final exam guide Flashcards
1
Q
Bacterial capsules are associated with what property?
A
primary virulence factor
2
Q
what phase of the bacterial growth curve is best for biochemical testing?
A
exponential growth phase
3
Q
what type of environment (aerobic, anaerobic, or microaerophilic) is provided by the candle jar?
A
microaerophilic
4
Q
what is the purpose of the Albert’s stain?
A
used to stain metachromatic granules of corynebacterium diptheriae
5
Q
give an example of a differential, enriched, and selective media
A
enriched = blood agar differential = McConkey selective = MacConkey OR thayer martin
6
Q
what are the standard conditions for the autoclave?
A
15 lbs/square inch
121 degrees
for 15 minutes
7
Q
what is the most abundant organism found in the human intestinal tract?
A
bacteroides
8
Q
what is the most important single test that differentiates staphylococcus aureus from non-pathogenic staphylococci ?
A
coagulase
9
Q
alpha streptococcus viridians are the most important cause of what serious illness?
A
SBE
10
Q
what is the only significant pathogen in the throat?
A
group a beta strep
11
Q
Enterococcus ( which is BEA + and 6.5% NaCl+) belongs to which lancefield group?
A
D
12
Q
foul smelling pus from an abcess which yields gram positive cocci in chains on gram stain would be indicative of what organism?
A
anaerobic strep
13
Q
how do you identify Neisseria Gonorrhoeae?
A
dextrose and oxidase +
gram =
14
Q
how do you identify Neisseria Meningitidis ?
A
gram = oxidase + dextrose and maltose + grows on thayer martin can be normal in throat
15
Q
what three antibiotics are added to Thayer-Martin to make it a selective medium for pathogenic Neisseria?
A
Vancomysin
colistin
nystatin
16
Q
what are the general characteristics of the family Enterobacteriaceae?
A
glucose fermenters
oxidase =
peritrichous flagella
17
Q
what is the appearance of a positive test for citrate?
A
blue color on slant and/or growth
18
Q
what is the appearance of a positive test for indole?
A
red color
19
Q
what is the appearance of a positive test for H2S?
A
black
20
Q
what is the appearance of a positive test for phenylalanine
A
dark green color
21
Q
what is the appearance of a positive test for VP?
A
pink-red color
22
Q
what is the reagent used for the indole test?
A
kova’s reagent
23
Q
what are the reagents used for the nitrate test?
A
sulfanilic acid and alpha-naphthylamine
24
Q
what are the reagents used for the phenylalanine test?
A
10% ferric chloride
25
what are the reagents used for the VP test?
alpha-naphthol
| potassium hydroxide
26
what is the best means to differentiate the genus enterobacter from the genus klebsiella?
motility
27
which genera are urea positive?
proteus
28
LDC differentiates what organism from non-pathogenic H2S producers, such as citrobacter and proteus?
salmonella
29
what is the causative agent of hemorrhagic colitis and hemolytic uremic syndrome due to its production of Verotoxin ( also known as shigella-like toxin)?
e. coli 0157
30
what are the characteristics of serratia marcesens ?
```
chromogenic
antibiotic resistant
associated with UTI
hospital acquired infections
people with wounds who are outside a lot
```
31
what test differentiates proteus mirabilis from proteus vulgaris? (both of which who can swarm on SBA or chocolate agar)
indole
M is =
V is +
32
which genera are phenylalanine positive?
proteus
providencia
morganella
33
which organisms causes an infection of the mesentery suggestive of actue appendicitis?
yersinea
34
K/A with gas and H2S in TSI is suggestive of what intestinal pathogen?
salmonella
35
what non-pathogenic organism is biochemically so similar to shigella that isolates that are biochemically identified as shigella must be typed?
alkalecense dispar
36
what is the difference between a food poisoning and a food infection?
food poisoning - staph aureus , preformed toxins, early on set of symptoms
food infection- salmonella , viable organisms, later onset of symptoms
37
what organism could be described as an oxidase positive glucose-fermenting rod commonly found in water and soil?
aeromonac hydrophilus
38
a gram negative coccobacillus isolated from a cat bike is most likely to be
pasturella multocida
39
a salt-loving organism responsible for gastroenteritis due to contaminated sea food is most likely to be ?
vibrio
40
what media is used to differentiate between oxidation and fermentation?
hugh-leifson
41
a gram negative coccobacillus isolated from a patient with endocarditis that is oxidase + catalase = indole + non-motile and weakly fermentative would most likely be?
cardio bacterium
42
what are the three most commonly isolated non-fermentative bacteria?
pseudomonas aerogenosa, acetobacter, stinotrophomonas
43
a non-fermentor with a blue-green pigment and a grape-like odor is?
pseudomonas aerogonosa
44
a non-fermenter that is a strong maltose oxidizer and a weak glucose oxidizer is?
stinotrophomonas montophilia
45
the causative agent of glanders is?
burholderia (pseudomonas mallie)
46
a gram negative, oxidase negative coccobacillus
bordetella pertussis
47
what genus of bacteria can be confused with neisseria beceause they are oxidase + and sometimes grow on Thayer-Martin and can be differentiated by gram stain since those organisms are gram negative rods rather than cocci?
morexella
48
a yellow pigemented, oxidase + gram negative rod which can cause meningitis (especially in infants) is?
flavobacterium meningosepticum
49
when is it the best time to try to isolate brucella from the bloodstream?
first three weeks
50
Listeria and corynebacterium are best differentiated by what test?
motility
51
what organism is described as a gram + aerobic partially acid-fast rod which usually appears on gram stain as a delicate branching rod?
