Final Flashcards
1
Q
If a GNB can only grow on chocolate agar it would be considered fastidious__.
List some of these organisms
A
•Neisseria Gonorrhea
Haemophilus
2
Q
Mac is?
A
Selective and differential
3
Q
MAC that turns pink indicates?
A
Lactose fermentation
4
Q
How do we quantitate CFUs in a urine culture?
A
Count multiplied by 1000.
5
Q
S. aureus morph and bio-chem testing?
A
Smooth, buttery, creamy yellow
Catalase (+)
Coagulation bound & free (+)
6
Q
Size, shape, color, size, growth, surface, margin, elevation and hemolysis characteristics describe?
A
Colonial morph
7
Q
Types of margins?
A
Smooth (Entire)
Rough
Irregular
Curled
Filamentous
Swarming
Star-like (Yeast)
8
Q
Mutation
A
Change in DNA coding for an organism.
9
Q
Where do mutations occur?
A
Cell division
10
Q
Antigen
A
Something from outside/inside, causes body to antibodies.
11
Q
Antibody
A
Produced against antigen.
12
Q
S. pneumo when treated W/ bile?
A
Melts in bile.
13
Q
What is the test on s. Pneumo W/bile?
A
Bile solubility test
14
Q
PMNs or nets in a gram stain are a sign of?
A
Infection
15
Q
Special quality of some bacillus?
A
Spore former (Heat resistant)
16
Q
Camp Test
A
Causes arrowhead, when it touches S. aureus.
17
Q
When an arrowhead reaction is seen, what happens to the hemolysis?
A
Stronger beta hemolysis
18
Q
CAMP positive organisms?
A
GBS A. galactiae
19
Q
Modes of direct transmission?
A
Hand to hand contact
Sex
Congenital
Droplet
20
Q
Modes of indirect transmission?
A
No hand contact: Fomites, water, food, animals, vectors, airborne (Inhalation, aerosols,)
21
Q
IMVC: ++–, glucose +, nitrate +, TDA -, citrate -, H2S-, ONPG +, TSI A/A + gas, LDC +, unease-
A
E. coli
22
Q
DNase +, Lipase +, Gelatine +,
Glucose +, nitrate +, citrate +, LDC +, ODC +, H2S -, Red pigment
A
S. marcescens
23
Q
H2S+, Urease-, Motility+, ONPG+, LDC+, lactose-
A
Salmonella
24
Q
Glucose+, nitrate+, LDC-, Citrate-, H2S-, lactose-, non-motile
A
Shigella
25
H2S+, glucose +, nitrate +, citrate -, indole-
Salmonella typhi
26
Glucose+, nitrate+, TDA+, urease+, H2S+, indole+
Proteus vulgaris
27
Oxidase+, indole+, arginine-, TSI K/A, 6% NaCl growth+, TCBS agar blue-green
Vibrio
Vibrio parahemolyticus
28
Oxidase+, TSI A/A, indole+, arginine+, lysine+, ornithine-
Aeromonas hydrophilia
29
oxidase +, catalase +, urease -, Hippurate hydrolysis +, growth temps 25 – 37 +, nalidixic acid S, cephalothin R, darting motility, microaerophilic
Associated infections: Bacteremia, Endocarditis, meningitis, wound infections, pneumonia.
Multiple ABX resistances
White pinpoint colonies on SBA W/ increased CO2
"Gull-wings"
Campylobacter jejuni
30
glucose +, TDA -, citrate +, LDC +, ODC -, indole -, oxidase -, VP +, mucoid +, motility -, ADH -
Klebsiella pneumoniae
31
oxidase +, oxidizes glucose +, yellow pigment
Chryseobacterium or
Elizabethkingia
32
TCBS agar green colonies, oxidase +, glucose fermentation +, lactose fermentation +, sucrose fermentation -, LDC +, ODC +, ADH -
Vibrio vulnificus
33
oxidase -, TSI A/A, indole -, urease +, ODC +, sucrose +, H2S -, motility
at 25 C +
Yersinia Enterocolitica
34
TSI K/A gas +, H2S +
Salmonella typhimurium
35
violet pigment, almond smell, MAC growth +, growth at 42 C +, oxidase +, glucose fermentation +, indole -
Chromobacterium
36
morph GN coccobacilli, oxidase -, catalase +, nitrate -, ONPG -, LDC -, ODC -
Acineobacter baumannii
37
oxidase W+, TSI K/K, glucose oxidation +, lactose oxidation +, maltose oxidation +, mannitol oxidation +, fluorescence -,
LDC +
Commonly seen in PTs W/ Cystic fibrosis
Burkholderia cepacia
38
glucose +, gas +, indole -, urease +, TDA +, H2S +
Proteus mirabillis
39
green pigments pyocyanin & pyoverdin, grape smell, ADH +, LDC -, ODC +, most isolated non-fermenter, alginate capsule, oxidase +, nitrate +,
70-80% of all isolated
non-fermenters, found t/o environment & nature?
