquid fecal specimen from a three-month-old infant is submitted for microbiological examination. In addition to culture on routine media for Salmonella & Shigella, this specimen should be routinely: A. examined for the presence of Entamoeba hartmanni B. examined for the presence of "Campylobacter" sp C. screened for the detection of enterotoxigenic Escherichia coli D. placed in thioglycollate broth to detect Clostridium botulinum
B. examined for the presence of Campylobacter sp
Which 2 diseases are usually preceded by infection with beta-hemolytic streptococci? A. rheumatic fever, undulant fever B. glomerulonephritis, rheumatic fever C. rheumatic fever, tularemia D. glomerulonephritis, undulant fever
B. glomerulonephritis, rheumatic fever
A beta-hemolytic streptococci that is bacitracin-sensitive and CAMP-negative is: A. group B B. group A C. beta-hemolytic, not group A, B, or D D. beta-hemolytic, group D|
B. group A
A urine Gram stain how's GPC in clusters. The organism tested catalase positive. To SPECIATE this organism from culture, the tech should perform a coagulase test and a/an: A. polymyxin B susceptibility B. novobiocin susceptibility C. oxidase D. beta-lactamase
B. novobiocin susceptibility
A 73-year-old man diagnosed as having pneumococcal meningitis is not responding to his penicillin therapy. Which of the following test should be performed on the isolate to best determine this organism's susceptibility to penicillin? A. beta-lactamase B. oxacillin disk diffusion C. penicillin disk diffusion D. Schlichter test
B. oxacillin disk diffusion
An antibiotic that inhibits cell wall synthesis is: A. chloramphenicol B. penicillin C. sulfamethoxazole D. colistin
B. penicillin
A 21-year-old patient presents with pharyngitis. A throat swab is collected and submitted for anaerobic culture. This specimen should be: A. set up immediately B. rejected as unacceptable C. inoculated into thioglycollate broth D. sent to a reference lab
B. rejected as unacceptable
Characteristically, enterococci are: A. unable to grow in 6.5% NaCl B. relatively resistant to penicillin C. sodium hippurate positive D. bile esculin negative
B. relatively resistant to penicillin
Three sets of blood cultures were obtained from an adult patient with fever and suspected endocarditis. The aerobic bottle of one set had growth of Staphylococcus epidermidis at 5 days of incubation. This indicates that: A. there was low-grade bacteremia B. the organism is MOST likely a contaminant C. the patient has a line infection D. the blood culture bottles are defective
B. the organism is MOST likely a contaminant
Which of the following is the MOST important variable in the recovery of organisms in patients with bacteremia? A. subculture of all bottles at day 5 of incubation B. the volume of blood cultured C. use of chlorhexadine for skin antisepsis D. collection of multiple blood culture sets from a single venipuncture
B. the volume of blood cultured
Which of the following factors would make an organism appear to be more resistant on a disk diffusion susceptibility test? A. too little agar in the plate B. too many organisms in the inoculum C. the presence of 0.5% NaCl in the medium D. a medium with a pH of 7.4
B. too many organisms in the inoculum
When performing the Kovac indole test, the substrate must contain: A. indole B. tryptophan C. ornithine D. paradimethylaminobenzaldehyde
B. tryptophan
When performing a stool culture, a colony type typical of an enteric pathogen is subcultured on a blood agar plate. the resulting pure culture is screened with several test to obtain the following results: -TSI: acid butt, alkaline slant, no gas, no H2S -phenylalanine deaminase: = -motility: + -serological testing: Shigella flexneri (Shigella subgroup B) The serological typing is verified with new kit and controls. The best course of action would be to: A. report the organism as Shigella flexneri without further testing B. verify reactivity of motility medium with + and = controls C. verify reactivity of the TSI slants with + and = controls for H2S production D. verify reactivity of phenylalanine deaminase with + and - controls
B. verify reactivity of motility medium with + and = controls
