• What culture medium is used in Agar Dilution • What is test that provides a high probability for the

Susceptibility Testing for Neisseria meningitidis? presumptive identification of the β-hemolytic GAS
o MHA plus 5% sheep blood and the nonhemolytic group D streptococci?
• What culture medium is used in Disk Diffusion o PYR
Susceptibility Testing to detect Staphylococci (to • It was originally designed for US space exploration
detect methicillin-resistance)? efforts of the 1970s as an onboard test system for
o MHA (add 2% NaCl) spacecraft exploring other planets for life.
• What culture medium is used in Disk Diffusion o VITEK system
Susceptibility Testing to detect Enterobacteriaceae? • In this biosafety level examples are M. tuberculosis,
o MHA St. Loius encephalitis virus, and Coxiella burnetii.
• In reading susceptibility testing plates, Proteus spp., o Biosafety level 3
may swarm over the surface of the plate, in these • There is a blood spill on a table top, what should be
cases, the swarming haze is ignored and zones are done properly?
measured at the point where growth is inhibited. o Use a paper towel to allow the blood to be
o True absorbed first, afterwards apply phenol and
• Which test is used to detect inducible clindamycin dry
resistance? • A medtech intern was told to sterilize some materials
o D-zone test and she noticed that they are heat sensitive. What is
• Which test is used to detect Streptococcus the best method she can perform?
pneumoniae/penicillin resistance? o Filtration method
o Oxacillin disk screen • An organism are being observed are likely to cause
• What enzyme is detected in the chromogenic life-threatening infection with no known modes of
cephalosporinase test? transmission. What BSL level should be used?
o Beta-lactamases o Biosafety Level 4
• After incubation and determination of the • Group A β-hemolytic Streptococcus, for example, is
antimicrobial agent’s MIC, an aliquot from each not routinely tested because it is universally
tube or well in the dilution series demonstrating susceptible to penicillin, the drug of choice in
inhibition of visible bacterial growth is subculture to treating infections caused by this bacterium.
an enriched agar medium. o True
o Minimal Bactericidal Concentration test • These antibiotics act by binding to PBPs,
• In Nucleic acid hybridization test, what is referred to bifunctional transglycosylases-transpeptidases
as the target strand? responsible for the crosslinking of glycan strands
o Template and backbone peptide strands, respectively.
• This is used to detect RNA molecules, which are o β-Lactams
almost always transcript (messenger RNA, mRNA). • These are antibiotics that affect DNA replication by
o Northern blot targeting topoisomerases II (DNA gyrase) and IV.
• A technique whereby chromosomal DNA could be o Quinolones
separated by agarose gel electrophoresis and then • In gram positive bacteria, the β-lactamases are
transferred to and immobilized on a nitrocellulose localized to the periplasmic space, where they act on
membrane. incoming β-lactam antibiotics.
o Southern Blot o False
• • In this hybridization method, DNA or RNA • Efflux pumps are found in which type of bacteria?
transcript can be detected directly in tissue with o gram-positive and gram negative
labeled probes. The technique is often performed • This reversibly inhibits protein translation in bacteria
directly in tissue that has been embedded in paraffin. by binding to the 30S ribosomal subunit and
• In situ hybridization The goal of this step is to blocking entry of amino acyl tRNA molecules into
hybridize, oligonucleotide primers to the denatured, the A site of the ribosome, thus preventing the
single-stranded target DNA strands. incorporation of amino acid residues into elongating
o Primer Annealing peptide chains.
o Tigecycline
• They bind close to the peptidyl transferase site of • PYR positive
the 50S subunit of the bacterial ribosome inhibiting o S. pneumoniae
RNA-dependent protein synthesis. o S. pyogenes
o Ketolides o S. agalactiae
• This antibiotic in combination with ciprofloxacin o S. dysgalactiae
and clindamycin are reported to be useful for the • Which of the following test for Streptococcus relies
treatment of bacterial infections relevant to on the enhanced hemolysis occurring when the β-
biowarfare or bioterrorism, such as inhalational lysin and the hemolysin produced by GBS are in
anthrax. contact. S. aureus is inoculated in a straight line in
o Rifamycin the center of an SBA?
