Test 1: lecture 4 gram + Flashcards
1
Q
what are the three main types of gram positive cocci
A
staphylococcus
streptococcus
enterococcus (formerly group D strep)
2
Q
what does staphylococcus look like under the microscope
A
purple cocci in clusters
3
Q
what does streptococcus look like under the microscope
A
purple cocci in chains
4
Q
what does enterococcus look like under the microscope
A
oblong cocci to coccobacilli
often in pairs or chains
5
Q
catalase test can be used the tell the difference between what gram + cocci?
A
staphylococcus → +
streptococcus → negative
enterococcus → negative/ pseudocatalase
6
Q
which gram + cocci will sometimes have positive coagulase test
A
enterococcus
7
Q
what kind of hemolysis will streptococcus have?
A
alpha, beta and gamma
8
Q
what kind of hemolysis will enterococcus have?
A
gamma → not hemolytic
9
Q
gram + cocci in cluster is
A
staphylococcus
10
Q
A
Staphylococcus in clusters
gram +
11
Q
A
Streptococcus in chains
gram +
12
Q
A
Enterococcus → gram + cocci
cocci → coccobacilli
can form chains
13
Q
How do bacteria use catalase to survive?
A
Catalase is an extracellular enzyme.
It functions to inactivate hydrogen peroxide (producing oxygen) and free radicals in macrophages leading to intracellular survival
allows staphylococcus to travel around inside macrophages without being eaten
14
Q
how does catalase test work?
A
catalase produced by the bacteria will cause bubbles
staphylococcus is catalase + → catalase is also used to deactivate macrophages to allow staph to use them for movement
15
Q
a positive catalase test for a gram + cocci means ___
A
staphylococcus bacteria
hydrogen peroxide will react with catalase and produce O2 (bubbles)
16
Q
When you think skin infections… THINK ___
A
staphylococcus
17
Q
___ causes opportunistic infections of almost all body system
A
staphylococcus
gram + cocci
18
Q
___ causes canine pyoderma, greasy pig disease and bovine mastitis
A
staphylococcus
gram + cocci
19
Q
coagulase test
A
a staphylococcus test only!
coagulase binds to prothrombin and causes conversion of fibrinogen to fibrin → creates a clot
20
Q
staphylococci aureus cause what 3 diseases?
A
gram + cocci
equine SSTI, bovine contagious mastitis and avian bumblefoot
21
Q
equine SSTI, bovine cont. mastitis and avian bumblefoot is caused by ___
A
staphylococcus aureus
22
Q
Staphylococcus pseudintermedius (& S. schleiferi) cause what diseases ___
A
staph pseud
- pyoderma> otitis
- Canine & feline SSTI
- struvite urolithiasis (also proteus a gram -)
staph. schleiferi
- otitis> pyoderma
- Canine & feline SSTI
23
Q
staphylococci hyicus cause what diseases?
A
Greasy pig disease
24
Q
Greasy pig disease is causes by ___
A
staphylococcus hyicus
25
Canine & feline SSTI, pyoderma, struvite urolithiasis and otitis is caused by \_\_
**Staphylococci pseudintermedius →** gram + cocci that is coagulase +
* pyoderma\> otitis
* Canine & feline SSTI
* struvite urolithiasis (also proteus a gram -)
**Staphylococci schleiferi** → gram + cocci that is variable coagulase +
* otitis\> pyoderma
* Canine & feline SSTI
26
transmission of staphylococcus aureus to cats and dogs is by \_\_\_
anthropozoonotic transmission → from person to animal
27
staphylococcus aureus is a pathogen of \_\_\_
people, rare to find on cats and dogs
very common in horses
28
staphylococcus aureus in horses
cause SSTI → mostly post op infections
septic arthritis and osteomyelitis
29
horses are common carriers of nasal \_\_\_
MRSA
***Methicillin-resistant Staphylococcus aureus***
***(gram + cocci that is coagulase +)***
30
\_\_\_ is the bacteria usually found in post op infections in horses
staphylococcus aureus (gram +)
skin → think staph
31
Staphylococcus aureus will cause ____ in cattle
contagious mastitis
spread from cow to milking equipment to cow
32
\_\_\_ causes contagious mastitis in cows
staphylococcus aureus (gram + cocci, coagulase +)
strep. agalactiae
strep. dysgalactiae
33
bumblefoot is caused by \_\_\_
staphylococcus aureus (gram + cocci, coagulase +)
34
