Kozel > 2nd Tier Pathogens Flashcards
(138 cards)
1
Q
what shape is pneumococcus?
A
lancet/ovoid
2
Q
is pneumococcus encapsulated?
A
YES
3
Q
older cultures of pneumococcus undergo ________ because why?
A
autolysis
autolytic enzymes are activated by surfactants (bile, detergents)
4
Q
what conversion happens in pneumococcus?
A
rough-to-smooth conversion by transformation
5
Q
what do you grow pneumococcus on?
A
blood agar
6
Q
what is the major antigen of pneumococcus?
A
capsular polysaccharide
7
Q
how many serological types of capsular polysaccharide does pneumococcus have?
A
over 90
8
Q
is the capsular polysaccharide of pneumococcus essential for virulence?
A
YES
9
Q
what is the quellung reaction?
A
incubation of encapsulated bacteria w/ ab makes the capsule refractile
10
Q
is pneumococcus quellung positive?
A
YES
11
Q
what is C polysaccharide?
A
aka teichoic acid
cell wall carb that reacts w/ acute phase protein (CRP)
12
Q
what are the 5 pneumococcal infections?
A
pneumonia sinusitis otitis media meningitis OTHER > peritonitis, endocarditis, arthritis
13
Q
pneumococcal pneumonia makes up what % of bacterial pneumonia?
A
80-90%
14
Q
where is pneumococcal pneumonia in the lung?
A
usu lobar
15
Q
what is the most common cause of otitis media in children >3 mo?
A
pneumococcus
16
Q
pneumococcus causes meningitis in what age groups?
A
young & elderly
17
Q
what 4 things characterize pneumococcal disease?
A
- abrupt onset
- toxicity
- fulminant course
- DIC
18
Q
what causes disease in pneumococcal infections?
A
inflammatory response to bacterium & its pdts
19
Q
what is the trick for pneumococcus to be infectious?
A
produce an inflammatory response but not be killed by it
20
Q
what are the 3 virulence factors for strep pneumo?
A
polysaccharide capsule
pneumolysin
peptidoglycan & lipoteichoic acid
21
Q
what virulence factor of strep pneumo is essential for virulence?
A
polysaccharide capsule
22
Q
what fxn does the polysaccharide capsule serve?
A
prevents phagocytosis
23
Q
what does anticapsular ab do?
A
protects by opsonization
24
Q
what is pneumolysin?
A
a porin
similar to streptolysin O
25
what does pneumolysin do?
contributes to inflammation
| multiple effects
26
where are peptidoglycan & lipoteichoic acid found?
cell wall
27
what do peptidoglycan & lipoteichoic acid do?
activate the alternative pathway
elicit production of IL-1 & TNF-alpha
inflammatory response
28
what virulence factor of strep pneumo is largely responsible for the inflammatory response?
peptidoglycan & lipoteichoic acid
29
is natural resistance to strep pneumo high or low?
VERY HIGH!
30
what % of people carry pneumococci around in their nasopharynx?
40-70%
31
what are the 4 natural defensive barriers that people have against pneumococcus?
cough & epiglottal reflex
mucus & cilia
phagocytosis by alveolar macrophages
splenic clearance from blood
32
what is the most important condition altering resistance to pneumococcus?
sickle cell disease
33
what are the things that can lead to a depressed epiglottal reflex?
alcohol
morphine
anesthesia
34
what can lead to depressed action of cilia?
viral infection like influenza
35
what can happen if a pt has hyposplenia or asplenia?
decreased clearance from blood
36
what 5 things can alter resistance to pneumococcus?
```
depressed cilia action
depressed epiglottal reflex
hypo/asplenia
malnutrition
SICKLE CELL DISEASE
```
37
what are the sx of pneumococcal pneumonia?
