SUMMATIVE EXAM #6

100問 • 1年前

問題一覧

Composition of Gower’s diluent: A. Acetic acid, sodium sulfate, water B. Citrate, formaldehyde C. Mercuric chloride, sodium sulfate, sodium chloride D. Sodium chloride, wate

A. Acetic acid, sodium sulfate, water

1:200 dilution of a patient’s sample was made and 336 red cells were counted in an area of 0.2 mm2 . What is the RBC count? A. 1.68 × 1012/L B. 3.36 × 1012/L C. 4.47 × 1012/L D. 6.66 × 1012/L

B. 3.36 × 1012/L

A manual WBC count is performed. Eighty WBCs are counted in the four large corner squares of a Neubauer hemacytometer. The dilution is 1:100. What is the total WBC count? A. 4.0 × 109/L B. 8.0 × 109/L C. 20.0 × 109/L D. 200.0 × 109/L

C. 20.0 × 109/L

A manual white blood cell (WBC) count was performed. A total of 36 cells were counted in all 9- mm2 squares of a Neubauer-ruled hemacytometer. A 1:10 dilution was used. What is the WBC count? A. 0.4 × 109/L B. 2.5 × 109/L C. 4.0 × 109/L D. 8.0 × 109/L

A. 0.4 × 109/L

An adult has a total white blood cell count of 4.0 X 109/L (4.0 X 103/µL). The differential count is as follows: polymorphonuclear neutrophils (PMNs) 25%, bands 5%, lymphocytes 65%, and monocytes 5%. The absolute value reference range for lymphocytes is 1.0 to 4.0 X 109/L. Which of the following is true? A. The percentage of lymphocytes is normal. B. There is an absolute lymphocytosis. C. There is a relative lymphocytosis. D. There is both an absolute and a relative lymphocytosis

C. There is a relative lymphocytosis.

A 19-year-old man came to the emergency department with severe joint pain, fatigue, cough, and fever. Review the following laboratory results: WBCs 21.0 × 109/L RBCs 3.23 × 1012/L Hgb 9.6 g/dL PLT 252 × 109/L Differential: § 17 band neutrophils § 75 segmented neutrophils § 5 lymphocytes § 2 monocytes § 1 eosinophil § 26 NRBCs What is the corrected WBC count? A. 8.1 × 109/L B. 16.7 × 109/L C. 21.0 × 109/L D. 80.8 × 109/L

B. 16.7 × 109/L

In the Sanford Method of OFT, normal RBCs demonstrate initial hemolysis at which tube? A. 14 B. 17 C. 20 D. 22

D. 22

In the Sanford Method of OFT, normal RBCs demonstrate complete hemolysis at which tube? A. 14 B. 17 C. 20 D. 22

B. 17

The reference value for mean platelet volume (MPV) is approximately: A. 2 to 4 fL B. 5 to 7 fL C. 8 to 10 fL D. 11 to 14 fL

C. 8 to 10 fL

A normal PDW is: A. Less than 5% B. Less than 10% C. Less than 15% D. Less than 20%

D. Less than 20%

In ELISA, which of the following can be attached to a solid-phase support (e.g. polystyrene)? A. Antigen and enzyme B. Antibody and albumin C. Antigen and antibody D. Antigen and albumin

C. Antigen and antibody

In EIA, antigen or antibody is typically bound to: A. Liquid phase B. Semi-solid phase C. Solid-phase D. Any of these

C. Solid-phase

In EIA, which of the following can be used qualitatively to determine the presence of an antigen or antibody or quantitatively to determine the actual concentration of an analyte in an unknown specimen? A. Antibody B. Antigen C. Enzyme label D. Solid-phase

C. Enzyme label

Indirect immunofluorescence is similar to which type of enzyme immunoassay in terms of the performance of the assay? A. Competitive EIA B. Capture EIA C. ELISA D. Homogenous assay

C. ELISA

For immunofluorescence, the tissue should be: A. Fixed in formalin B. Fixed in alcohol C. Fixed in b-5 D. Unfixed

D. Unfixed

Tissue for immunofluorescence must be: A. Fixed briefly in formalin and then frozen B. Frozen and then fixed in acetone C. Fixed in alcohol and paraffin processed D. Frozen and unfixed

D. Frozen and unfixed

Pre-analytical phase: A. Patient identification B. Patient identification, test order accuracy C. Test order accuracy, blood culture contamination D. Test order accuracy, patient identification, blood culture contamination

