Micriobio: Gram positive Flashcards
1
Q
which type of bacteria has a cell wall/cell membrane
A
this is in gram positive. it is mostly peptidoglycan for support and has lipotechoic acid which induces TNF and IL1.
2
Q
which type of bacteria has an outer membrane
A
this is in gram negatives and it has lipid A which induces TNF and IL1. it also can have O polysaccharide which is the antigen
3
Q
which type of bacteria has the periplasm?
A
this is in the gram negative and it has hydrolytic enzymes including beta lactamases
4
Q
which bacteria has a capsule that is not made of polysaccharide?
A
B anthracis and it is made of D glutamate
5
Q
why can’t you stain mycoplasma
A
no cell wall. the cell membrane contains steroids
6
Q
why can’t you stain mycobacteria
A
cell wall has mycolic acids and a high lipid content
7
Q
pneumonic for those that don’t stain
A
These Microbes May Lack Real Color Treponema Mycobacteria Mycoplasma Legionella (silver stain) Rickettsia (intracellular parasite) Chlamydia (intracellular and lacks muramic acid)
8
Q
Giemsa stain
A
Certain Bugs Really Try my Patients Chlamydia Borrelia Rickettsiae Trypanosomes Plasmodium
9
Q
PAS stain
A
tropheryma whipplei
10
Q
Ziehl Nelson Stain
A
Nocardia and Mycobacteria- this is an acid fast stain
11
Q
India ink stain
A
cryptococcus neoformans
12
Q
Silver stain
A
fungi, legionella, H pylori
13
Q
special media requirements for H influenzae
A
chocolate agar with factor V (NAD+) and factor X (hemetin)
14
Q
special media for Neisseria
A
thayer martin or VPN media
V- vanco against gram positives
P- polymyxin against gram neg except Neisseria
N - nystatin against fungus
15
Q
special media for Bordetella pertussis
A
Bordet Gengoup (potato agar)
16
Q
special media for C diptheriae
A
tellurite agar. loffler medium
17
Q
special media for TB
A
lowenstein Jensen agar
18
Q
special media for M pneumoniae
A
Eaton agar, requires cholesterol
19
Q
lactose fermenting bugs
A
these guys like E coli are pink on Maconkey and purple with a green metallic sheen on EBM or eosin methylene blue
20
Q
special media for legionella
A
charcoal yeast extract with iron and cystine
21
Q
special media for fungi
A
Sabouraud agar.
22
Q
pneumonic for obliagate aerobes
A
Nagging Pests Must Breathe
Nocardia, Pseudomonas, MycoBacterium,
23
Q
pneumonic for oligate anerobes
A
can’t breathe air
clostridium
bacteriodes
actinomyces
remember that anerobes are resistant to all aminoglycosides because they require O2 to be taken up into the cell.
24
Q
intracellular bugs
A
Really Cold
Rickettsia
Chlamydia
25
Facultative intracellular
```
Some Nasty Bugs May Live FacultativeLY
Salmonella
Neisseria
Brucella
Mycobacteria
Listeria
franciesella
Legionella
Yersinia pestis
```
26
encapsulated bacteria
SHiN
S. pneumonia
H influenza
N meningitidis
27
catalase positive organisms
```
PLACESS
psuedomonas
listeria
aspergillus
candida
Ecoli
S aureus
Serratia
```
28
3 conjugate vaccines
S pneumonia, H influenza, N meningitidis
29
urease positive bugs
```
cryptococcus
H pylori
Proteas
Ureplasma
Nocardia
Klebsiella
S epidermidis
S saprophyticus
```
30
color of serratia marcescens
red pigment.
31
function of protein A
binds to Fc region of IgG. prevents opsonization and phagocytosis
32
bug that expresses protein A
Staph aureus
33
IgA protease function
enzyme that cleaves IgA
34
bugs that have IgA protease
SHiN organisms
35
M protein function
helps prevent phagocytosis
36
bug that has M protein
group A strep
37
endotoxin is gram negative or positive
negative
38
exotoxin is gram negative or positive
both
39
where is the endotoxin
in the cell membrane of the gram negative bacteria and it is released when the cell is lysed
40
where is the exotoxin?
secreted from the cell
41
endotoxin location of genes
bacterial chromosome
42
exotoxin location of genes
plasmid or bacteriophage
43
which two bacteria have exotoxins that inhibit EF2
corynebacteria diptheria and psuedomonas aerginosa
44
shiga and shiga like exotoxin effect
inactivate the 60S ribosome by removing the adenine from the rRNA
45
Enterotoxigenic Ecoli has two exotoxins
Heat labile- overactivates cAMP and increases Cl secretin into the gut.
