Part 1 gyapon Flashcards
Select the media of choice for recovery of Vibrio cholerae from a stool specimen:
a. MacConkey agar and thioglycolate media
b. TCBS and alkaline peptone water
c. Blood agar and selenite F broth
d. Cycloserine-cefoxitin-fructose agar
b. TCBS and alkaline peptone water
Blood agar plates are ideally prepared with 5% RBCs obtained from:
A. Sheep
B. Horses
C. Humans
D. Dogs
A. Sheep
Cycloserine-cefoxitin-fructose agar (CCFA) is used for the recovery of:
a. Yersinia enterocolitica
b. Yersinia intermedia
c. Clostridium perfringens
d. Clostridium difficile
d. Clostridium difficile
Prereduced and Vitamin K1 supplemented blood agar plates are recommended isolation media for:
a. Mycobacterium marinum and M. avium
b. Bacteroides, Peptostreptococcus and Clostridium spp.
c. Proteus spp.
d. Enterococcus spp.
b. Bacteroides, Peptostreptococcus and Clostridium spp.
Which procedure is appropriate for culture of genital specimens in order to recover Chlamydia spp.?
a. Inoculate cycloheximide treated McCoy’s cells
b. Plate onto blood and chocolate agar
c. Inoculate into thioglycolate broth
d. Plate onto modified Thayer-Martin agar within 24 hours
a. Inoculate cycloheximide treated McCoy’s cells
The Voges-Proskauer (VP) test detects which end product of glucose fermentation?
A. Acetoin
B. Nitrite
C. Acetic acid
D. H2S
A. Acetoin
Which of the following reagents is added to detect the production of indole?
a. p-dimethylaminobenzaldehyde
b. MR
c. Bromcresol purple
d. Cytochrome oxidase
a. p-dimethylaminobenzaldehyde
Which genera are positive for phenylalanine deaminase?
a. Enterobacter, Escherichia and Salmonella
b. Morganella, Providencia and Proteus
c. Klebsiella and Enterobacter
d. Proteus, Escherichia and Shigella
b. Morganella, Providencia and Proteus
An isolate of E.coli recovered from the stool of a patient with severe bloody diarrhea should be tested for what sugar before sending to a reference laboratory for serotyping?
A. Sorbitol
B. Mannitol
C. Raffinose
D. Sucrose
A. Sorbitol
Which genera of Enterobacteriacea are usually nonmotile at 36C?
a. Shigella, Klebsiella and Yersinia
b. Escherichia, Edwardsiella and Enterobacter
c. Proteus, Providencia and Salmonella
d. Serratia, Morganella and Hafnia
a. Shigella, Klebsiella and Yersinia
Which single test best separates Klebsiella oxytoca from Klebsiella pneumoniae?
a. Urease
b. Sucrose
c. Citrate
d. Indole
d. Indole
The characteristics of being lactose negative, citrate negative, urease negative, lysine decarboxylase negative, and nonmotile best describe which organism?
a. Proteus vulgaris
b. Yersinia pestis
c. Shigella dysenteriae
d. Aeromonas hydrophila
c. Shigella dysenteriae
In grouping Shigella organisms, agglutination by group B antisera indicates that the species is:
a. Shigella dysenteriae
b. Shigella flexneri
c. Shigella boydii
d. Shigella sonnei
b. Shigella flexneri
Pus with blue green-color was aspirated from empyema. A Gram stain of the aspirated material showed many WBCs and numerous gram-negative bacilli. The most likely etiologic agent in this case would be:
A. Legionella pneumophila
B. Pseudomonas auruginosa
C. Morganella morganii
D. Acinetobacter anitratus
B. Pseudomonas auruginosa
A visitor to South America returns with diarrhea, and infection with Vibrio cholerae is suspected. Select the best media for recovery and identification of this organism.
A. MacConkey agar
B. Blood Agar
C. TCBS agar
D. Xylose lysine desoxycholate agar
C. TCBS agar
What atmospheric condition is needed to recover Campylobacter spp. from specimens inoculated onto a Campy-selective agar at 35-37C and 42C?