The Gram stain from a blood culture shows GPC in chains. No growth occurs on blood agar plates incubated both arrobically and anaerobically. Additional testing should be done to detect the presence of: A. Staphylococcus saprophytic us B. Aerococcus urinate C. Abitrophia defectiva D. Streptococcus pneumoniae
C. Abitrophia defectiva
The optochin (ethylhydrocupreine hydrochloride) disk is used for the identification of: A. Haemophilus influenzae B. group A beta-hemolytic streptococci C. Streptococcus pneumoniae D. alpha-hemolytic streptococci
C. Streptococcus pneumoniae
Which one of the following organisms does not require susceptibility testing to the antimicrobial indicated when isolated from a clinically significant source? A. Staphylococcus aureus-clindamycin B. Proteus mirabilis- gentamicin C. Streptococcus pyogenes- penicillin D. Escherichia coli- levofloxacin
C. Streptococcus pyogenes- penicillin
The optimal would specimen for culture of anaerobic organisms should be: A. a swab of a lesion obtained before administration of antibiotics B. a swab of a lesion obtained after administration of antibiotics C. a syringe filled with pus, obtained before administration of antibiotics D. a syringe filled with pus, obtained after administration of antibiotics
C. a syringe filled with pus, obtained before administration of antibiotics
In a quality control on a new batch of Mueller-Hinton plates using a stock culture of Staphylococcus aureus (ATCC 25923), all the disk zone sizes are too small. The MOST likely reason for this is that the: A. Mueller-Hinton plates were poured too thin B. potency of the antibiotic disks is too high C. bacterial suspension was not diluted to the proper concentration D. disks should have been set up on mannitol salt
C. bacterial suspension was not diluted to the proper concentration
In the Kirby-Bauer disc diffusion susceptibility test, which variable is critical when testing Pseudomonas species for antibiotic susceptibility to amino glycosides? A. incubation temperature B. duration of incubation C. cation content of media D. depth of agar
C. cation content of media
The enterotoxin produced by certain strains of hemolytic, coagulase positive Staphylococcus aureus: A. Is destroyed by boiling for 15-30 minutes B. is identical to the dermonecrotic toxin C. causes one type of bacterial food poisoning D. is highly antigenic
C. causes one type of bacterial food poisoning
Which of the following combinations is useful for confirming the presence of extended spectrum beta-lactamase in E. coli? A. ampicillin + cefepime B. cefoxitin + penicillin C. ceftazidime + clavulanic acid D. cefpodoxime + cefotaxime
C. ceftazidime + clavulanic acid
First-generation cephalosporins can be adequately represented by: A. cefotetan B. ceftriaxone C. cephalothin D. cefoxitin
C. cephalothin
Media used to support growth of Legionella pneumophila should contain which of the following additives? A. X and V factors B. hemin and Vitamin K C. charcoal and yeast extract D. dextrose and laked blood
C. charcoal and yeast extract
A 10 year-old child with cystic fibrosis presents with cough and shortness of breath. Her sputum Gram stain is seen in the image: Based on the Gram stain what would be the best medium and incubation condition to optimize recovery of the organism seen? A. Mac incubated in CO2 B. Tinsdale agar incubated in ambient air C. chocolate agar incubated in CO2 D. CNA incubated in ambient air
C. chocolate agar incubated in CO2
CSF from a febrile 25-year-old man with possible meningitis is rushed to the lab for a stat Gram stain and culture. While performing the Gram stain, the tech accidentally spills MOST of the specimen. The smear shows many neutrophils and no microorganisms. Since there is only enough CSF to inoculate one plate, the tech should use a: A. blood agar plate B. chopped meat glucose C. chocolate agar plate D. Thayer-Martin plate
C. chocolate agar plate
A medium that aids in the presumptive identification of organisms based on their appearances on the medium is called: A. enriched B. selective C. differential D. specialized
C. differential