D. Test order accuracy, patient identification, blood culture contamination

Formula weight: A. Molarity B. Normality C. Atomic weight D. Molecular weight

D. Molecular weight

Serologic “to deliver” (TD) pipettes are identified by which of the following? A. Two etched bands near the top B. Self-draining capacity C. Dual-purpose pipette labels D. Blue graduation labels

A. Two etched bands near the top

A highly sensitive laboratory instrument which can accurately measure mass in the sub-milligram range to a high degree of precision: A. Analytical balance B. Triple beam balance C. Graduated cylinder D. Volumetric flask

A. Analytical balance

All sealed centrifuge buckets should be loaded and unloaded in a/an: A. Incubator B. Dry heat oven C. Fume hood D. Biological safety cabinet

D. Biological safety cabinet

Which monochromator specification is required in order to measure the true absorbance of a compound having a natural absorption bandwidth of 30 nm? !!! A. 50-nm bandpass B. 25-nm bandpass C. 15-nm bandpass D. 5-nm bandpass

D. 5-nm bandpass

Nephelometry measures the light scatter of: A. Ions B. Macromolecules complexes C. Antibodies D. Soluble antigens

B. Macromolecules complexes

Liebermann-Burchard test is used for chemical estimation of cholesterol. What is the function of acetic anhydride in the test? A. Reducing agent B. Alkalinizing agent C. Solvent and oxidizing agent D. Solvent and dehydrating agent

D. Solvent and dehydrating agent

Lipoprotein electrophoresis from origin to anode: !!!! A. HDL, LDL, VLDL, chylomicrons B. HDL, VLDL, LDL, chylomicrons C. Chylomicrons, LDL, VLDL, HDL D. Chylomicrons, VLDL, LDL, HDL

C. Chylomicrons, LDL, VLDL, HDL

True of hypernatremia: A. 135 mmol/L B. 140 mmol/L C. 145 mmol/L D. Vomiting

D. Vomiting

Which of the following enhances calcium resorption from bone and renal tubular reabsorption? !!! A. Parathyroid hormone B. Calcitonin C. Cortisol D. Aldosterone

A. Parathyroid hormone

Which of the following stimulates calcium uptake by bone and causes decreased renal tubular reabsorption? !!! A. Parathyroid hormone B. Calcitonin C. Cortisol D. Aldosterone

B. Calcitonin

Which of the following hormones involved in calcium regulation acts by decreasing both calcium and phosphorous? !!!! A. PTH B. Calcitonin C. Vitamin D D. Cortisol

B. Calcitonin

Of the following, which will MOST likely interfere with quantitation of thyroglobulin? A. Antithyroglobulin autoantibodies B. Thyroid-stimulating antibodies C. TSH receptor antibodies D. Thyroid peroxidase antibodies

A. Antithyroglobulin autoantibodies

Acute toxicity: A. Single exposure B. Short-term exposure C. Dose sufficient to cause immediate toxic effects D. All of these

D. All of these

All of the following refers to CHRONIC TOXICITY, EXCEPT: A. Dose is sufficient to cause immediate toxic effects B. Repeated frequent exposure C. Exposure for extended periods for greater than 3 months and possibly years D. Doses are insufficient to cause an immediate response

A. Dose is sufficient to cause immediate toxic effects

Carbon monoxide expresses its toxic effects by causing a ______ shift in the oxygen–hemoglobin dissociation curve, resulting in: !!! A. Right; increased amount of oxygen delivered to tissues B. Left; increased amount of oxygen delivered to tissues C. Right; decreased amount of oxygen delivered to tissues D. Left; decreased amount of oxygen delivered to tissues

D. Left; decreased amount of oxygen delivered to tissues

Which substance has the longest detection time? !!! A. Amphetamines B. Cocaine C. Benzodiazepines D. Marijuana

D. Marijuana

Classic approach to bacterial identification, and MOST IDENTIFICATION strategies are still based on bacterial: !!! A. Genotype B. Phenotype C. Both of these D. None of these

B. Phenotype

Function of IODINE in Gram staining: !!! A. Stains all bacteria purple B. Fixes crystal violet to cells C. Removes crystal violet from gram negative D. Stains gram negative pink

B. Fixes crystal violet to cells

Addition of egg yolk to nutritive media: !! A. Basal medium B. Enriched medium C. Enrichment medium D. Selective medium

B. Enriched medium

All of the following are differential media except: !!! A. Blood agar B. Chocolate agar C. MacConkey’s agar D. Eosin methylene blue agar