```
sudden onset
shaking chill
fever
sharp pleural pain
bloody rusty sputum
```
38
where does pneumococcal pneumonia localize?
lower lobes
| lobar pneumonia
39
what is pneumonic crisis?
occurred in pre-abx era
| dramatic recovery 5-10 days after initial chill
40
how do you isolate pneumococcus (like what do you grow it on)?
blood agar
41
how do you differentiate strep pneumo from strep viridans?
pneumo is...
alpha hemolytic
optochin sensitive
bile soluble
42
what does interpretation of pneumococcal lab diagnosis depend on?
clinical picture
| source of specimen
43
what serological test can you do for pneumococcus?
test for FREE AG in bodily fluids > pneumococcal C polysaccharide
44
how does pneumococcus enter a person?
upper respiratory tract
45
T/F: most pneumococcal infections are endogenous
true
46
what is the incidence of pneumococcus assoc w/?
predisposing factors
47
do most adults have the capsular ab for pneumococcus?
NO
| you have it for N meningitidis & Hib
48
what are the 3 things important for prevention & control of pneumococcus?
prevent primary damage
immunize
isolate to prevent transmission to at-risk pts
49
what is PPSV23?
pneumovax
pnu-imune
purified polysaccharide vaccine
50
how many serotypes does PPSV23 cover?
23
51
what % of bacteremic cases does PPSV23 cover?
94%
52
what is the composition of PPSV23?
purified capsular polysaccharide
53
what is the action of PPSV23?
induction of opsonic ab
54
what is the efficacy of PPSV23?
60-80%
55
how long do PPSV23 titers persist?
at least 5 years
56
is there a booster effect w/ PPSV23?
no
| little to no booster effect
57
for whom is the T-independent ag effective?
>2yo pts
58
who should get PPSV23?
all adults over 65 yo in series w/ PCV13
| anyone 6-18yo w/ specific risk factors
59
what is the composition of PCV13?
polysaccharide protein conjugate
60
what is prevnar 13?
PCV13
| polysaccharide protein conjucate vaccine
61
how many serotypes does prevnar cover?
13
62
how many serotypes does pneumovax cover?
23
63
what % of bacteremic cases does PCV13 cover?
>80%
64
what % of acute otitis media among kids <6yo does PCV13 cover?
65%
65
does PCV13 have T-dependent ag?
yes
66
who should get PCV13?
all children 2-59mo
65yo+ in series w/ PPSV23
at risk kids 6-18yo
67
what is the point of PCV13?
reduce carriage
| produce herd immunity
68
what are the 2 drugs of choice for pneumococcus IF SUSCEPTIBLE?
penicillin
| ceftriaxone
69
T/F: there are increasing reports of abx-resistant pneumococcus
TRUE
| as high as 35% in some regions
70
what is the resistance mechanism of pneumococcus?
acquisition of PBP w/ reduced affinity for abx
71
what are alternative meds for pneumococcus?
vancomycin
macrolides
doxycycline
quinolone
72
what shape is staph aureus?
cocci in clusters
73
what is on the surface of staph aureus?
protein A
74
what is the only catalase positive, coagulase positive bacterium?
staph aureus
75
what are the virulence factors for staph aureus?
adhesive & antiphagocytic factors, toxins, & enzymes
76
what is MRSA?
methicillin resistant staph aureus
77
what is the mutation in MRSA?
altered PBP (PBP2') encoded by mecA gene
78
what are the toxin-mediated staph aureus diseases?
food poisoning
TSS
scalded skin syndrome
79
what are the suppurative infections of staph aureus?
```
impetigo
folliculitis
furuncles/boils
carbuncles
bacteremia
endocarditis
osteomyelitis
septic arthritis
pneumonia & empyema
brain abscess
```
80
what shape is bacillus anthracis?
rod
81
what does bacillus anthracis form?
spores
82
what is the capsular polypeptide of bacillus anthracis?
poly-glutamic acid
83
what is the fxn of poly-glutamic acid?
antiphagocytic
84
what are the 3 exotoxins of bacillus anthracis?
