Micro- Bacteria Flashcards
1
Q
Which part of GN and GP are the major cytokine inducers?
A
GN: lipid A- TNF, IL1
GP: LTA- TNF, IL1
2
Q
Describe the cell membrane/ cell wall of mycoplasma
A
contains sterols
no cell wall
3
Q
Describe the cell membrane/cell wall of mycobacteria
A
contains mycolic acid
high lipid content
4
Q
What staining can be used to detect Legionella?
A
silver stain
5
Q
What does Ziehl-neelsen staining detect?
A
acid fast organisms
Nocardia, Mycobacterium
6
Q
What does india ink staining detect?
A
Cryptococcus neoformans
7
Q
What does sabouraud agar culture?
A
Fungi
8
Q
What does Thayer-martin agar culture?
A
Neisseria
9
Q
What does Bordet-Gengou agar culture?
A
B. pertussis
10
Q
What Tellurite agar culture?
A
C. diptheria
11
Q
What does Lowenstein-Jenson agar culture?
A
M. tuberculosis
12
Q
What does Eaton agar culture?
A
M. pneumonia
13
Q
What does charcoal yeast extract agar culture?
A
Legionella
14
Q
What are 3 examples of obligate anaerobes? What are some clinical features of them?
A
Clostridium, Bacteroides, Actinomyces
foul smelling, produce gas in tissue, dont treat with aminoglycosides
15
Q
What are 2 examples of obligate intracellular bacteria?
A
Chlamydia, Rickettsia
16
Q
What is the mechanism of Protein A and what organism expresses it?
A
Binds Fc region IgG, prevents opsonization and phagocytosis
S. aureus
17
Q
What organisms express IgA protease? What is this important to colonize?
A
S. pneumo, H. flu, Neisseria
imp for colonizing resp tract
18
Q
What does M protein do and what organism expresses it?
A
GAS
prevents phagocytosis
19
Q
What toxin does C. diptheria produce? What is mechanism?
A
Diptheria toxin
Inactivation of elongation factor (EF-2)
20
Q
What toxin does P. auruginosa produce? What is the mechanism
A
Exotoxin A
Inactivation of elongation factor (EF-2)
21
Q
What toxin does shigella produce? What is the mechanism?
A
Shiga toxin
inactivate 60s ribosome- remove adenine from rRNA
HUS
22
Q
What toxin does EHEC produce? What is the mechanism
A
Shiga-like toxin
inactivate 60s ribosome- remove adenine from rRNA
HUS
23
Q
What toxins do ETEC produce? What are mechanisms?
A
Heat-labile toxin (LT)- incr cAMP (via adenylate cyclase)- Cl- secretion
Heat-stable toxin (LT)- incr cGMP- decr NaCL resorption
24
Q
What toxin does vibrio cholerae produce? What is the mechanism?
A
Cholera toxin
incr cAMP by permanently activating Gs
incr CL- secretion
25
What toxin does Bordetella pertussis produce? What is the mechanism?
Pertussis toxin
| incr cAMP by disabling Gi, impairs phagocytosis
26
What toxin does Clostridium tetani produce? What is the mechanism?
Tetanospasmin- protease cleaves SNARE prot
| spacticity, lock jaw- act on inhibitory neuronotransmitters (GABA, glycine)
27
What toxin does Clostridium botulinum produce? What is the mechanism?
Botulinum toxin- protease cleaves SNARE prot
| flaccid paralysis- act on stimulatory neuronotransmitters (Ach)
28
What toxin does Clostridum perfinges produce? What is the mechanism?
Alpha toxin
phospholipase- degrades tissue and cell membranes
gas gangrene, hemolysis
29
What toxin does S. pyogenes produce? What is the mechanism?
Streptolysin O
Degrades cell membranes
Lyses RBC
30
What superantigen does S. aureus produce? What is the mechanism?
TSST-1
| Bring MHC II and TCR in proximity
31
What superantigen does S. pyogenes produce? What is the mechanism?