nocardia
52
why are routine sterile swabs (culturettes) NOT acceptable for anaerobic cultures?
not anaerobic
53
the causative agent of pseudomembranous colitis (PMC) associated with over-treatment with antibiotics is?
clostridium difficile
54
what anaerobic organism usually produces a black colony on laked blood agar?
prevetella melininegenica
55
gram negative, pleomorphic rods which are non-spore forming and are strict anaerobes could be ___________?they are normal inhabitants of the mouth so can be isolated from infections of the nasopharynx, the sinuses, etc.
fusobacterium
56
a gram positive branching rod isolated from "sulfur granules" obtained from a patient's jaw is?
actinomiyces
57
lactobacillus is most frequently isolated from vaginal swabs or?
adult female urines
58
what anaerobic organism is a normal inhabitant of the skin most frequently isolated from 5-7 day old blood cultures where it is a contaminant?
propioni bacterium acnes
59
acid-fast bacillus are usually catalase?
+
60
what substance is the most commonly used agent for concentrating sputums in AFB culture becuase it decontaminates the sputum (removes normal flora organisms) is a mucolytic ( mucuous destroying) agent, and it does not damage the AFB?
N-acetyl-L-cystine
61
an acid fast bacillus (AFB) producing a buff colored, dry heaped up colony that is niacin and nitrate positive is most likely to be ?
mycobacterium tuberculosis
62
which species of organism causes a form of rat bite fever known as Haverhill fever and characteristically produces L-forms?
streptobacillus moniliformis
63
in a sputum culture which reveals large numbers of WBC's on gram stain but no organisms, one would suspect what organism?
legionella pneumophilia
64
what respiratory pathogen is associated with primary atypical pneumonia (Eaton's agent pneumonia) increased cold agglutination titre, and streptococcus MG?
mycoplasma pneumoniae
65
the results of kirby-bauer susceptibility tests are reported as
sensitive, intermediate , or resistant
66
the __________ is defined as the smallest concentration of a drug that completely inhibits growth
MIC
67
for which diseases are blood cultures are the best means of identification?
sepsis, SBE, typhoid fever
68
_______ is often added to blood culture media because it acts as an anticoagulant inactivates teh aminoglycosides and will neutralize the bactericidal effects of human serum
sudium polyanithol sulfonate
69
which serological typing of Hemophilus influenza is the most pathogenic?
type B
70
what organism is enhanced by cold temperatures?
Listeria
71
the toxicity test for crynebacterium diptheriae is called the
elek test
72
what is the test used to identify the alpha toxin of clostridium?
nagler
73
what agar is used in kirby bauer sensitivity test?
mueller hinton
74
what is a castaneda bottle?
blood culture bottler with slant off media, broth
| isolates brucella
75
the bacterial infection which is characterized by donovan bodies is caused by what organism ?
klebsiella granulomatis
76
sulfa drugs
broad spectrum
compete with folic acid
aplastic anemia, granulocytopenia, thrombocytopenia
toxic to kidneys
77
penicillin
gram + organisms
interferes with cell wall synthesis
may produce allergies
78
nonphotochromgens
unpigmented (except light yellow color which is not intensified by light)
79
photochromgens
unpigmented in the dark, but pigmented in the light
80
rapid growers
colonies appear in 3-5 days
81
scotochromogens
pigmented even in the dark
82
mycobacterium kansaii
group 1
nontuberculous mycobacterial pulmonary
photochromogen
83
mycobacterium marinum
group 1
photochromogen
"swimming pool granuloma" a cutaneous infection when traumatized skin comes in contact inadequately chlorinated fresh/salt water
84
M. szulgai
group II
scotochromogens
pulmonary disease similar to TB
85
M. Tuberculosis
group III
| causative agent of tuberculosis
86
a slightly curved gram negative rod
oxidase +
sensitive to naladixic acid
campylobacter fetus s.s. jejni
87
gram + CAMP +
Group B
88
gram + lancet "p"disc
| optochin sensitive
strep pneumoniae
89
gram = rod
oxidase +
blue-green pigment
42 degree tube
pseudomonas aereogenosa
90
gram + pleomorphic rods
| hematin NAD "XV"
hemophilus influenza
91
what agar does bordatella use?
potato-blood-glycerol
92
what agar does C. diptheriae use?
potassium tellurite
93
what agar does francisella use?
cystine-blood-glucose
94
what agar does vibrio use?
thiosulfate-citrate-bile salt- sucrose TCBS
95
what diseases dos bordetella pertusis cause?
whooping cough
96
what disease does brucella cause?
undlent fever
97
what diseases does hemophilus influenza cause?
meningitis
98
what disease does hemophilius bucrydi cause?
chancroid
99
what disease does chlostridium cause?
tetanus (tetani/ lock jaw)
100
what disease does chlostridium perfringence cause?
gang green
101
what disease does corynebacterium cause?
diptheria
102
what disease does listeria cause?
still births
103
what disease does leptospira cause
hemorrhagic jaundice
104
what disease does treponema cardium cause?
penta
105
what disease does Treponema palladium cause?
syphilis
106
what disease does Treponema partenoe cause?
yaws
107
what organism is this nickname used for: friedlanders bacillus
klebsiella pneumoniae
108
what ogniams is this nickname used for: kochweeks bacillus
hemophilus aegypticus
109
what is the nickname for this organism: hemophilus influenzae
pheiffer bacillus
110
what is the nickname for this organism: mycobacteria leprea
(leprosy)
| hansons bacillus