A. 5% O2, 10% CO2, and 85% N2
B. 10% O2, 10% CO2, and 80% N2
C. 20% O2, 20% CO2, and 60% N2
D. 20% O2, 5% CO2, and 75% N2
A. 5% O2, 10% CO2, and 85% N2
Which medium should be used to recover Bordetella pertussis from a nasopharyngeal specimen?
a. Chocolate agar
b. Blood agar
c. MacConkey agar
d. Bordet-Gengou agar
d. Bordet-Gengou agar
Which media is recommended for the recovery of Brucella spp. from blood and bone marrow specimens?
a. Biphasic Castaneda bottles with Brucella broth
b. Blood culture bottles with Brucella broth
c. Bordet-Gengou agar plates and thioglycolate broth
d. Blood culture bottles with thioghlycolate broth
a. Biphasic Castaneda bottles with Brucella broth
In addition to CO2 requirement and biochemical characteristics, Brucella melitensis and Brucella abortus are differentiated by growth on media containing which two dyes?
a. Basic fuchsin and thionin
b. Methylene blue and crystal violet
c. Carbol fuchsin and iodine
d. Safranin and methylene blue
a. Basic fuchsin and thionin
Which medium is best for recovery of Legionella pneumophila from clinical specimens?
a. Chocolate agar
b. Bordet-Gengou agar
c. New yeast extract agar
d. Buffered charcoal yeast extract agar
d. Buffered charcoal yeast extract agar
Which Haemophilus sp. is difficult to isolate and recover from genital ulcers and swollen lymph nodes?
a. H. aphrophilus
b. H. haemolyticus
c. H. ducreyi
d. H. parahaemolyticus
c. H. ducreyi
A spherical, gram-positive coccus that is catalase positive, non-motile and unable to produce acid from glucose anaerobically is best identified as a member of the genus:
A. Micrococcus
B. Staphylococcus
C. Veillonella
D. Moraxella
A. Micrococcus
Slime production is associated with which Staphylococcus species?
A. S. aureus
B. S. epidermidis
C. S. intermedius
D. S. saprophyticus
B. S. epidermidis
Bacitracin A disks (0.04 units) are used for the presumptive identification of which group of beta-hemolytic Streptococcus spp.?
A. Group A
B. Group B
C. Group C
D. Group F
A. Group A
Streptococcus pneumonia and Viridans streptococci can be differentiated by which test?
A. Optochin disk test
B. Bacitracin disk test
C. CAMP test
D. Bile esculin test
A. Optochin disk test
The salt tolerance test (6.5% salt broth) is used to presumptively identify:
A. Streptococcus pneumonia
B. Streptococcus bovis
C. Streptococcus equines
D. Group D streptococci (enterococci)
D. Group D streptococci (enterococci)
The Quellung test is used to identify which Streptococcus spp.?
A. S. pyogenes
B. S. agalactiae
C. S. sanguis
D. S. pneumoniae
D. S. pneumoniae
The L-pyrolidonyl-B-naphtylamide (PYR) hydrolysis test is a presumptive test for which streptococci?
A. Group A and D (enterococcus) streptococci
B. Group A and B beta-hemolytic streptococci
C. Non-Group A and B beta-hemolytic streptococci
D. Streptococcus pneumoniae and Group D streptococci (nonenterococcus)
A. Group A and D (enterococcus) streptococci
Alpha-hemolytic streptococci recovered from a wound were found to be penicillin resistant. Given the following results, what is the most likely identification?
Bile esculin (+) 6.5% salt (+) PYR (+) Bile solubility (0) SXT (R)
a. Enterococcus faecalis
b. Streptococcus pneumoniae
c. Streptococcus bovis
d. Group B streptococci
a. Enterococcus faecalis
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 is most likely:
a. Staphylococcus aureus
b. Streptococcus pneumoniae
c. Streptococcus pyogenes (group A)
d. Streptococcus agalactiae (group B)
d. Streptococcus agalactiae (group B)
Modified Thayer-Martin (MTM) media is used primarily for the selective recovery of which organism from genital specimens?