B. Chocolate agar

Green or brown zone around the colonies: A. Alpha hemolysis B. Beta hemolysis C. Gamma hemolysis D. Alpha prime hemolysis

A. Alpha hemolysis

Colonies that are irregular in shape and/or have irregular margins are likely to be _____ organisms: A. Aerobe B. Anaerobe C. Motile D. Glucose fermenter

C. Motile

Spreading growth on semisolid medium: !!! A. Fermenter B. Nonfermenter C. Motile D. Nonmotile

C. Motile

Transport media: !! A. Preserve the viability of microorganisms in the specimen B. Allow multiplication C. Prevent specimen from drying D. All of these

A. Preserve the viability of microorganisms in the specimen

Components of transport media, EXCEPT: !!! A. Buffers B. Peptones C. Salts D. Nitrogen

D. Nitrogen

Iodophor: !! A. Iodine and alcohol B. Iodine and detergent C. Iodine and saline D. Iodine and water

B. Iodine and detergent

When cleansing the skin with alcohol and then iodine for the collection of a blood culture, the iodine (or iodophor) should remain intact on the skin for at least: !! A. 10 seconds B. 30 seconds C. 60 seconds D. 5 minutes

C. 60 seconds

Which of the following is a DISINFECTANT? !!!! MUST KNOW A. Benzalkonium chloride B. Chlorhexidine gluconate C. Household bleach D. Hydrogen peroxide

C. Household bleach

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

When setting up a urine culture, a calibrated loop is used that delivers a specific amount of urine to the media plate. What is that amount? A. 0.01 or 0.001 mL of urine B. 0.10 or 0.01 mL of urine C. 0.001 or 0.0001 mL of urine D. None of the above is correct

A. 0.01 or 0.001 mL of urine

Flocked swab: MUST KNOW !!! A. Flocked with cotton B. Flocked with gauze C. Flocked with cotton and gauze D. Flocked with nylon

D. Flocked with nylon

1000. Respiratory specimens are best collected with what type of swabs? MUST KNOW! A. Calcium alginate swabs B. Dacron or polyester-tipped swabs C. Swabs with cotton tips or wooden shafts D. All of the above are acceptable

B. Dacron or polyester-tipped swabs

CONTAINER for stool culture: MUST KNOW! A. Stuart's medium B. Amies medium C. Sterile, screw capped container D. Clean, leakproof containe

D. Clean, leakproof container

MUST KNOW! A liquid fecal specimen from a three-month-old infant is submitted for microbiological examination. In addition to culture on routine media for Salmonella and Shigella, this specimen should be routinely: A. Examined for the presence of Entamoeba hartmanni B. Examined for the presence of Camylobacter 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 Camylobacter sp

MUST KNOW! MIC is the concentration of the: A. First tube with growth B. Last tube with growth C. First tube with no growth D. Last tube with no growth

C. First tube with no growth

MUST KNOW !! The minimum concentration of antimicrobial agent needed to prevent visually discernible growth of a bacterial or fungal suspension. A. Minimum bactericidal concentration (MBC) B. Minimum inhibitory concentration (MIC) C. Both of these D. None of these

B. Minimum inhibitory concentration (MIC)

MUST KNOW!!! The minimum concentration of antimicrobial agent needed to yield a 99.9% reduction in viable colonyforming units of a bacterial or fungal suspension. A. Minimum bactericidal concentration (MBC) B. Minimum inhibitory concentration (MIC) C. Both of these D. None of these

A. Minimum bactericidal concentration (MBC)

MUST KNOW!!! Inoculum size for DISK DIFFUSION susceptibility testing: A. 1 x 104 CFU/spot B. 1.5 x 105 CFU/mL C. 1.5 x 108 CFU/mL D. 5 x 105 CFU/mL

C. 1.5 x 108 CFU/mL

MUST KNOW!!! Inoculum size for AGAR DILUTION susceptibility testing: A. 1 x 104 CFU/spot B. 1.5 x 105 CFU/mL C. 1.5 x 108 CFU/mL D. 5 x 105 CFU/mL

A. 1 x 104 CFU/spot

MUST KNOW!!! Inoculum size for BROTH DILUTION susceptibility testing: A. 1 x 104 CFU/spot B. 1.5 x 105 CFU/mL C. 1.5 x 108 CFU/mL D. 5 x 105 CFU/mL