\_\_\_ is a chronic granulomatous process in the subcutaneous tissues of the foot caused by S. aureus
bumble foot
staphylococcus aureus (gram + cocci, coagulase +)
35
does S. pseudo or S. sch cause pyoderma
Staphylococcus pseudintermedius \> S. schleiferi
36
does S. pseudo or S. sch cause otitis
**S. schleiferi \> S. pseudintermedius**
gram + cocci, S. sch → variable coagulase, S. pseud → + coagulase
37
what causes struvite urolithiasis
Staphylococcus pseudintermedius
S. felis in cats
proteus (gram -)
38
\_\_\_ produce urease
Staphylococcus pseudintermedius and Staphylococcus felis → (gram + cocci)
proteus (gram -)
cause struvite urolithiasis
39
explain how urease works
enzyme that changes ammonia into ammonium
→ cause a urine pH increase → leads to crystal formation → stone(urolith) formation → bacteria will form on stones and form biofilm which makes them very hard to kill and cause a persistent infection
(Staphylococcus pseudintermedius and S. felis and proteus → produce urease cause struvite urolithiasis)
40
how does struvite urolithiasis form
(Staphylococcus pseudintermedius and S. felis produce **urease** which is an enzyme that changes ammonia into ammonium → cause a urine **pH increase** → leads to **crystal formation** → stone(urolith) formation → bacteria will form on stones and form **biofilm** which makes them very hard to kill and cause a **persistent infection**
cause struvite urolithiasis
these are gram + cocci
41
another name for greasy pig disease
exudative epidermitis (caused by staphylococcus hyicus)
42
greasy pig disease is caused by \_\_\_
staphylococcus hyicus (gram + cocci)
young 7 week old pigs secondary to fighting/biting
Often systemic and **rapidly fatal**, affects lungs, lymph nodes,
kidneys and brain.
Skin lesions characterized by a thick **grey-brown exudate** around face and ears.
43
staphylococcus hyicus cause \_\_\_
exudative epidermitis (greasy pig disease)
44
how to test for methicillin resistance
broth micro dilution to find MIC (minimum inhibitory concentration) using **Oxacillin**
## Footnote
**(beta lactam→ bactericidal and time dependent→ target cell wall synthesis by inhibiting PBP which cause NAG and NAM crosslinking in peptidoglycan)**
45
what are the sensitivity ranges for MRSP
\< 0.25 ng/ul = Sensitive
\> 0.5 ng/ul = Resistant
use oxacillin (type of beta lactam)
46
methicillin resistance is cause by the bacterial production of ___ that causes \_\_\_
PBP2a
will allow cross linking of NAG and NAM to build **peptidoglycan** even in the presence of antibiotic
encoded by the **mecA gene (SCC)**
47
what gene produces the enzyme PBP2a
mecA gene (SCC)
resistant to beta lactams → cause methicillin resistance → allow for NAG and NAM cross linking to make peptidoglycan
48
MRSA vs MRSP
methicillin resistance staphylococcus aureus
methicillin resistance staphylococcus pseudintermedius
49
sensitivity points for MRSA and MRSP
MRSA 2 and 4
MRSP \< 0.25= sensitive, \> 0.5= resistant
50
\_\_ confers resistance to ALL BETA LACTAM DRUGS
methicillin-resistance
mecaA gene (SCC) → PBP2a enzyme
51
streptococcus can be both ___ and \_\_\_
true pathogen and opportunists
52
Beta hemolysis
complete hemolysis can see through plate
blood agar plates
53
alpha hemolysis
greening/incomplete hemolysis
54
gamma hemolysis
no hemolysis
55
hemolysis testing is diagnostic for \_\_\_
streptococcus (gram + cocci in chains)
56
viridans streptococci
alpha hemolysis → incomplete/greening of blood agar plate
(commensal strep → usually clinically irrelevant)
hemoglobin changes to methemoglobin
57
what process causes alpha hemolysis
hemoglobin changes to methemoglobin
(commensal strep → usually clinically irrelevant)
58
alpha streptococcus
(commensal strep → usually clinically irrelevant)
59
what process causes Beta hemolysis
lyse erythrocytes and produce a clear zone of hemolysis
60
what are some Beta- streptococci
Streptococcus canis (group G)
S. equi subspecies. equi (group C)
S. equi subspecies zooepidemicus (group C)
S. agalactiae (B)
61
beta- streptococcus