Exotoxin A
| Bring MHC II and TCR in proximity
32
Compare generalized vs specialized transduction
Generalized- packaging event, lytic phage
| specialized- excision event, lysogenic phage
33
Novobiocin sensitive
S. epidermidis
34
Optochin sensitive
S. pneumOnia
35
Bacitracin sensitive
S. pyogenes
| group A strep
36
Catalase negative, a hemolytic (2)
S. pneumoniae
| Viridans streptococci
37
GP, catalase negative, a hemolytic, bile insoluble
Viridans streptococci
38
GP, catalase negative, non-hemolytic (2)
| How differentiate?
```
Group D (enterococcus- E. faecalis)- Grow in 6.5% NaCl
Nonenterococcus (S. bovis)- Don't grow in 6.5% NaCl
```
39
b-hemolytic GP rod
Listeria
40
What GP organism is likely to cause abscesses? What is the mechanism?
S. aureus
| forms fibrin clots around self (coagulase and other toxins)
41
What GP organism is likely to cause dental carries?
S. mutans
42
What GP organism makes dextrans? What does this cause?
S. sanguinis
| endocarditis (via binding to fibrin-platelet aggregates)
43
What 4 diseases is S. pneumo the most common cause of?
```
MOPS
Meningitis
Otitis media
Pneumonia
sinusitis
```
44
CAMP test +
Group B strep
45
ELEK test
C. diptheria
46
What vaccine is given to prevent diphtheria?
Toxoid vaccine
47
Causes pseudomembranous pharyngitis with grayish-white membrane. What are other risks?
Diphtheria
| myocarditis and arrhythmia
48
What is the only bacteria with a polypeptide capsule?
B. anthracis
| contains D-glutamate
49
What is woolsorter's disease?
inhalation of anthrax spores from contaminated wool
50
What food poisoning is associated with rice and past? What is toxin?
B. cereus
| cereulide toxin- preformed- 1-5h after eating
51
Flu-like symptoms that rapidly progress to fever, pulm hemorrhage, mediastinitis, shock
pulmonary anthrax
52
What is the only gram positive organism to produce LPS?
Listera monocytogenes
53
What are the GP branching filament organisms? How differentiate?
Actinomyces- Anaerobe, not acid fast
| Nocardia- Aerobe, acid fast
54
What causes amnionitis, septicemia, and spontaneous abortion and mild gastroenteritis in adults?
L. monocytogenes
55
What is the common source of Listeria?
unpasteurized dairy products and deli meats
56
What is the treatment for listeria?
Ampicillin
57
What is used to treat Actinomyces?
penicillin
58
What is used to treat Nocardia?
sulfonamides
59
What are the virulence factors of mycobacteria do?
Cord factor- inhibits macrophage maturation, induces release of TNFa
Sulfatides- inhibit phagoysosomal fxn
60
What is the prophylactic treatment for MAC?
azithromycin
61
What is the treatment for lepromatous vs tuberculoid Tb?
Lepromatous- dapsone, rifampin, clofazimine 2-5yrs
| Tuberculoid- dapsone, rifampin, 6mo
62
Oxidase+, comma shaped, grows in 42 deg
Campylobacter
63
Oxidase+, comma shaped, grows alkaline media
vibrio cholerae
64
Oxidase+, comma shaped, produces urease
H. pylori
65
Gram Neg diploccoci, Maltose fermenter
N. menigitidis
66
Gram Neg diploccoci, non-maltose fermenter
N. gonorrhea
67
GNR, NLF, Ox+
Pseudomonas
68
GNR, LF (2)
Klebsiella, E coli
69
GNR, NLF, Ox- (4)
Shigella
Salmonella
Proteus
Yersinia
70
EMB agar- LF vs NLF
LF- purple/black colonies
71
Treatment of Neisseria
ceftriaxone (or penicillin G)
72
H. flu treatment
mucosal
menigitis
menigitis prophylaxis
mucosal: amoxicillin +/- calvulanate
menigitis: ceftriaxone
menigitis prophylaxis: rifampin
73
What causes epiglottitis?
H. flu
74
GN coccobacilli (2-4)
H. flu
Bordetella pertussis
pasteurelis
brucella
75
What type of pneumonia also has hyponatremia?
Legionella
76
Treatment of Legionella
macrolide or quinolone
77
What causes malignant otitis externa in diabetics?
P. arueginosa
78
What causes hot tub folliculitis?