D. 5 x 105 CFU/mL

MUST KNOW!!! 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

MUST KNOW!!! In the Kirby-Bauer disc diffusion susceptibility test, which variable is critical when testing Pseudomonas species for antibiotic susceptibility to aminoglycosides? A. Incubation temperature B. Duration of incubation C. Cation content of media D. Depth of agar

C. Cation content of media

MUST KNOW!!! n a disk diffusion susceptibility test, which of the following can result if disks are placed on the inoculated media and left at room temperature 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

MUST KNOW!! Quality control results for disk diffusion susceptibility tests yield the following results: aminoglycoside zones too small and penicillin zones too large. This is most likely due to the: A. Inoculum being too heavy B. Inoculum being too light C. pH of Mueller-Hinton agar being too low D. Calcium and magnesium concentration in the agar being too high

C. pH of Mueller-Hinton agar being too low

MUST KNOW!!! 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 previously used lot number, and all zone 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

MUST KNOW!!! 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

MUST KNOW!!! 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

MUST KNOW!!! Overall profile of antimicrobial susceptibility testing results of a specific microorganism to a battery of antimicrobial agents. A. Antibiotic profile B. Antibiogram C. Histogram D. Scattergram

B. Antibiogram

MUST KNOW!!! Staphylococcus aureus toxin which disrupts the smooth muscle in blood vessels and is toxic to erythrocytes, leukocytes, hepatocytes, and platelets: A. Alpha toxin B. Beta toxin C. Delta toxin D. Gamma toxin

A. Alpha toxin

Lysostaphin is used to differentiate Staphylococcus from which other genus? A. Streptococcus B. Stomatococcus C. Micrococcus D. Planococcus

C. Micrococcus

MUST KNOW!! A light yellow colony from a skin lesion grew aerobically and tested as catalase positive and coagulase negative. The organism gram stained as positive cocci in clusters. The organism was modified oxidase positive, bacitracin (0.04U) susceptible and resistant to lysostaphin. What is the identification of this organism? A. Staphylococcus aureus B. Micrococcus luteus C. Staphylococcus epidermidis D. Peptostreptococcus anaerobius

B. Micrococcus luteus

MUST KNOW!! Bacitracin resistance (0.04 unit) is used to differentiate: A. Micrococcus spp. from Staphylococcus spp. B. Staphylococcus spp. from Neisseria spp. C. Planococcus spp. from Micrococcus spp. D. Staphylococcus spp. from Streptococcus spp.

A. Micrococcus spp. from Staphylococcus spp.

MUST KNOW!! A wound (skin lesion) specimen obtained from a newborn grew predominantly β-hemolytic colonies of gram-positive cocci on 5% sheep blood agar. The newborn infant was covered with small skin eruptions that gave the appearance of a “scalding of the skin.” The gram-positive cocci proved to be catalase positive. Which tests should follow for the appropriate identification? A. Optochin, bile solubility, PYR B. Coagulase, glucose fermentation, DNase C. Bacitracin, PYR, 6.5% salt broth D. CAMP, bile-esculin, 6.5% salt broth

B. Coagulase, glucose fermentation, DNase

An outbreak of Staphylococcus aureus in the nursery department prompted the Infection Control Committee to proceed with an environmental screening procedure. The best screening media to use for this purpose would be: A. CNA agar B. THIO broth C. Mannitol salt agar D. PEA agar

C. Mannitol salt agar

MUST KNOW!! Inhibitor of Mannitol Salt Agar: A. Mannitol B. Phenol red C. Neutral red D. Sodium chloride

D. Sodium chloride

An outbreak of Staphylococcus aureus has occurred in a hospital nursery. In order to establish the epidemiological source of the outbreak, the most commonly used typing method is: A. Pulsed-field gel electrophoresis B. Serological typing C. Coagulase testing D. Catalase testing

A. Pulsed-field gel electrophoresis

An isolate of Staphylococcus aureus was cultured from an ulcer obtained from the leg of a diabetic 79-year-old female patient. The organism showed resistance to methicillin. Additionally, this isolate should be tested for resistance or susceptibility to: A. Erythromycin B. Gentamicin C. Vancomycin D. Kanamycin

C. Vancomycin

MUST KNOW!! Bacitracin A disks (0.04 unit) are used for the presumptive identification of which group of βhemolytic streptococci? A. Group A B. Group B C. Group C D. Group F