PA > protective ag
EF > edema factor
LF > lethal factor
85
what is the treatment for bacillus anthracis?
ciprofloxacin
86
what does cutaneous anthrax look like?
black eschar formation
87
what does GI anthrax look like?
ulcers at site of invasion
88
what does the clinical course of inhalational anthrax look like?
non-specific signs then severe sepsis
89
which form of anthrax is a biothreat?
inhalational
90
what color is pseudomonas aeruginosa?
green!
| aerugula
91
what shape is pseudomonas aeruginosa?
rod
92
T/F: pseudomonas aeruginosa is nosocomial
TRUE
93
what bacterium is the mucoid polysaccharide capsule assoc w/?
pseudomonas aeruginosa
94
T/F: pseudomonas aeruginosa is highly abx-resistant
TRUE
| requires abx combos!
95
what 5 diseases does pseudomonas aeruginosa cause?
```
pulmonary infection
burn wound infection
UTI
otitis externa
bacteremia
```
96
what does pseudomonas aeruginosa infect to cause UTI?
long-term indwelling catheters
97
what are the strains of pulmonary infection caused by pseudomonas aeruginosa?
mucoid
98
how does pseudomonas aeruginosa cause bacteremia?
opportunistic infection (e.g. neutropenia)
99
what shape is burkholderia?
rod
100
what 3 species of burkholderia do you need to know?
cepacia
pseudomallei
mallei
101
what does B. cepacia cause?
pulmonary infection in pts w/ underlying lung disease (CF)
102
what does B. pseudomallei cause?
melioidosis
103
where does melioidosis occur?
environmental sites in Thailand & N. Australia
104
what is melioidosis clinically?
pulmonary infection & sepsis
105
T/F: melioidosis is a biothreat
true
106
what does B. mallei cause?
glanders in horses
107
T/F: B. mallei & B. pseudomallei are both biothreats
true
108
what shape is acinetobacter baumanii?
coccobacillus
109
acinetobacter baumanii is a ubiquitous ______ in many environments
saprophyte
110
T/F: acinetobacter baumanii is nosocomial & abx- resistant
TRUE
111
is acinetobacter baumanii opportunistic?
yes
112
what disease does acinetobacter baumanii cause in ICUs?
ventilator-assoc pneumonia
113
what does acinetobacter baumanii do w/ wounds?
infects them, esp on battlefield or w/ repeated exposure to diff medical environments
114
what shape is H. influenzae?
coccobacilli
115
what are the nutritional requirements for H. influenzae?
```
factor X (hemin)
factor V (NAD)
```
116
what type of H. influenzae is most important?
type b
117
is Hib encapsulated?
yep
118
what is the Hib vaccine?
protein conjugate of type b polysaccharide
119
what 3 (kind of 4) diseases does Hib cause?
meningitis
epiglottitis
acute & chronic otitis media & sinusitis
120
who gets Hib meningitis?
unimmunized kids
121
is epiglottitis life-threatening?
yep
122
T/F: the strains of h. influenzae that cause sinusitis & otitis media are nontypeable
true
| e.g. they are acapsular
123
what are the 2 most common causes of otitis media & sinusitis?
strep pneumo
| h. flu
124
what does franciscella tularensis require for growth?
cysteine! it's special & dangerous!
125
T/F: franciscella tularensis is facultatively intracellular
TRUE
126
what animal primarily gets franciscella tularensis?
rabbits
127
what are the insect vectors for franciscella tularensis?
hard ticks & biting flies
128
what disease does franciscella tularensis cause?
tularemia
129
what is the most common form of tularemia?
ulceroglandular
130
what does ulceroglandular tularemia follow?
insect bite or direct inoculation
131
what causes oculoglandular tularemia?
inoculation of eye (rubbing)
132
what causes pneumonic tularemia?
inhalation
| biothreat!
133
what is psittacosis?
parrot fever
134
what causes psittacosis?
chlamydophila psittaci
135
what are the clinical manifestations of psittacosis?
respiratory infection
| spread to reticuloendothelial (RES) cells of liver & spleen
136
what is the natural reservoir for psittacosis?
birds
137
what does chlamydophila pneumoniae cause?
respiratory infection > sinusitis, pharyngitis, pneumonia
| possibly atherosclerosis
138
what shape is chlamydophila?
rod or coccoid