Heat stabile- increases guanylyl cyclase increasing cGMP and decreasing NaCL reabsorption in the gut
46
edema factor exotoxin found in which bug
bacillus anthracis. mimics the adnylate cyclase enzyme and increases cAMP. gives the black border on eschar lesions
47
cholera toxin
this is in vibrio cholera and it overactives adenylate cyclase and increases cAMP by permanently activating Gs. causes increase in Cl secretion into the gut and water to follow
48
pertussis toxin
seen in bordatella pertussis. increase cAMP by disabling Gi impairing phagocytosis to permit survival. this causes whooping cough
49
tetanospasmin enterotoxin
this is in C tetani. it is a protease that cleaves the SNARE proteins, preventing NT release. this works on the inhibitory GABA and glycing neurons of the Renshaw cells of the spinal cord. causes risus sardonicus and lock jaw
50
alpha toxin
this is from C perfringes. it is a phospholipase or lecithinase that degrades tissue and cell membranes. gives gas gangrene and double hemolysis on blood agar
51
streptolysin O enterotoxin
this is in S pyogenes. protein that degrades cell membrane. lyses RBCs, contributes to beta hemolysis etc.
52
Exotoxin A
this is found in psueodmonas where it is an inihbitor of E2F and it is found in Strep pyogenes where it brings the MHC II and TCR in proximity to cause an overwhelming release of IFN gamma and IL2 leading to shock. toxic shock syndrome
53
TSST-1 extoxin
this is from S aureus. brings MHC II with TCR to cause increase in IFN gamma dn IL2 leading to shock.
54
two organisms that cause toxic shock syndrome
S pyrogenes and S aureus
55
novobiacin use
to distinguish staph organisms. saprophyticus is resistant and epidermitis is sensistive. No Stress.
56
optochin use
works on alpha hemolytic strep.
| viridans is resistant and pneumonia is sensative
57
bacitracin
works to distinguish beta hemolytic strep organisms.
| Group B strep is resistant and Group A or pyogenes is sensitive.
58
green ring on blood agar
this means the colonies are alpha hemolytic
59
clearing on the blood agar plate
this means the colonies are beta hemoltic
60
4 beta hemolytic organisms
S aureus
strep pyogenes
Strep agalactiae
Listeria monocytogenes- tumbling motility
61
gram positive clusters
staph!
62
gram positive chains
Strep
63
two organisms that are branching gram positive filaments
Nocardia and actiomyces
64
how to distinguish nocardia from actinomyces
actinomyces is anaerobe, not acid fast
| nocardia is mildly acid fast and aerobe
65
what is special about group D strep
enteroccocus. grows in bile and in 6.5% NaCL
| example- E faecalis
66
Nonenteroccus
this is different from group D strep because it grows in bile but not in 6.5% NaCL.
example- S bovis
67
organism that causes skin infections, organ abscesses, pneumonia, endocarditis and osteomyelitis
S aureus
68
what is the mutation in MRSA that makes methicilin resistant
mutation in the penicillin binding protein (PBP)
69
what two things does S aureus produce
catalase (just because it is staph) and then it also makes coagulase
70
bug that infects prosthetic devices and IV catheters by producing adherent biofilms
S epidermis. often a contaminant of blood cultures because it is a normal part of the flora
71
second most common cause of uncomplicated UTI in young women
Staph saprophyticus
72
4 conditions caused by Strep pneumoniae
```
MOPS
Meningitis
Otitis media
Pneumonia
Sinusitis
```
73
lancet shaped gram positive diplococci
Strep pneumniae
74
what is the virulence factor with Strep pneumoniae
IgA protease and encapsulated.
75
rusty sputum and sepsis in sickle cell anemia and splenectomy patients
Strep pneumonia infection
76
bug that causes dental caries
Strep viridans (Strep mutans)
77
bacteria that causes subacute bacterial endocarditis at damaged valves
Strep viridans (strep sanguinis)
78
cause of rheumatic fever
Strep pyogenes
79
Jones criteria
```
this is for rheumatic fever
migrating arthalgias
subcutaneous nodules
carditis
erythema marginatum
syndham chorea
```
80
Strep pyogenes pharyngitis can cause
this can cause rheumatic fever or glomerulonephritis
81
Strep pyogenes imetpigo infection can cause
mostly just leads to glomerulonephritis.
82
scarlet fever
this is scarlet rash, sandpaper like texture, strawberry tongue, circumoral pallor
83
another name for group B strep
strep agalactae
84
disease normally caused by Group B strep
colonizes vagina, causes pneumonia, meningitis and sepsis, mostly in babies
85
CAMP factor
this is produced by group B strep and it increases the hemolytic area formed by S. aureus.
