TEST BANK For Textbook of Diagnostic Microbiology,
6th Edition By Connie Mahon
Types of susceptibility testing? - ANSWER:Kirby-Bauer
E-Test
Schlichter Test
Automated Systems
Why perform susceptibility testing? - ANSWER:Help infected patients-aid in tailoring
treatment.
Help future patients
Help patients moving forward.
Side effects/Toxicity of Antibiotics? - ANSWER:Mild-Severe
Mild- nausea
Severe-nephrotoxicity, bone marrow toxicity, allergic reactions
Inhibitors of other metabolic processes - ANSWER:Sulfonamides-competitive
inhibition of folic acid synthesis; broad spectrum; UTI (folic acid pathway for bacteria
produces precursors needed for DNA synthesis)
Trimethoprim-frequently combined with sulfonamides
Nitrofurantoin-mechanism unknown; UTIs only
Agar used for Kirby-Bauer Disk Diffusion
Susceptibility and why? - ANSWER:-Mueller-Hinton-well defined chemical
composition constant and reproducible
-supports growth of most frequent isolates
-buffered to prevent pH change
-doesn't interfere with antibiotic activity
Microbial Mediated Resistance:Acquired - ANSWER:Acquired resistance:change in
genetic composition
-genetic mutation
-gene transfer from one organism to another
-combination of the above
unpredictable
heteroresistance
Heterorestance - ANSWER:resistance to certain antibiotics expressed by a subset of a
microbial population that is generally considered to be susceptible to these
antibiotics according to traditional in-virto susceptibility testing
Enzymes that contribute to Beta-Lactam resistance - ANSWER:Penicillinases
Cephalosporinases
ESBL's
Cephamycinases
,Carbapenemases
Extended Spectrum Beta-Lactamases
(ESBL's) - ANSWER:enzymes that mediate resistance to extended spectrum
cephalosporins(4th and 5th generation)
and monobactams,but do not affect carbapenems or cephamycins.
Derived from Gram- rods(Enterobacteriaceae)
D-Test - ANSWER:Tests for the presence of macrolide-inducible
resistance to clindamycin produced by a reducible methyl's that altars the common
ribosomal binding site for macrolides.
Carbapenem Resistant Enterobacteriaceae
(CRE) - ANSWER:contain enzymes that break down carbapenems.
E. coli, Klebsiella pneumoniae
Where is the site of the gas exchange? - ANSWER:Alveoli
What is quorum sensing? - ANSWER:Using chemical messengers to allow for the
detection of other bacteria in proximity to work together to achieve a task that
cannot be accomplished by a single bacterium on its own
VISA and VRSA
Vancomycin Intermediate/Resistant
Staph. aureus - ANSWER:VRSA emerged from the exchange of genetic material from
vancomycin resistant enterococci to MRSA.
Resistance to Vancomycin is.... - ANSWER:...the result of altered cell wall precursors
that reduces the antibiotics ability to bind to the microbe.
Type I and II Pneumocystis - ANSWER:Type I- flat, plate-like cells cover majority of
alveolar surface
Thin structure allows for the gas exchange between alveoli and capillaries
Type II- Larger Cuboidal Epithelium
Secrete surfactant-a fluid that creates a film maintaining surface tension and
prevents alveolar collapse
The transmission of Aeromonas to humans is via... - ANSWER:...ingestion of
contaminated seafood and water.
Cholera Toxin - ANSWER:Which substance causes profuse, watery diarrhea leading
to dramatic fluid loss, severe dehydration, and hypotension that frequently leads to
death
Primary drug of choice for Stenotrophomonas
maltophilia is... - ANSWER:trimethoprim-sulfamethoxazole
, Plump, GNB that occur in pairs and can be mistaken for Neisseria app is which
organism? - ANSWER:Acinetobacter
Which organism produces exotoxin A and several other proteolytic enzymes? -
ANSWER:Pseudomonas aeruginosa
Yellow-pigmented organism with gliding motility that grow in increased CO2, but not
in ambient air is...... - ANSWER:Capnocytophaga
Bacteremia caused by Pseudomonas aeruginosa in immunocompromised can invade
subcutaneous blood vessels and result in the formation of cutaneous papillose that
become black and necrotic - ANSWER:Ecthyma gangrenosum
Mechanism of acquired, high-level resistance to vancomycin involves..... -
ANSWER:production of altered cell wall precursors that do not bind to the antibiotic
with a strong avidity
OFPBL media is one of the best media to isolate which organism from the sputa of CF
patients? - ANSWER:Burkholderia cepacia
OFPBL - ANSWER:Oxidation Fermentation Polymyxin Bacitracin Lactose Agar
Medical Devices - ANSWER:A good source for Burkholderia cepacia
Pneumonia
Signs/Symptoms and Diagnosis - ANSWER:Fever, chills, cough, dyspnea
infiltrate in lung X-Ray, sputum cultures, Pulse Oximetry, Blood tests.
What is Cystic Fibrosis? - ANSWER:autosomal recessive inheritance pattern
problem with the Cystic Fibrosis Transmembrane Regulator (CFTR)
build up of mucous-repeat infections
What does the CFTR do? - ANSWER:moves cl- ions
reabsorbs cl- in sweat glands
secretes cl- into lumen of digestive and resp. tract
A convenient ID scheme for Pseudomonas aeruginosa - ANSWER:oxidase+, growth at
42 degrees Celcius on MH agar with blue/green or red/brown colonies
TSI: K/K gas- H2S-
Etiology of Pneumonia - ANSWER:Bacteria
Viruses
Fungal
Clinical Classifications of Pneumonia - ANSWER:Community Acquired
Hospital Acquired
6th Edition By Connie Mahon
Types of susceptibility testing? - ANSWER:Kirby-Bauer
E-Test
Schlichter Test
Automated Systems
Why perform susceptibility testing? - ANSWER:Help infected patients-aid in tailoring
treatment.