A. Neisseria gonorrhea
B. Neisseria lactamica
C. Neisseria sicca
D. Neisseria flavescens
A. Neisseria gonorrhea
The superoxol test is used as a presumptive test for:
A. Neisseria gonorrheae
B. Neisseria meningitidis
C. Neisseria lactamica
D. Moraxella catarrhalis
A. Neisseria gonorrheae
Culture on Modified Thayer-Martin (MTM) medium of a vaginal swab produced several colonies of gram-negative diplococci that were catalase and oxidase positive and superoxol negative. Given the following carbohydrate reactions, select the most likely identification:
Glucose (+) Maltose (+) Sucrose (0) Fructose (0) Lactose (+)
A. N. gonorrheae
B. N. sicca
C. N. flavescens
D. N. lactamica
D. N. lactamica
Bacillus anthracis and Bacillus cereus can best be differentiated by which tests?
a. Motility and beta hemolysis on blood agar plate
b. Oxidase and alpha hemolysis on blood agar plate
c. Lecithinase and glucose
d. Lecithinase and catalase
a. Motility and beta hemolysis on blood agar plate
A non-spore-forming, slender gram-positive rod forming palisades and chains was recovered from a vaginal cultures and grew well on tomato juice agar. The most likely identification is:
a. Lactobacillus spp.
b. Bacillus spp.
c. Neisseria spp.
d. Streptococcus spp.
a. Lactobacillus spp.
A gram-positive branching filamentous organism recovered from a sputum specimen was found to be positive with modified acid-fast stain method. What is the most likely presumptive identification?
a. Bacillus spp.
b. Nocardia spp.
c. Corynebacterium spp.
d. Listeria spp.
b. Nocardia spp.
Which of the following organisms is the cause of Lyme disease?
A. Treponema pallidum
B. Neisseria meningitidis
C. Babesia microti
D. Borrelio burgdorferi
D. Borrelio burgdorferi
Primary atypical pneumonia is caused by:
A. Streptococcus pneumoniae
B. Mycoplasma pneumoniae
C. Klebsiella pneumoniae
D. Mycobacterium tuberculosis
B. Mycoplasma pneumoniae
Which organism typically produces “fried-egg” colonies on agar within 1-5 days of culture from a genital specimen?
A. Mycoplasma hominis
B. Borrelia burgdorferi
C. Leptospira interrogans
D. Treponema pallidum
A. Mycoplasma hominis
A direct smear from a nasopharyngeal swab stained with Loeffler’s methylene blue stain showed various letter shapes and metachromatic granules. The most likely identification is:
A. Corynebacterium spp.
B. Nocardia spp.
C. Listeria spp.
D. Gardnerella spp.
A. Corynebacterium spp.
Which of the following is the best rapid, noncultural test to perform when Gardnerella vaginalis is suspected in a patient with vaginosis?
A. 10% KOH
B. 3% H2O2
C. 30% H2O2
D. All of these
A. 10% KOH
A gram-positive spore-forming bacillus growing on blood agar anaerobically produces a double zone of hemolysis and is positive for lecithinase. What is the presumptive identification?
A. Bacteroides ureolyticus
B. Bacteroides fragilis
C. Clostridium perfringens
D. Clostridium difficile
C. Clostridium perfringens
Which spore type and location is found on C. tetani?
A. Round, terminal spores
B. Round, subterminal
C. Ovoid, subterminal spores
D. Oval, terminal spores
A. Round, terminal spores
Which Clostridium spp. is most often recovered from a wound infection with gas gangrene?
A. C. sporogenes
B. C. sordellii
C. C. novyi
D. C. perfringens
D. C. perfringens
A Gram stain smear taken from the periodontal pockets of a 30-year-old male with poor dental hygiene showed sulfur granules containing gram-positive rods (short diphtheroids and some unbranched filaments). Colonies on blood agar resembled “molar teeth” in formation. The most likely organism is:
A. Actinomyces israelii
B. Propionibacterium acnes
C. Streptococcus intermedius
D. Peptostreptococcus anaerobius
A. Actinomyces israelii
Mycobacteria stained with Ziehl-neelsen or Kinyuon methods using a methylene blue counterstain, are seen microscopically as:
A. Bright red rods against a blue background
B. Bright yellow rods against a yellow background
C. Orange-red rods against a black background
D. Bright blue rods against a pink background
A. Bright red rods against a blue background
Acid-fast staining of a smear prepared from a digested sputum showed slender, slightly curved, beaded red mycobacterial rods. Growth on Middlebrook 7H10 slants produced buff-colored microcolonies with a serpentine pattern after 14 days at 37 oC. Niacin and nitrate reduction tests were positive. What is the most probable presumptive identification?
A. Mycobacterium tuberculosis
B. Mycobacterium ulcerans
C. Mycobacterium kansasii
D. Mycobacterium avium complex
A. Mycobacterium tuberculosis
All of the following Mycobacterium spp. produce the enzyme required to convert niacin to niacin ribonucleotide except:
A. M. kansasii
B. M. tuberculosis
C. M. avium
D. All of these
B. M. tuberculosis
Which nonpathogenic Mycobacterium sp. is isolated most often from clinical specimens and is called the “tapwater bacillus”?