86
bacteria that gives a positive hippurate test
group B strep
87
when should women be screened for group B strep
35-37 weeks
88
enteroccoci
normal colonic flora that are penicillin G resistant and cause UTI, biliary tract infections and subacute endocarditis (most commonly after Gi/GU procedures)
89
subacute endocarditis after GI/GU procedure
enterococcus
90
subacute endocarditis with colon cancer
Strep Bovis
91
acute endocarditis
S. aureus
92
subacute endocarditis of damaged valves
Viridans strep- most specifically S sanguinis
93
what is lancefield grouping based on
C carbohydrate on the bacterial cell wall. variable hemolysis. includes both enterococcus and non enterococcus
94
how to differentiate enterococci from non enterococci
the non enterococci cannot grow on 6.5% naCl while the enterococci can. both can grow in bile
95
strep bovis infection
colonizes the gut. can cause bacteremia or subacute endocarditis in colon cancer patients.
96
corynebacterium diptheriae
causes diptheriae via exotoxin encoded by beta prophage. potent exotoxin inhibits protein synthesis via ADP ribosylation of EF2.
97
symptoms of corynbacterium diptheriae infection
pseudomembranous pharyngitis, lymphadenopathy, myocarditis, and arrythmias.
98
Elek test
this is for the toxin from corynbacteria diptheraie
99
lab shows gram positive rods with metachromatic blue and red granules
this is positive for corynbacteria diptheraie
100
intracellular polyphosphate granules which are metachromatic with methylene blue staining
this is positive for corynbacteria diptheraie
101
black colonies on cystine-tellurite agar
this is positive for corynbacteria diptheraie
102
how do we kill spores in the hospital
must autoclave to kill spores- by steaming to 121 for 15 minutes
103
spore forming organisms from soil
bacillus anthracis, C perfringes, C tetani
104
non soil spore forming organisms
B cereus, C botulinum, Coxiella burnetti
105
organism that produces tetanospasmin
C tetani
106
organism that produces alpha toxin
C perfringes. this is a lecithinase, a phospholipase that can cause myonecrosis or gas gangrene and hemolysis.
107
organism that produces two toxins- Toxin A and Toxin B
this is C diff
108
Toxin A and Toxin B from C diff
Toxin A: enterotoxin: binds to the brush border of the gut.
Toxin B: cytotoxin: cytoskeletal disruption via actin depolymerization and this is what leads to psuedomembranous colitis.
109
two antibiotics commonly causing C diff infections
clindamycin and ampicillin.
110
treatment for C diff infection
metronidazole, or oral vancomycin
111
lab shows lancet shaped gram positive diplococci
this is strep pneumoniae
112
symptom of cutaneous anthrax
boil like lesion that turns to an ulcer with black eschar which is painless and necrotic. unlikely to become septic or anything.
113
symptoms of pulmonary anthrax
inhalation of spores- gives flu like symptoms that rapdily progress to fever, pulmonary hemorrhage, mediastinitis and shock
114
vomiting and nausea from cereulide
this is the toxin from bacilis cerues that causes emetic type of illness seen with rice and pasta consumption. nausea and vomiting will start within 1-5 hours of infection. it is a preformed toxin.
115
diarrheal type of Bacillus cereus
this type causes watery non bloody diarrhea and GI pain within 8-18 hours
116
listeria monocytogenes
facultative intracellular microbe
117
organism that forms rocket tails via actin polymerization that allows them to move through cytoplasm with head over tail movement (tumbling motility) to avoid antibodies
this is listeria monocyotgenes
118
only one gram positive organism to produce LPS
listeria monocytogenes
119
how to treat infants and elderly with listeria infections
ampicillin
120
organism that causes oral/facial abcesses that drain through sinus tracts, form yellow sulfur granules
actinomyces
121
organism that causes pulmonary infections in immunocompromised patients and cutaneous infections after trauma in immuno normal or competent people
nocardia
122
how to treat actinomyces infections
penicillin
123
how to treat nocardia infections
treat with sulfonamides
124
which organism is gram positive but weakly acid fast
nocardia
125
prophylatic treatment in AIDS patient with mycobacterium avium intracellurae infection
azithromycin
126
what is the cord factor
this is found in virulent strains of mycobacterium and inhibits macrophage maturation and induces release of TNF alpha.
127
which organisms have sulfatides
this is found with cord factor in mycobacterum. it is a surface glycolipid that inhibits phagolysosomal fusion
128
which form of leprosy has more of a TH2 response?
lepromatous (low cell mediated immunity)
129
which form of leprosy has more of a TH1 cell mediated response
Tuberculoid
130
which form of leprosy shows the lion faces
this is lepromatous
131
treatment for leprosy
dapsone and rifampin with clofazimine if lepromatous. if tuberculoid you do not need the clofazimine.
132
how long is treatment for leprosy
2-5 years