Help future patients
Help patients moving forward.
Side effects/Toxicity of Antibiotics? - ANSWER:Mild-Severe
Mild- nausea
Severe-nephrotoxicity, bone marrow toxicity, allergic reactions
Inhibitors of other metabolic processes - ANSWER:Sulfonamides-competitive
inhibition of folic acid synthesis; broad spectrum; UTI (folic acid pathway for bacteria
produces precursors needed for DNA synthesis)
Trimethoprim-frequently combined with sulfonamides
Nitrofurantoin-mechanism unknown; UTIs only
Agar used for Kirby-Bauer Disk Diffusion
Susceptibility and why? - ANSWER:-Mueller-Hinton-well defined chemical
composition constant and reproducible
-supports growth of most frequent isolates
-buffered to prevent pH change
-doesn't interfere with antibiotic activity
Microbial Mediated Resistance:Acquired - ANSWER:Acquired resistance:change in
genetic composition
-genetic mutation
-gene transfer from one organism to another
-combination of the above
unpredictable
heteroresistance
Heterorestance - ANSWER:resistance to certain antibiotics expressed by a subset of a
microbial population that is generally considered to be susceptible to these
antibiotics according to traditional in-virto susceptibility testing
Enzymes that contribute to Beta-Lactam resistance - ANSWER:Penicillinases
Cephalosporinases
ESBL's
Cephamycinases
,Carbapenemases
Extended Spectrum Beta-Lactamases
(ESBL's) - ANSWER:enzymes that mediate resistance to extended spectrum
cephalosporins(4th and 5th generation)
and monobactams,but do not affect carbapenems or cephamycins.
Derived from Gram- rods(Enterobacteriaceae)
D-Test - ANSWER:Tests for the presence of macrolide-inducible
resistance to clindamycin produced by a reducible methyl's that altars the common
ribosomal binding site for macrolides.
Carbapenem Resistant Enterobacteriaceae
(CRE) - ANSWER:contain enzymes that break down carbapenems.
E. coli, Klebsiella pneumoniae
Where is the site of the gas exchange? - ANSWER:Alveoli
What is quorum sensing? - ANSWER:Using chemical messengers to allow for the
detection of other bacteria in proximity to work together to achieve a task that
cannot be accomplished by a single bacterium on its own
VISA and VRSA
Vancomycin Intermediate/Resistant
Staph. aureus - ANSWER:VRSA emerged from the exchange of genetic material from
vancomycin resistant enterococci to MRSA.
Resistance to Vancomycin is.... - ANSWER:...the result of altered cell wall precursors
that reduces the antibiotics ability to bind to the microbe.
Type I and II Pneumocystis - ANSWER:Type I- flat, plate-like cells cover majority of
alveolar surface
Thin structure allows for the gas exchange between alveoli and capillaries
Type II- Larger Cuboidal Epithelium
Secrete surfactant-a fluid that creates a film maintaining surface tension and
prevents alveolar collapse
The transmission of Aeromonas to humans is via... - ANSWER:...ingestion of
contaminated seafood and water.
Cholera Toxin - ANSWER:Which substance causes profuse, watery diarrhea leading
to dramatic fluid loss, severe dehydration, and hypotension that frequently leads to
death
Primary drug of choice for Stenotrophomonas
maltophilia is... - ANSWER:trimethoprim-sulfamethoxazole
, Plump, GNB that occur in pairs and can be mistaken for Neisseria app is which
organism? - ANSWER:Acinetobacter
Which organism produces exotoxin A and several other proteolytic enzymes? -
ANSWER:Pseudomonas aeruginosa
Yellow-pigmented organism with gliding motility that grow in increased CO2, but not
in ambient air is...... - ANSWER:Capnocytophaga
Bacteremia caused by Pseudomonas aeruginosa in immunocompromised can invade
subcutaneous blood vessels and result in the formation of cutaneous papillose that
become black and necrotic - ANSWER:Ecthyma gangrenosum
Mechanism of acquired, high-level resistance to vancomycin involves..... -
ANSWER:production of altered cell wall precursors that do not bind to the antibiotic
with a strong avidity
OFPBL media is one of the best media to isolate which organism from the sputa of CF
patients? - ANSWER:Burkholderia cepacia
OFPBL - ANSWER:Oxidation Fermentation Polymyxin Bacitracin Lactose Agar
Medical Devices - ANSWER:A good source for Burkholderia cepacia
Pneumonia
Signs/Symptoms and Diagnosis - ANSWER:Fever, chills, cough, dyspnea
infiltrate in lung X-Ray, sputum cultures, Pulse Oximetry, Blood tests.
What is Cystic Fibrosis? - ANSWER:autosomal recessive inheritance pattern
problem with the Cystic Fibrosis Transmembrane Regulator (CFTR)
build up of mucous-repeat infections
What does the CFTR do? - ANSWER:moves cl- ions
reabsorbs cl- in sweat glands
secretes cl- into lumen of digestive and resp. tract
A convenient ID scheme for Pseudomonas aeruginosa - ANSWER:oxidase+, growth at
42 degrees Celcius on MH agar with blue/green or red/brown colonies
TSI: K/K gas- H2S-
Etiology of Pneumonia - ANSWER:Bacteria
Viruses
Fungal
Clinical Classifications of Pneumonia - ANSWER:Community Acquired
Hospital Acquired