A. Group A

MUST KNOW!! Two blood cultures on a newborn grew β-hemolytic streptococci with the following reactions: § CAMP test = + § Hippurate hydrolysis = + § 6.5% NaCl = + § Bile esculin = negative § Bile solubility = negative § Bacitracin = resistant § PYR = negative § Trimethoprim–sulfamethoxazole = resistant Which is the most likely identification? A. Group A streptococci B. Group B streptococci C. Group D streptococci D. Nongroup A, nongroup B, nongroup D streptococci

B. Group B streptococci

!!An isolate recovered from a vaginal culture obtained from a 25-year-old female patient who is 8 months pregnant is shown to be a gram-positive cocci, catalase negative, and β-hemolytic on blood agar. Which tests are needed for further identification? A. Optochin, bile solubility, PYR B. Bacitracin, CAMP, PYR C. Methicillin, PYR, trehalose D. Coagulase, glucose, PYR

B. Bacitracin, CAMP, PYR

Which method is most useful for confirmation that a culture isolate is Group B streptococcus? !!! A. Southern blotting B. Polymerase chain reaction C. Direct hybridization D. Probe capture assay

C. Direct hybridization

Positive result for the hippurate hydrolysis test: A. Yellow B. Red C. Purple D. Black

C. Purple

S. pneumoniae and the viridans streptococci can be differentiated by which test? A. Optochin disk test, 5 μg/mL or less B. Bacitracin disk test, 0.04 unit C. CAMP test D. Bile esculin test

A. Optochin disk test, 5 μg/mL or less

Which test is used to differentiate the viridans streptococci from the group D streptococci and enterococci? A. Bacitracin disk test B. CAMP test C. Hippurate hydrolysis test D. Bile esculin test

D. Bile esculin test

The bile solubility test causes the lysis of: A. Streptococcus bovis colonies on BAP B. Streptococcus pneumoniae colonies on a blood agar plate C. Group A streptococci in broth culture D. Group B streptococci in broth culture

B. Streptococcus pneumoniae colonies on a blood agar plate

A sputum specimen from an 89-year-old male patient with suspected bacterial pneumonia grew a predominance of gram-positive cocci displaying alphahemolysis on 5% sheep blood agar. The colonies appeared donut shaped and mucoidy and tested negative for catalase. The most appropriate tests for a final identification are: !!!! A. Coagulase, glucose fermentation, lysostaphin B. Penicillin, bacitracin, CAMP C. Optochin, bile solubility, PYR D. Bile esculin, hippurate hydrolysis

C. Optochin, bile solubility, PYR

The Superoxol test is used as a rapid presumptive test for: !!!! A. Neisseria gonorrhoeae B. Neisseria meningitidis C. Neisseria lactamica D. Moraxella (Branhamella) catarrhalis

A. Neisseria gonorrhoeae

Appropriate transport medium for E.coli, Salmonella, Shigella and Y. enterocolitica: !!! 1. Cary-Blair 2. Stuart 3. Amies 4. Buffered glycerol-saline A. 1 only B. 2 and 3 C. 1, 2 and 3 D. 1, 2, 3 and 4

D. 1, 2, 3 and

Xylose lysine deoxycholate (XLD) agar is a highly selective medium used for the recovery of which bacteria? !!!! A. Staphylococcus spp. from normal flora B. Yersinia spp. that do not grow on Hektoen agar C. Enterobacteriaceae from gastrointestinal specimens D. Streptococcus spp. from stool cultures

C. Enterobacteriaceae from gastrointestinal specimens

At which pH does the methyl red (MR) test become positive? !!! A. 7.0 B. 6.5 C. 6.0 D. 4.5

D. 4.5

An organism gave the following reactions: !!!! § TSI: acid slant/acid butt; no H2S gas produced § Indole: positive § VP: negative § Citrate: negative § Urea: negative § Motility: positive § Lysine decarboxylase: positive This organism most likely is: A. Klebsiella pneumoniae B. Shigella dysenteriae C. Escherichia coli D. Enterobacteria cloacae

C. Escherichia coli

A sputum culture from an alcoholic seen in the ER grows gray, mucoid, stringy colonies on sheep blood agar. The isolate grows readily on MacConkey agar and forms mucoid, dark pink colonies. The colonies yield the following test results: § ONPG: + § Indole: - § Glucose: + § Oxidase: - § Citrate: + § VP: + The organism is most likely: A. Edwardsiella tarda B. Klebsiella pneumoniae C. Escherichia coli D. Proteus vulgaris