• This blocks the step leading to the formation of o CAMP test : ARROW HEAD FORMATION
Tetrahydrofolate by preventing the dihydrofolate POSITIVE
reductase–mediated recycling of folate coenzymes. • The only species of Streptococcus that is PYR-
o Trimethoprim positive.
• In autoclaving, once the sterilization cycle is o Strep. Pyogenes
completed, molten agar is allowed to cool to • Which test will differentiate Streptococcus
approximately_______ before being distributed to pneumoniae from other Viridans streptococci?
individual petri plates. o Optochin test
o 50C • Catalase (-), beta hemolysis, PYR (-), Bacitracin (R),
• This type of culture media contains growth hippurate hydrolysis (+)
enhancers that are added to nonselective agar to o Strep. Agalactiae: CAMP POSITIVE
allow fastidious organisms to flourish. • When it comes to detection of oxacillin resistance in
o Enriched media Staphylococcus aureus, laboratories should be able
• Gram stain of expectorated sputum reveals less than to..
25 white blood cells (WBCs) and more than 10 o report susceptibilities for penicillin and
epithelial cells per low power field. cefoxitin
o Reject the specimen o cefoxitin is used to detect methicillin
• This process deposits cellular elements and resistance
microorganisms from the specimen onto the surface o Screen using oxacillin-salt agar plate
of a glass slide as a monolayer. • The biochemical tests performed on a gram-positive
o Cytocentrigufation bacillus were consistent with Corynebacterium
• It is an open fronted type of cabinet that uses an diphtheriae. As a definitive test, the laboratory
exhaust fan to allow movement of air going through scientist should now:
the open front o Perform an Elek test to determine whether the
o Class I organism produces exotoxin
• It is appropriate for processing chemicals, • The macrolide test is used for the following except:
radioisotopes and carcinogens aside from biological o erythromycin resistant and clindamycin
samples treated with toxic or hazardous chemicals. resistant
Airflow 0% recirculated and 100% exhausted. • Corynebacterium species often appear as
o Class II, Type B2 ______________ on Gram stain.
• Bacitracin susceptible, SMZ susceptible, Bile o Pleomorphic gram-positive club-shaped bacilli
esculin hydrolysis negative, CAMP negative, that appear in palisades or in V and L
Leucine aminopeptidase positive, growth in 6.5% formations
NaCl negative • What bacteria will give a reaction of Alkaline
o S. pneumoniae phosphatase negative, PYR positive, Ornithine
• Which Clostridium spp. causes pseudomembranous decarboxylase positive, clumping factor positive?
colitis or antibiotic-associated colitis? o S. lugdunensis
o C. difficile • A non–spore-forming, slender gram-positive rod
• The tube coagulase test is incubated at 37C for 4hrs forming palisades and chains was recovered from a
to detect clot formation, what should be done if no vaginal culture and grew well on tomato juice agar.
clot is seen after 4 hours? The most likely identification is:
o Incubate tubes at room temperature overnight o Lactobacillus spp.
• This Mycobacterium spp has been reported as a • The potentially lethal intoxication type of food
cause of disseminated infections in patients with poisoning often associated with improperly canned
AIDS. It has also been associated with enteritis, food is caused by
genital and soft tissue infections in HIV-positive and o Clostridium botulinum
HIV-negative immunocompromised patients. • This is produced by C. perfringens, cause necrosis
o Mycobacterium genavense of the tissue and allow deeper penetration by the
• The typical presentation of a tender red or blue- organisms.
red subcutaneous nodule, or swimming pool o α-toxin
granuloma, usually occurs on the elbow, knee, toe, • Honey contaminated with the C. botulinum spores
or finger. is the food most commonly associated with infant
o Mycobacterium marinum botulism
• It is the most frequently recovered Corynebacterium o TRUE
sp. from human clinical material. Often associated • The coagulase test is used to differentiate.
with prosthetic joint infection and has been reported o Staphylococcus aureus from Staphylococcus
to cause blood stream infection and endocarditis. epidermidis
o C. amycolatum • The spores oval and terminal or subterminal with
• Acid fast rods in nasal mucosa of patients with drumstick or tennis racket appearance. What is the
nodular variety of Hansen’s Disease: bacteria?
o Mycobacterium leprae: FOOTPADS OF o Clostridium tetani
MOUSE CULTURE/ ARMADILLO • What is the bacteria with nonhemolytic; barnyard
• Was the most common cause of cervical or horse stable odor?