A beta-hemolytic Streptococcus that is bacitracin-resistant and CAMP-positive is: A. group A or B B. group A C. group B D. beta-hemolytic, group D
C. group B
The organism MOST commonly associated with neonatal purulent meningitis is: A. Neisseria meningitidis B. Streptococcus C. group B streptococci D. Haemophilus influenzae
C. group B streptococci
A gamma-hemolytic Streptococcus that blackens bile esculin agar but does not grow in 6.5% NaCl broth is MOST likely: A. group B Streptococcus B. enterococcus C. group D Streptococcus D. streptococcus pneumoniae
C. group D Streptococcus
A catheterized urine is inoculated ontoa blood and Mac auger using 0.01 mL loop. After 48 hours, 68 colonies a small translucent nonhemolytic or organism grew on a blood agar but not Mac. Testing reveals small GP, catalase-negative cocci. The preliminary report and follow-up testing would be: A. growth of 680 colonies/mL of GPC, optochin and bacitracin susceptibility test to follow B. growth of 6800 colonies/ mL of a Staphylococcus species, coagulase test to follow C. growth of 6800 colonies/mL of a Streptococcus species, esculin hydrolysis and NaCl growth test to follow D. growth of 6800 colonies/mL of a Streptococcus species, no further testing
C. growth of 6800 colonies/mL of a Streptococcus species, esculin hydrolysis and NaCl growth test to follow
Which of the following groups of specimens would be acceptable for anaerobic culture? A. vaginal, eye B. ear, leg tissue C. pleural fluid, brain abscess D. urine, sputum
C. pleural fluid, brain abscess
In the optochin susceptibility test, if there is a zone of inhibition of 19-30 mm surrounding the disk following overnight incubation at 37°C, the colony MOST likely consists of: A. staphylococci B. streptococci C. pneumococci D. intestinal bacilli
C. pneumococci
A tech is reading a Gram stain from a CSF and observes many neutrophils and lancet-shaped GPDC. Which set of chemistry and hematology CSF results would MOST likely be seen in someone with this type of infection? A. result A B. result B C. result C D. result D
C. result C
Tests for beta-lactamase production in Haemophilus influenzae: 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
C. should be performed on all blood and CSF isolates
Susceptibility testing performed on quality control organisms using a new media lot number yielded zone sizes that were too large for all antibiotics tested. The testing was repeated using media from a perviously used lot number, and all zones sizes were acceptable. Which of the following best explains the unacceptable zone sizes? A. the antibiotic disks were not stored with the proper desiccant B. the depth of the media was too thick C. the depth of the media was too thin D. the antibiotic disks were not properly applied to the media
C. the depth of the media was too thin
The ability to detect oxacillin-resistant Staphyloccous aureus may be enhanced by: A. shortening incubation of standard susceptibility plates B. incubating susceptibility plates at 39º-41ºC C. using Mueller-Hinton broth with 2% NaCl D. adjusting inoculum to 0.1 McFarland before inoculating susceptibility plates
C. using Mueller-Hinton broth with 2% NaCl
In a disk diffusion susceptibility test, which of the following can result if disks are placed on the inoculated media and left at room temp. for an hour before incubation? A. the antibiotic would not diffuse into the medium, resulting in no zone B. zones of smaller diameter would result C. zones of larger diameter would result D. there would be no effect on the final zone diameter
C. zones of larger diameter would result
Which of the following is the MOST appropriate organism and media combination? A. Legionella sp.- Regan Lowe B. Clostridium difficile- phenlethyl alcohol (PEA) C. Campylobacter sp.- charcoal yeast extract D. Yersinia enterocolitica- cefsulodin-irgasan-novobiocin (CIN)
D. Yersinia enterocolitica- cefsulodin-irgasan-novobiocin (CIN)
Viridans streptococci can be differentiated from Streptococcus pneumoniae by: A. aplha hemolysis B. morphology C. catalase reaction D. bike solubility
D. bike solubility
A sheep blood agar plate inoculated with 0.001 mL of urine grows 70 colonies of "Staphylococcus aureus". How many colony forming units per mL of urine should be reported? A. 70 B. 700 C. 7,000 D. 70,000