can see through plate→ complete hemolysis
62
gamma streptococci are __ hemolytic
non (gamma)
63
gamma- strep are mostly \_\_\_
non-pathogenic or opportunistic pathogens
64
enterococcus will cause what type of hemolysis
gamma → no hemolysis
65
Group B strep include
streptococcus agalactiae → cause neonatal sepsis in human and contagious mastitis in cows
66
cause neonatal sepsis in human and contagious mastitis in cows
streptococcus agalactiae
| (group B strep)
67
streptococcus agalactiae cause \_\_\_
neonatal sepsis in humans
mastitis in cows
group B strep (gram + cocci)
68
\_\_\_ is used to confirm group B streptococcus
CAMP test
**Streptococcus agalactiae** (horizontal) will cause wedge shape in the presence of **staphylococcus aureus**
69
CAMP test is used to identify \_\_\_. Though not strongly beta- hemolytic on its own, it presents with a wedge- shape in the presence of \_\_\_\_
Streptococcus agalactiae (gram + cocci, group B strep)
Staphylococcus aureus (gram + cocci)
70
group C strep include
Streptococcus dysgalactiae
S. equi subspecies equi
S. equi subspecies zooepidemicus
71
S. dysgalactiae
group C strep
cause mastitis (mix of contagious and environmental)
72
\_\_\_ causes strangles in \_\_\_
group C strep
**Streptococcus equi subspecies equi (gram + cocci)**
horses
73
the clinical symptoms of S. equi subspecies equi are
strangles
fever, nasal discharge, severe lymphadenopathy
74
fever, nasal discharge and severe lymphadenopathy are symptoms of \_\_\_
strangles caused by group C strep → S. equi subspecies equi
75
strangles can spread by
direct and fomite spread
group C strep → S. equi subspecies equi
76
\_\_\_ cause endometritis and septic arthritis in horses
group C strep → Streptococcus equi subspecies zooepidemicus
77
S. equi subspecies zooepidemicus is found \_\_\_
in the horses mouth → opportunistic infection that causes endometritis and septic arthritis
group C strep (gram + cocci chains)
78
S. equi subspecies zooepidemicus will cause ___ in horses and ___ in dogs
**Pneumonia-** across MANY animal species
• Shipping fever, endometritis and septic arthritis in horses
• Severe, necrotizing, hemorrhagic pneumonia of dogs
Group C strep (gram + cocci strands)
79
S. agalactiae augments the hemolytic activity of staphylococcal beta-toxin via the action of the \_\_\_
CAMP factor
80
group G strep
S. canis
81
\_\_\_ is the most common strep in dogs and cats
group G. Streptococcus canis
82
S. canis is found \_\_\_
normal mucosal flora in dogs and cats
group C strep
83
\_\_\_ is the most common cause of endocarditis in dogs
group G strep
streptococcus canis
84
Group G strep is associated with ___ and \_\_\_in dogs
toxic shock syndrom
necrotising fasciitis
group G strep → S. canis (gram + cocci chains)
85
S. canis cause ___ in dogs
endocarditis, secondary pneumonia, toxic shock syndroma nd necrotizing fasciitis
group G strep (gram + cocci chains)
86
how does toxic shock syndrome work?
bacteria such as group G strep - **S. canis**
will bind to T cell forming a **superantigen** → leads to the overproduction of downstream cytokines (increased inflammation)
87
Group R strep
S. suis
88
group R strep cause ___ in pigs
Streptococcus suis (gram + cocci chains)
## Footnote
encephalitis, meningitis, arthritis, septicemia, abortion and endocarditis in pigs
89
what is so dangerous about group R strep
**S. suis** is zoonotic → can transfer from animal to human
## Footnote
**swine**
90
\_\_\_ is the agent of environmental mastitis in cattle
Streptococcus uberis/parauberis
non-groupable strep
91
\_\_\_ is a common respiratory pathogen in guinea pigs
Streptococcus pneumoniae
occasionally seen in horses, mainly a human pathogen
92
Streptococcus pneumoniae
non group-able strep
## Footnote
Common respiratory pathogen of **Guinea Pigs**
– Occasionally reported from horses
– **Mainly a human pathogen**
93
Group A strep
Streptococcus pyogenes
cause strep throat
94
\_\_\_ causes strep throat
streptococcus pyogenes
group A strep
95
what drug is used to treat strep?