A. M. kansasii
B. M. avium
C. M. leprae
D. M. gordonae
D. M. gordonae
All of the following paired infections and vectors are correct, EXCEPT:
A. Rocky Mountain Spotted Fever: tick
B. Rickettsialpox: mite
C. Trench fever: lice
D. Epidemic typhus: mite
D. Epidemic typhus: mite
For which clinical specimens is the potassium hydroxide direct mount technique for examination of fungal elements used?
A. Skin
B. CSF
C. Blood
D. Bone marrow
A. Skin
The India ink stain is used as a presumptive test for the presence of which organism?
A. Aspergillus niger in blood
B. Cryptococcus neoformans in CSF
C. Histoplasma capsulatum in CSF
D. Candida albicans in blood/body fluids
B. Cryptococcus neoformans in CSF
Which of the following yeast enzymes is detected using birdseed (niger seed) agar?
A. Phenol oxidase
B. Catalase
C. Urease
D. Nitrate reductase
A. Phenol oxidase
Which of the following yeasts is characteristically positive for germ tube production?
A. Candida tropicalis
B. Candida pseudotropicalis
C. Cryptococcus neoformans
D. Candida albicans
D. Candida albicans
Dimorphic fungi are found in the infected tissue in which form?
A. Mold phase
B. Yeast phase
C. Encapsulated
D. Latent
B. Yeast phase
The mycelial form of which dimorphic mold produces thick-walled, rectangular, or barrel-shaped alternate arthroconidia?
A. Coccidioides immitis
B. Sporothrix schenckii
C. Histoplasma capsulatum
D. Blastomyces dermatitidis
A. Coccidioides immitis
The yeast form of which dimorphic fungus appears as oval or elongated cigar shaped, some with multiple buds?
A. Coccidioides immitis
B. Sporothrix schenckii
C. Histoplasma capsulatum
D. Blastomyces dermatitidis
B. Sporothrix schenckii
The yeast form of which dimorphic mold shows a large parent yeast cell surrounded by smaller budding yeast cells?
A. Paracoccidioides brasiliensis
B. Sporothrix schenckii
C. Coccidioides immitis
D. Histoplasma capsulatum
A. Paracoccidioides brasiliensis
Tinea versicolor is a skin infection caused by:
A. Malassezia furfur
B. Tricophyton rubrum
C. Trichophyton schoenleinii
D. Microsporum gypseum
A. Malassezia furfur
Which Trichophyton sp. causes the favus type of tinea capitis seen in Scandinavian countries and in the Appalachian region of the United States?
A. T. verrucosum
B. T. violaceum
C. T. tonsurans
D. T. schoenleinii
D. T. schoenleinii
The hair baiting test is used to differentiate which two species of Trichophyton that produce red colonies on Sabouraud’s agar plates?
A. T. mentagrophytes and T. rubrum
B. T. tonsurans and T. schoenleinii
C. T. tonsurans and T. violaceum
D. T. verrucosum and T. rubrum
A. T. mentagrophytes and T. rubrum
Which virus is the most common etiological agent of viral respiratory diseases in infants and children?
A. Respiratory syncytial virus
B. Measles virus
C. Coxsackie A virus
D. Coxsackie B virus
A. Respiratory syncytial virus
Which virus belonging to the Reoviridae group causes gastroenteritis in infants and young children but asymptomatic infection in adults?
A. Coxsackie B virus
B. Rotavirus
C. Respiratory syncytial virus
D. Rhabdovirus
B. Rotavirus
A very small, single-stranded DNA virus that causes a febrile illness with a rash and is called the fifth childhood disease after rubeola, rubella, varicella and roseola is:
A. Rotavirus
B. Adenovirus type 40
C. Coxsackie A virus
D. Parvovirus B19
D. Parvovirus B19
Which virus is associated with venereal and respiratory tract warts and produces lesions of the skin and mucous membranes?
A. Polyomavirus
B. Poxvirus
C. Adenovirus
D. Papillomavirus
D. Papillomavirus
Which technique is most widely used for the confirmation of infection with human immunodeficiency virus (HIV)?
A. Western blot assay
B. ELISA
C. Complement fixation
D. Polymerase chain reaction
A. Western blot assay