D. 70,000
Refer to the following illustration: Examine the broth microdilution susceptibility test show above and determine the MIC for gentamicin. A. >64 µg/mL B. 32 µg/mL C. 16 µg/mL D. <2 µg/mL
D. <2 µg/mL
A Gram stain from a swab of a hand wound reveals: -mod. neutrophils -no squamous dpi cells -mod. GPC in chains -mod. large GNB Select the appropriate media that will selectively isolate each organism. A. KV-laked agar, Thayer-Martin B. sheep blood, Mac C. CNA, chocolate D. CNA, Mac
D. CNA, Mac
The image depicts a Gram stain (final magnification 1,000x) of a knee fluid from a patient who has recently undergone knee replacement surgery: The best interpretation of this Gram stain is: A. GPC suggestive of Staphylococcus B. GPB suggestive of Corynebacterium C. GPB suggestive of Listeria D. GPC suggestive of Streptococcus
D. GPC suggestive of Streptococcus
Which of the following organisms may be mistaken for Neisseria gonorrhoeae in Gram stained smears of uterine cervix exudates? A. Lactobacillus sp. B. Streptococcus agalactiae C. Pseudomonas aeruginosa D. Moraxella osloensis
D. Moraxella osloensis
Of the following bacteria, the MOST frequent cause of prosthetic heart valve infections occurring with 2-3 months after surgery is: A. Streptococcus pneumoniae B. Streptococcus pyogenes C. Staphylococcus aureus D. Staphylococcus epidermidis
D. Staphylococcus epidermidis
A gram-positive coccus isolated from a blood culture has the following characteristics: - optochin susceptibility: = - bacitracin (0.04 U) susceptibility: = - bile esculin hydrolysis: = - hippurate hydrolysis: + - catalase: = This organism MOST likely: A. Streptococcus aureus B. Streptococcus pneumoniae C. Streptococcus pyogenes D. Streptococcus agalactiae
D. Streptococcus agalactiae
An important cause of acute exudative pharyngitis is: A. Staphylococcus aureus (beta-hemolytic) B. Streptococcus pneumoniae C. Streptococcus agalactiae D. Streptococcus pyogenes|
D. Streptococcus pyogenes
A sputum specimen is received for culture and Gram stain. The Gram stained smear from this specimen is seen in the image (total magnification 100x): The tech's best course of action would be to: A. inoculate appropriate media and incubate anaerobically B. inoculate appropriate media and incubate aerobically C. call the physician and notify him of this "life-threatening" situation D. call the patient care area and request new specimen
D. call the patient care area and request new specimen
The MOST common cause for failure of a GasPak™ anaerobic jar to establish an adequate environment for anaerobic incubation is: A. the failure of the oxidation-reduction potential indicator system due to deterioration of methylene blue B. the failure of the packet to generate adequate H2 and/or CO2 C. condensation of water on the inner surface of the jar D. catalysts that have become inactivated after repeated use
D. catalysts that have become inactivated after repeated use
Proper media for culture of a urethral discharge from a man include: A. sheep blood & phenylethyl alcohol agars B. eosin-methylene blue & sheep blood agars C. thioglycollate broth & chocolate agars D. chocolate & modified Thayer-Martin agars
D. chocolate & modified Thayer-Martin agars
Which of the following methods is inadequate for the detection of vancomycin-intermediate S aureus? A. broth macrodilution B. agar dilution C. gradient diffusion D. disk diffusion
D. disk diffusion
A beta-hemolytic catalase-positive, gram-positive coccus is coagulase negative on the slide coagulase test. Which of the following is the MOST appropriate action in identification of this organism? A. report a coagulase-negative Staphylococcus B. report a coagulase-negative Staphylococcus aureus C. reconfirm the hemolytic reaction on a fresh 24-hour culture D. do a tube coagulase test to confirm the slide test
D. do a tube coagulase test to confirm the slide test
It is important to differentiate between Enterococcus and group D streptococci because: A. viridans streptococci are often confused with enterococci B. several enterococci cause severe puerperal sepsis C. group D streptococci are avirulent D. enterococci often show more antibiotic resistant and group D streptococci