lymphadenitis in children o Clostridium difficile
o Mycobacterium scrofulaceum • Streptococcus pyogenes is a toxigenic bacterium
• Which of the following is included in Amsel's causing a variety of diseases. Which of the following
clinical criteria used to diagnosis bacterial statements best characterizes this organism?
vaginosis? o It secretes erythrogenic toxin that causes the
o homogeneous, thin, white discharge that characteristic signs of scarlet fever
smoothly coats the vaginal walls • Which of the following shows a double zone of
o clue cells : GARDNERELLA VAGINALIS beta hemolysis on BAP?
o pH of vaginal fluid greater than 4.5 o Clostridium perfringens
o fishy odor of vaginal discharge before or after • Which of the following is Lecithinase positive?
addition of 10% potassium hydroxide o Clostridium perfringens
• It is the only Erysipelothrix spp known to cause • A patient had surgery 2 months ago to put in a
disease in humans. pacemaker. He felt fine for 1 month, but over the
o Erysipelothrix rhusiopathiae past month, he has been feeling worse. He is running
• Catalase positive bacilli a low-grade fever, tires easily, and has worsening
o Listeria heart murmurs. Which of the following
o Corynebacterium staphylococcal organisms causes subacute bacterial
• Gram positive rod, spore-former endocarditis that occurs 2 months or more after heart
o Bacillus surgery?
• A useful test for differentiating S. agalactiae from o Staphylococcus epidermidis
other β-hemolytic streptococcus. • The ends of the cells may be pointed, bent, club-
o Hippurate Hydrolysis shaped, spatulated, or bifurcated (forked). What is
• Clinical Infections associated with S, pyogenes the bacteria?
o Bacterial pharyngitis o Bifidobacterium spp.
o Pyodermal infections • Most species produce butyric acid and convert
o Necrotizing Fasciitis threonine to propionic acid. What is the bacteria?
• Which of the following is/are catalase-negative, o Fusobacterium spp.
gram-positive cocci that are usually arranged in pairs • Common cause of diphtheroid prosthetic heart valve
or chains? endocarditis.
o Enterococcus and Streptococcus o C. jeikeium
• What is the dark pigment produced by Prevotella • In serological test for syphilis, the nontreponemal
spp.? test detect...
o protoporphyrin o reaginic antibodies
• C. diptheriae can be tested for its toxins by using: • testWhen IFA is positive for Borrelia burgdorferi,
o ELEK what test con be done to confirm?
• Staphylococcal virulence that is responsible for o IgM or IgG Western blot
suppressing phagocytosis • The presence of sphingophospholipids in the cell
o Leucocidin wall is unique to the group. They are true
• True for S. agalactiae fermenters and can also oxidize some carbohydrates
o seen in upper GI tract o Sphingobacterium
• True for staphylococcus • Borreliae can be recovered by culture on...
o resistant to bacitracin o Kelly medium
• Staphylococcal enzyme responsible for dissolving o animal inoculation (involving suckling Swiss
clot mice or suckling rats)
o Staphylokinase • Which of the following is the gold standard test for
• True for MSA: the detection of leptospiral antibodies
o 48 hours of incubation o microscopic agglutination test
o 7.5% salt • produce a characteristic pink to coral pigment and
o phenol red as indicator can use methanol as a sole source of carbon and
• Alpha hemolytic streptococcus isolated in energy
nasopharynx. Where should you incubate the o Methylobacterium
culture media? • Which of the following Vibrio spp. would you
o Carbon dioxide expect to be most likely isolated from a blood
• What culture media is best used for isolating culture?
staphylococcus subjected for catalase test? o V. vulnificus
o chocolate agar • Oxidase positive, acid from glucose positive
• Staphylococcal enzyme responsible for the binding o Aeromonas
of immunoglobulins that can weaken immunity? o Vibrio
o Protein A o .Plesiomonas
• This organism is known for its quelling reaction. It • Which of the following members of
is also alpha hemolytic streptococci. enterobacteriaceae was first recognized to have
o S. pneumoniae carbapenamases?