penicillin
amazing **gram + activity,** some gram -, **narrow spectrum,** **aerobes,** some anaerobes
**beta lactam** ( bactericidal, time dependent, cell wall synthesis→ attack PBP which allow for NAG and NAM crosslinking in peptidoglycan)
96
what drug should not be used to treat strep
fluoroquinolones such as Baytril
97
\_\_ is just poop
enterococcus
formerly group D strep
normal fecal flora
98
enterococcus is intrinsically resistant to \_\_\_
**cephalosporins** (type of beta lactam→ cell wall)
**TMS**( potentiated sulfonamide→ folic acid)
**Clindamycin** (linocosamide→ protein synthesis)
**Fluoroquinolones** (DNA synthesis)
99
\_\_\_ is a type of enterococcus that is sensitive to penicillin
Enterococcus faecalis
is = is easy to treat
(gram + cocci/ coccobacilli pairs and chains)
100
E. faecalis
type of enterococcus (gram + cocci)
typically sensitive to penicillin
**is** easy to treat
101
\_\_ is a type of enterococcus that is resistant to penicillins
enterococcus faecium
um… how to treat this?
102
VRE
Vancomycin Resistant Enterococcus faecium
um… resistant to pencillin
hospital acquired pathogen
103
what 4 gram positive bacteria cause mastitis
**contagious**
staph. aureus
strep. agalactiae (group B strep)
strep. dysgalactiae (group C strep)
**environmental**
Strep. uberis/ parauberis (non groubable strep)
strep. dysgalactiae (group C strep)
104
what do staph. aureus, strep. agalactiae and strep. dysgalactiae have in common
**all cause contagious mastitis**
staph. aureus
strep. agalactiae (group B strep)
strep. dysgalactiae (group C strep)
105
gram positive cocci that are catalase positive are
106
gram positive cocci that are catalase negative are
107
108
\_\_\_ cause equine SSTI, avian bumblefoot and contagious bovine mastitis
Staphylococcus Aureus
gram + cocci, catalase +, coag +
109
\_\_\_ cause struvite urolithiasis, pyoderma, otitis
staphylococcus pseudintermedius
gram + cocci, catalase +, coag +
110
\_\_\_ cause otitis, pyoderma
staphylococcus schleiferi
gram + cocci, catalase +, variable coag
111
\_\_\_ cause struvite urolithiasis
S. felis → gram + cocci, catalase +, coag -
S. pseudintermedius → gram + cocci, catalase +, coag +
Proteus → gram -
112
\_\_\_ causes exudative epidermitis (greasy pig)
staphylococcus hyicus
gram +, catalase +, variable coag
113
Group B- \_\_\_- contagious mastitis and neonatal sepsis
S. agalactiae
CAMP test
gram + cocci, catalase -
114
Group C- \_\_\_- contagious and environmental mastitis
Streptococcus dysgalactiae
gram + cocci, catalase -
115
Group C- ____ -strangles
Streptococcus equi subspecies equi
gram + cocci
116
Group C- \_\_\_- Opportunistic infection- shipping fever, endometritis, septic arthritis/pneumonia
Streptococcus equi ssp. zooepidemicus
gram + cocci, catalase negative
117
Group G- \_\_\_- invasive Opportunistic infection- endocarditis/contaminant -TSS, necrotizing fasciitis
Streptococcus canis
gram + cocci chains, catalase negative
118
Group R, S, T- \_\_\_- septicemia/zoonotic
Streptococcus suis
encephalitis, meningitis, arthritis septicemia, abortion, endocarditis
gram + cocci chains, catalase -
119
Non-groupable- \_\_\_- environmental mastitis
S. uberis/parauberis
S. pneumoniae → humans and guinea pigs
gram + cocci chains
120
two types of enterococcus
**E. faecalis**- Opportunistic infection/Contaminant → penicillin
**E. faecium**- Opportunistic infection/Contaminant→ resistant to penicillin