Pseudomonas aeruginosa
40
Pyocyanin Pigment?
blue pigment that is soluble in water and choloroform.
41
Pyoverdin pigment?
Yellow- yellow/green fluorescent pigment.
42
Pseudomonas aeruginosa is intrinsically resistant to?
Penicillin
Ampicillin
1st & 2nd gen cephalosporins
Trimethoprim
Chloramphenicol
Tetracyclines
43
What acquired resistance can P. aeruginosa gain, especially as an HAI?
Aminoglycosides (Tobra, gent, amikacin)
Beta-lactams
Carbapenems
44
Non-motile, weakly oxidase positive, only non-motile pseudomonad, possible bioterrorism, on SBA smooth cream-white colonies, "Glanders"
Burkholderia mallei
45
abundant H2S + motility, gas +, indole +
Edwarsiella spp
46
Endogenous infection
Something of normal flora, traumatically introduced to sterile site.
47
Nosocomial infections
HAIs (MRSA)
48
Community acquired infections?
Normal everyday environment, associated W/ the patient (GBS).
49
What is our primary stool pathogen?
Toxigenic E. coli (0157, ETEC, EHEC)
50
Most common primary stool pathogens?
Shigella and Salmonella
51
Other common stool pathogens?
Yersinia and Campylobacter
52
What agars can be used to isolate stool pathogens?
XLD
HE
SS
EMB
Campy plates
53
What are peak levels?
Highest level of antibodies in the body, any higher could kill someone.
54
What is a trough level?
Lowest level of antibodies in the body, any lower would allow microbial growth.
55
When are trough levels drawn?
Just before next dose.
56
What is the range between peak and trough levels?
Therapeutic range
57
What are some medications that have peak and trough levels drawn?
Vancomycin
Gentamycin
Amikacin
Tobramycin
58
Define fermentation?
The chemical breakdown of an organic compound.
59
What is the product of fermentation?
Acid
60
Types of immunity?
Humoral- Adaptive
Innate-Inborn
61
Characteristics of GN cell walls?
Thinner layer of peptidoglycan
Outer membrane of lipopolysaccharide.
62
Characteristics of GP cell walls?
Thick peptidoglycan
Allows them to hold crystal violet (W/ mordant- Iodine)
Teichoic acid
63
Pseudomonadaceae was first isolated from?
Soldier's wounds oozing a green exudate.
64
Describe the Proteus genus?
UTIs of the urinary tract
Swarming motility on SBA
Wound Infections
Soil, water, or fecal-contaminated materials
Not mucoid
65
Labelled Immunoassays?
Immuno-fluorescent testing, used in Legionella or Bortella diseases.
66
Types of labeled immunoassays?
Antibody labelled for antigen assay (Direct)
Antibody labelled for antibody assay (Indirect)
Antigen labelled for antibody assay.
67
AB labelled for antigen assay?
Direct fluorescent assay (DFA)
68
Antibody labelled for antibody assay?
Indirect fluorescent assay (DFA)
69
EIA?
Enzyme-linked Immunosorbent Assay (ELISA), also called Enzyme Immunoassay (EIA).
70
EIA's clinical applications?
Antigens of: Giardia, Cryptosporidium, viral antigens.
Antibodies of: Legionella, mycoplasma, Borrelia burgdorferi (Lyme disease), viruses.
71
What is used to detect Chlamydia and N. gonorrhoeae?
PCR testing
72
Are EIAs qualitative or quantitative?
Both
73
Bacterial modes of resistance to antimicrobial agents?
Efflux
Modification to targe site for antibodies.
Decreasing cell wall permeability.
Enzymatic (B-lactam)
Alterations of the porin.
74
What is the complement complex?
20 different proteins that are reactive for inflammation.
75
What is the latex agglutination test?
testing for the antibody-antigen complex, creates particulates in the sample.
76
Why is latex used in the agglutination test?
It is a detector W/ multiple active sites and it is bio chemically inert.
77
What is an organism positive on the latex agglutination test?
S. aureus
78
What is the microscopic arrangement of micrococcus?
GP clusters
79
Microscopic arrangement of streptococcus?
GP chains
80
Neisseria's arrangement?
GN diplococci in pairs
81
GPB W/ terminal spores?
Clostridium
82
Spore forming GNB?
B. Cereus
B. anthracis
83
Non-spore forming GNB
Non-branching
Catalase (+)
Non-acid fast
L or V shapes
Club-shaped
SBA or Chocolate
Corynebacterium
84
Bench tests?