• This mycobacteria requires mycobactin- o Klebsiella pneumoniae
supplemented medium for primary isolation • O/129 susceptible, string test positive, inositol
o M. avium complex fermentation negative
• Has been recovered from hot and cold water taps o Vibrio
(including water storage tanks of hospitals) and birds • Which organism is an opportunistic pathogen that
o M. xenopi causes wound and urinary tract infections and may
• The following are characteristic of C. violaceum cause the production of kidney stones?
except: o Proteus mirabilis
o oxidase negative • Which of the following medium are used to
• Strong urease activity differentiate the colonies of Vibrio cholerae and V
o Helicobacter parahaemolyticus?
• Glycogen inclusions +, elementary body round, sulfa o Thiosulphate-citrate-bile-sucrose
drug sensitivity = • On HE agar, lactose-fermenting species produce
o Chlamydia trachomatis what color of colonies?
• Which of the following exhibit a distinctive yellow o Yellow
colonies?
o Chryseobacterium indologenes
• Routine screening of fecal specimens for enteric • The following are true about Acinetobacter except:
gastroenteritis causing pathogens includes detection o A. oxidase negative, catalase positive, and
of.... nonmotile
o Salmonella o B. gram-positive cocci in smears made from
o Shigella blood culture bottles
o Campylobacter o C. strictly aerobic, and they appear as gram-
• Which of the following property(ies) is/are seen in negative coccobacilli
the members of family Enterobacteriaceae? o D. None of these are correct
o They are oxidase-negative • Which of the following causes otitis externa in
• Oxidase +, glucose oxidation (saccharolytic) +, swimmers or divers?
growth at 42C, Fluorescein + o Pseudomonas aeruginosa
o Pseudomonas aeruginosa • Serologic typing is best performed on a colony taken
• Which of the following is the best test for detection from a pure culture growing on which culture
of Bordetella pertusis? media?
o PCR o SBA
• Diagnosis of Pontiac fever is by... • Lavender to lavender-green colonies on SBA
o Serology o Stenotrophomonas maltophilia
• ESBL is confirmed if the activity of cefotaxime and • Grape like or sweet odor
ceftazidime is restored when tested in combination o Pseudomonas aeruginosa
with what antibiotic? • Oxidase -, glucose oxidation -, motility -, growth at
o Clavulanic acid 42C -, DNase -
• Which of the following is Oxidase positive? o Acinetobacter iwofii
o Aeromonas • A unique characteristic of many isolates of
• The colonies are described as wagon wheel Pseudomonas useful in identification is
appearance on CHOC agar o fluorescent green pigment
o Moraxella catarrhalis • Which biochemical tests are needed to differentiate
• Commonly found in the nasopharynx of infants and Burkholderia cepacia from S. maltophilia?
children and, is commonly encountered in o Pigment on blood agar, oxidase, DNase
meningococcal carrier surveys • Microscope used to observe leptospires
o Neisseria lactamina o Dark field and Phase contrast
• A delayed positive citrate reaction is a major • Diagnosis of borreliosis is readily made by
characteristic of... observing blood films stained with...
o Hafnia o Giemsa or Wrights
• Which of the following is citrate positive? • Serovars A, B, Ba, C
o Klebsiella pneumoniae subsp. Pneumoniae o Chlamydia trachomatis
o Klebsiella oxytoca • Psittacosis
o Klebsiella pnuemoniae subsp. Ozaenae o Chlamydophila psittaci
• Which if the following is indole positive? • Morulae is seen in...
o Klebsiella oxytoca o Anaplasma
• Which virulence factor of E. coli 0157:H7 is a • A macular rash known as Horder spots that
phage-encoded cytotoxin identical to the Shiga toxin resembles the rose spots of typhoid fever is
(Stx) produced by Shigella dysenteriae type I? associated with...
o Verotoxin I o Chlamydophila psittaci
• What is the color of colonies of Burkholdria cepacia • Which of the following C. trachomatis serogroups
in OFPBL agar? requires ulcers as an appropriate specimen
o Yellow o L1
• The following are true about Stenotrophomonas o L2
maltophilia except: o L3
o oxidase-positive • Which of the following serovars are associated with
trachoma?
o Ba
• Sulfa susceptibility: susceptible
o Chlamydia trachomatis
• Grows on sheep blood and chocolate agars.
o M. hominis
• Transport medium for Mycoplasma...
o Shepard’s 10B broth
• Which of the following requires glucose as a major
energy source?
o M. pneumoniae
o M. genitalium