P. aeruginosa
79
What is ecthyma gangrenosum? What causes it?
necrotic cutaneous lesion, P. aeruginosa
80
What is the treatment of P. aeruginosa?
aminoglycoside + extended spectrum penicillin
81
What is the E. coli virulence factor for pneumonia and neonatal meningitis?
K capsule
82
What is the E. coli virulence factor for cystitis and pyelonephritis?
fimbriae
83
What infection is common for burn patients
P. aeruginosa
84
What does EIEC cause?
Dysentery
| invades intestinal mucosa- necrosis and inflammation
85
What does EPEC cause?
Diarrhea, often in childreen
| no toxin, adhere to apical surface, flattens villi, prevent absorption
86
What type of E. coli does not ferment sorbitol?
EHEC
87
What does ETEC cause?
```
Travelers diarrhea (watery)
heat-labile or heat-stable toxin
```
88
What commonly causes lobar pneumonia in acoholics and diabetics
Klebsiella
89
Where does S. typhi remain in carrier state?
Gallbladder
90
What type of inflammatory response is associated with shigella vs salmonella?
Salmonella- monocytic
| Shigella- PMN
91
What diarrhea causing organism often causes Guillain-Barre and reactive arthritis?
Campy
92
Rice water diarrhea
Cholera
93
Can cause mesenteric adenitis; can get from pets
Yersinia enetrcolitica
94
Treatment for H. pylori
PPI+clarithromycin+ amoxicillin or metronidazole
95
What are the 3 spirochetes?
Borrelia (big)
Leptospira
Treponema
96
Flu-like sx, jaundice, photophobia with conjunctival suffusion
Leptosporosis
97
What is the cause of leptosporosis?
Animal urine in water
98
What is Weil disease?
severe form of leptosporosis
| fever, hemorrhage, anemia (liver + kidney dysfunction)
99
What are the lesions associated with primary vs secondary vs tertiary syphillis?
Primary: chancre
Secondary: condyloma lata, rash on palms and soles
Teritary: gumma
100
Presents with saber shins, saddle nose, CNVIII deafness, mulberry molars
congenital syphillis
101
What is the natural reservoir of Borrelia burgdorferi?
Mouse
102
Presents with erythema chronicum migrans, flu-like symptoms, facial nerve palsy
Lyme disease
103
Presents as monoarthritis, AV nodal block, migratory polyarthritis, neuro
Lyme disease
104
Treatment of Lyme disease
doxycycline, ceftriaxone
105
What is the Jarisch-Herxheimer reaction?
Flu-like sx after starting antibiotics- killed bacteria release pyrogens
106
What organisms are carried by the Ixodes tick?
Anaplasmosis
| Borrelia burgdorferi
107
What is associated with clue cells?
gardnerella vaginalis
108
What is associated with LAD with stellate granulomas with central necrosis?
Bartonella henselae (gram neg bacillus)
109
What is the treatment for Ricketssia and vector-borne illness?
doxycycline
110
Presents with a rash starting centrally that spreads out, sparing palms and soles
Typhus
111
What are the vectors for typhus?
Endemic (R. typhi)- fleas
| Epidemic (R prowazekki)- human body louse
112
Presents as a rash starting at wrists and ankles, spreads to trunk, palms, soles
Rickettsia
113
Present with monocytes with morulae in cytoplasm (2), rash rare
Ehrilchiosis, anaplasmosis
114
Presents with pneumonia, rash rare, no arthropod vector
Q fever
| Coxiella burnetti
115
Presents as small painless ulcers on genitals that progress to swollen, painful inguinal LN that ulcerate
Chlamydia trachomatis
| Types L1, L2, L3
116
Treatment for chlamydia
azithromycin or doxycycline
117
What are the two forms of chlamydia?
Elementary bodies- enters cell via endocytosis, small and dense
Reticulate bodies- replicate in cell by fission
118
Causes blindness due to follicular conjuctivitis in Africa
C. trachomatis
| Types A, B, C
119
Pneumonia presents with insidious onset, headache, nonproductive cough, patchy or diffuse interstitial infiltrate
Common in younger individuals
Myocplasma pneumoniae
120
What is the treatment for mycoplasma pneumonia
macrolide, doxycycline, flouroquinolone
121
positive for RBC agglutination, lysis of RBCs
mycoplasma pneumonia