Catalase
Oxidase
Coagulase
Urease
Indole
PYR
Hippurate Hydrolysis
Beta-Lactamase
85
Antigen
Foreign compounds that stim an immune response.
86
Antibodies
Proteins formed in response to stimulation from antigens.
87
Affinity
strength of the reaction
88
Avidity
strength of the bond
89
Epitope
part of the antibody that reacts W/ antigen (antigenic determinant.
90
Specificity
ability of an antibody to distinguish between Antigens, that have very small differences.
(Like what they like)
91
Cross-reactivity
antibody that is specific for 1 antigen reacts W/ another antigen W/ similar structure.
92
Sensitivity
ability to detect small amounts of antigen or antibody.
93
What does the Cefinase antibody susceptibility test for?
Beta-lactamase resistance
94
Cefoxitin disk diffusion screen test for?
Methicillin resistance s. aureus
95
What test is used for penicillin resistance in S. pneumoniae?
Oxacillin test
96
Acquired resistance means?
Gained from another bacteria, via plasmid transfer.
97
Intrinsic resistance means?
Inborn resistance
98
What do bacteria use to move?
Flagella
99
What part of a bacteria makes it antiphagocytic?
The capsule
100
Lipopolysaccharide membrane helps W/?
Attachment
101
Barlett's classification indicates what?
Inflammation
102
What does Bartlett's classification compare?
Neuts in sputum to epi cells.
103
Scoring system for Neuts per low power field?
< 10 = 0
10-25= +1
> 25 = +2
Mucus= +1
104
Scoring system for Epi cells per low-power field?
10-25 = -1
> 25 = -2
105
Scores of what indicate a lack of inflammation or presence of saliva?
0
106
An endogenous infection commonly caused by E. coli?
UTIs
107
In nucleic acid testing, what does target mean?
Sequence of interest in suspected organism.
108
What is a probe in nucleic acid testing?
fully ID a specimen.
109
Bacteremia
bacteria in the blood
110
Septicemia
inflammation response to bacteria in the blood.
111
Septic shock
Organ shut down
112
What part of S. pyogenes cause necrotizing fasciitis?
Pyogenic Exo-toxin
113
H. influenzae growth requirements?
Requires X and V factors
Beta-hemolytic on rabbit blood agar ( - ).
114
H. parainfluenzae growth requirements?
Requires V factor
115
H. haemolyticus growth requirements?
Requires X and V factors
Beta-hemolytic on rabbit blood agar (+)
116
H. parahaemolyticus growth requirements?
Requires V factor
Beta-hemolytic on rabbit blood agar (+)
117
N. gonorrhoeae produces infections where?
Children during birth (Eyes)
(Ophthalmia Neonatorum)
Gonorrhoeae of the knees
STDs
118
How can we biochemically ID S. agalactiae?
Bacitracin test (R)
PYR (+)
Camp factor (+)
119
All Enterobacteriaceae are negative for?
Oxidase
120
What is the only enterobacteriacea, that is oxidase negative?
Plesiomonas
121
How can Legionella spread?
Potable water
A/C
122
What is listeriosis?
ingested contaminated foods (meats, dairy, veggies, fruits)
Causes: meningitis, conjunctivitis, endocarditis, septicemia
123
Listeria monocytogenes
Tiny, GP diphtheroid
124
Catalase positive
Oxidase negative
H2S negative
Tumbling motility
Bile esculin positive
CAMP: Rectangle with beta-hemolytic S. aureus
Can survive refrigerator temperatures
Listeria monocytogenes
125
Non-Spore forming
GPB
Non-branching
Catalase ( - )
Normal mouth flora
Produce large amounts of lactic acid.
Tolerates acidic pH of 3-4
Lactobacillus acidophilus
126
Bacterial Vaginosis
Pleomorphic
Gram variable- GPB
Fastidious
Grows on SBA, Chocolate
Loves human blood agar
Clue cells
Gardnerella vaginalis
127
Branching filaments that fragment into rods and cocci.
Slow growers
Variable colonial morph
Found in soil and water
N. asteroids
128
Virulence factors of S. aureus?
Protein A- inhibits complement fixation
Capsular polysaccharide- antiphagocytic
Peptidoglycan and teichoic acid- attach to mucous membranes and sustain environmental stresses.
Penicillin binding protein (2)
129
S. aureus extracellular toxins?
Hemolysin
Clumping factor
Staphylocoagulase
Staphylokinase- Fibrinolysin (Infection spreader)
130
S. aureus enzymes and exotoxins?
Lipase- hydrolyze lipids
Exfoliative A & B toxins- hydrolyze tissue
Hyaluronidase- lyses hyaluronic acid in connective tissue
Leukocidin- toxic to neuts and macros
131
Superantigens
Includes enterotoxins and other pyogenic toxins that promote cytokine release and progression of toxic shock syndrome.
132
Superantigen example?