D. enterococci often show more antibiotic resistant and group D streptococci
An aspirate of a deep wound was plated on blood agar plates and incubated aerobically and anaerobically. At 24 hours there was growth on both plates. This indicates that the organism is a(n): A. nonfermenter B. obligate anaerobe C. aerobe D. facultative anaerobe
D. facultative anaerobe
Which of the following antibiotics would routinely be tested and reported for isolates of Pseudomonas aeruginosa? A. penicillin B. erythromycin C. clindamycin D. gentamicin
D. gentamicin
"Nutritionally deficient" streptococci are: A. enterococci B. group D nonenterococci C. cell wall- deficient streptococci D. in the genera Granulicatella and Abiotrophia
D. in the genera Granulicatella and Abiotrophia
To quality control the autoclave, a vial of Bacillus stearothermophilus is autoclave and should then be: A. inoculated to blood agar B. incubated at 37°C C. inoculated to chocolate agar D. incubated at 56°C
D. incubated at 56°C
Which one of the following combinations of organisms would be appropriate as controls to test the functions listed? A. beta-hemolysis-negative Escherichia coli and Streptococcus pyrogens B. catalase-negative Staphylococcus aureus and Staphylococcus epidermidis C. H2S production-negative Proteus mirabilis and Staphylococcus epidermidis D. indole-negative Escherichia cole and Proteus mirabilis
D. indole-negative Escherichia cole and Proteus mirabilis
Which of the following antimicrobials would be inappropriate to report on an E.coli isolated from a wound culture? A. gentamicin B. ampicillin C. cefazolin D. nitrofurantoin
D. nitrofurantoin
An expectorated sputum is sent to the laboratory for culture from a patient with respiratory distress. The Gram stain of the specimen shows many squamous epithelial cells (>25/lpf) and rare neutrophils. The microscopic appearance of the organisms present include: -mod. GPC in chains and diplococci -mod. GNDC -mod palisading GPB all in moderate amounts This Gram stains MOST indicative of: A. a pneumococcal pneumonia B. an anaerobic infection C. an "Haemophilus" pneumonia D. oropharyngeal flora
D. oropharyngeal flora
Susceptibility testing is performed on a Staphylococcus aureus isolate from a blood culture with the following results: -oxacillin: res -cefazolin: sus -clindamycin: sus -erythromycin: su |-trimethoprim/sulfamethoxazole: sus -vancomycin: sus What should the tech do next? A. ceftriaxone should be reported instead of cefazolin B. clindamycin should be tested for inducible resistance prior to reporting C. the T/S result should be removed since all S aureus are resistant D. the cefazolin results should be changed to resistant since the oxacillin result is resistant
D. the cefazolin results should be changed to resistant since the oxacillin result is resistant
Vibrio parahaemolyticus can be isolated best from feces on: A. eosin methylene blue (EMB) agar B. Hektoen enteric (HE) agar C. Salmonella Shigella (SS) agar D. thiosulfate citrate bile salt (TCBS) agar
D. thiosulfate citrate bile salt (TCBS) agar
Which one of the following specimen requests is acceptable? A. feces submitted for anaerobic culture B. Foley catheter tip submitted for aerobic culture C. rectal swab submitted for direct smear for gonococci D. urine for culture of acid-fast bacilli
D. urine for culture of acid-fast bacilli
The procedure that assures the MOST accurate detection of mecA-mediated oxacillin resistance in routine broth micro dilution susceptibility testing against S aureus is: A. addition of 4% NaCl B. incubation at 30ºC C. incubation for 48 hours D. use of cefoxitin for testing
D. use of cefoxitin for testing
When using a control strain of Staphylococcus aureus, the tech notices that the zone around the oxacillin disk is too small. Which of the follow is the MOST likely explanation? A. inoculation of the pates 10 minutes after preparing the inoculum B. incubation of the Mueller-Hinton plates at 35ºC C. use of a 0.25 McFarland standard to prepare inoculum D. use of outdated oxacillin disks
D. use of outdated oxacillin disks