B. Klebsiella pneumoniae

Which of the following sets of tests best differentiates Salmonella and Citrobacter species? !!! A. KCN, malonate, beta-galactosidase, lysine decarboxylase B. Dulcitol, citrate, indole, H2S production C. Lactose, adonitol, KCN, motility D. Lysine decarboxylase, lactose, sucrose, malonate, indole

A. KCN, malonate, beta-galactosidase, lysine decarboxylase

Which biochemical tests should be performed in order to identify colorless colonies growing on MacConkey agar (swarming colonies on blood agar) from a catheterized urine specimen? A. Indole, phenylalanine deaminase, and urease B. Glucose, oxidase, and lactose utilization C. Phenylalanine deaminase and bile solubility D. H2S and catalase

A. Indole, phenylalanine deaminase, and urease

!!!!! Greater than 100,000 CFU/mL of a gram-negative bacilli were isolated on MacConkey from a urine specimen. Biochemical results are as follows: § Glucose: acid, gas produced § Indole: negative § Urea: positive § TDA: positive § H2S: positive The organism is most likely: A. Morganella morganii B. Proteus mirabilis C. Proteus vulgaris D. Providencia stuartii

B. Proteus mirabilis

!!! Three blood cultures taken from a 30-year-old cancer patient receiving chemotherapy and admitted with a urinary tract infection grew lactose-negative, motile, gram-negative rods prior to antibiotic therapy. Given the following biochemical reactions, which is the most likely organism? § H2S (TSI): positive § VP: negative § DNase: positive § Gelatin hydrolysis: positive § Ornithine decarboxylase: negative § Indole: positive § Citrate: negative § Phenylalanine deaminase: positive § MR: positive § Urease: positive A. Proteus vulgaris B. Proteus mirabilis C. Serratia marcescens D. Klebsiella pneumoniae

A. Proteus vulgaris

A 64-year-old male with lymphoma has a positive blood culture at 18 hours incubation. The organism is a non-lactose fermenting gram-negative bacillus on MacConkey agar. Further testing gives the following reactions: !!! § Oxidase: negative § TSI: alkaline/acid, no hydrogen sulfide § Motility: positive § Indole: positive § Citrate: positive § Ornithine decarboxylase: negative § Urea: positive § Phenylalanine deaminase: positive § VP: positive The genus is: A. Morganella B. Proteus C. Providencia D. Serratia

C. Providencia

A favored energy source for many enteric pathogens, but it is not utilized by many other nonpathogenic enteric organisms. !!! A. Lysine B. Mannitol C. Phenol red D. Bile salts

Mannitol

Fever, abdominal cramping, watery stools, and fluid and electrolyte loss preceded by bloody stools 2–3 days before is characteristic of shigellosis but may also result from infection with: A. Campylobacter spp. B. Salmonella spp. C. Proteus spp. D. Yersinia spp.

A. Campylobacter spp.

Which group of tests best differentiates Helicobacter pylori from C. jejuni? A. Catalase, oxidase, and Gram stain B. Catalase, oxidase, and nalidixic acid sensitivity C. Catalase, oxidase, and cephalothin sensitivity D. Urease, nitrate, and hippurate hydrolysis

D. Urease, nitrate, and hippurate hydrolysis

The following results were obtained from a pure culture of gram-negative rods recovered from the pulmonary secretions of a 10-year-old cystic fibrosis patient with pneumonia: !!! § Oxidase: positive § Glucose OF (open): positive § Pigment: red (nonfluorescent) § Growth at 42°C: positive § Motility: positive § Gelatin hydrolysis: positive § Arginine dihydrolase: positive § Flagella: polar, monotrichous Which is the most likely organism? A. Burkholderia pseudomallei B. Pseudomonas stutzeri C. Burkholderia cepacia D. Pseudomonas aeruginosa

D. Pseudomonas aeruginosa

100

A 17-year-old female with cystic fibrosis is diagnosed with pneumonia. A sputum sample grew gramnegative bacilli with yellow, smooth colonies that have the following biochemical reactions: !! § Oxidase: positive § TSI: alk/alk § Glucose: oxidized § Fluorescence: negative § Lysine decarboxylase: positive The most likely organism is: A. Burkholderia cepacia B. Klebsiella pneumoniae C. Shewanella putrefaciens D. Stenotrophomonas maltophilia

A. Burkholderia cepacia

other names parasitology

Yves Laure Pimentel · 70問 · 2年前

other names parasitology