Toxic-shock syndrome toxin (TSST-1)
133
How are shigella and klebsiella similar?
Non-motile
134
E. coli's appearance on MAC plates?
Pink because it's a lactose fermenter
135
E. coli on EMB plates?
Ferment lactose and turn agar green.
136
How is Y. pestis spread (plague)?
Rats and rat fleas
137
GN straight/curved bacilli
Facultative Anaerobe
Oxidase (+)
Catalase (+)
Ferments carbs
Vibrio
138
Classic strain Non-hemolytic
El tor strain Beta-hemolytic
Can have choleragen toxin (CT)
Ferment glucose and sucrose
Indole (+)
LDC (+)
ODC (+)
ADH ( - )
String test (+)
Vibrio cholerae
139
Nonhemolytic on sheep blood agar
TCBS: Green colonies
Ferments glucose
Halophilic (will not grow in nutrient broth without NaCl)
Oxidase and indole positive
LDC and ODC positive
ADH negative
Vibrio spp
Vibrio parahaemolyticus
140
TCBS Green colonies
Ferments glucose and LACTOSE
Halophilic
Oxidase and indole positive
LDC and ODC positive
ADH negative
Vibrio vulnificus
141
Curved GNB
Motile
Polar glaellum
Microaerophilic
Capnophilic
Oxidase (+)
Non-saccharolytic
Very low infectious load
Campylobacteraceae
142
Enteric Campylobacters?
C. jejuni
C. coli
143
Most infectious campylo
Curved bacilli (may appear S-shaped)
Growth @ 42 degrees (slow @ 37)
Catalase and oxidase (+)
No carb oxidation/ferment
Cephalothin (R)
Nalidixic acid (S)
Campylobacter jejuni
144
How do we differentiate C. jejuni and c. coli, when all the tests are the same?
Nalidixic acid or cephalothin testing
145
Rare cause of extraintestinal infections.
Febrile systemic disease
Does not grow @ 42 degrees
Similar bio-chemically to C. jejuni and C. coli
C. fetus
146
Helicobacter
Stomach is the natural habitat
Strong urease (+)
Motile W/ 4-6 polar flagella
Oxidase (+)
Microaerophilic
Curved GNB U shape
Hippurate ( - )
H. pylori
147
How can we non-invasively confirm Hl pylori?
Urease breath test
148
Shigella and salmonella differentiate from other enterobacteriaceae on HE and XLD?
Non-lactose fermenter
149
How can you differentiate Acinetobacter and Neisseria?
Neisseria is oxidase (+)
150
Lancefield Group A?
Strep throat
Pyoderma
Streptococcal toxic shock syndrome
Necrotizing fasciitis
151
Lancefield Group B?
Neonatal bacteremia
Pneumonia
Meningitis
152
Lancefield Group D
UTIs
Intra-abdominal infections
Endocarditis
VRE
153
Lancefield Group F?
Wound infections
154
What type of infections does Pasteurella cause?
Wound infections
155
Early sign of Lyme disease?
Erythema migrans rash (bull's eye)
156
What is the RPR test?
Rapid plasma reagin
Syphilis, caused by Treponema pallidum
157
Anthrax types?
Cutaneous
Inhalation (pulmonary)
Gastrointestinal/Oropharyngeal
Injectional
158
Inhibits GPC W/ Vancomycin
Inhibits GNB W/ Colistin
Modified Thayer-Martin Agar
(MTM)
159
Veterinary pathogen
Contaminated milk or infected livestock
Rare lymphadenitis
C. pseudotuberculosis
160
How can S. lugdunensis be mistaken for S. aureus?
It is bound coagulase (+)
S. aureus is bound and free coagulase (+)
161
Shiga- toxin producer
Most common serotype is 0157:H7
Bloody diarrhea
Enterohemorrhagic E. coli (EHEC)
162
How are the ABXs related?
Penicillin, Cephalosporins, Vancomycin
Cell wall synthesis inhibitors
163
What does tetracycline, erythromycin, and chloramphenicol ABXs have in common?
Protein synthesis inhibitors
164
Sulfonamide ABXs work by?
Producing antimetabolites or are antimetabolites
165
All staph organisms grow on what?
MSA
166
Virulence factors of GAS?
Streptococcal pyogenic exotoxins or superantigens
Streptolysin O- lyses blood cells, oxygen liable, very immunogenic.
Streptolysin S- lyses RBCs and PLTs.
Streptokinase- fibrinolysin
M (emm) protein-antiphagocytic
167
Bile esculin (+)
6.5% NaCl broth (+)
PYR ( - )
Penicillin (R)
Enterococcus
168
The EM rash (Bull's eye) is diagnostic for what?
Lyme disease
169
Borrelia recurrenitis is the etiologic agent for what?
Relapsing fever
