Micro Midterm 2 Flashcards
(282 cards)
1
Q
Is Neisseria gonorrhea gram negative or positive
A
Gram negative
2
Q
What is the shape of neisseria gonorrhea
A
diplococci
3
Q
Is neisseria gonorrhea cytochrome oxidase positive or negative
A
positive
4
Q
What are 2 nonliving infectious agents?
A
Prions and bacteria
5
Q
What are prions?
A
- abnormally configured self-replicating protein templates
- Prions are proteins that adopt beta pleated configuration, so they dont work well and start causing neurological disease
6
Q
What are viruses?
A
Nucleic acid (DNA or RNA) genes packaged in protein coats which can subvert host cells to replicate virus particles.
7
Q
What are the 2 types of prokaryotes?
A
archaea and bacteria
8
Q
What are some examples of eukaryotes?
A
animals (including worms), plants, fungi, algae, and protozoa
9
Q
What is the defining factor of eukaryotes?
A
nuclear membrane
10
Q
What are the characteristics of eukaryotes?
A
- nuclear membrane
- Multiple chromosomes
- Double stranded DNA
- Subcellular organelles (e.g., chloroplasts, mitochondria)
- Larger ribosomes 80S, bound to endoplasmic reticulum (rough ER)
- Larger cells, 10-100 um
11
Q
What do eukaryotes have that prokaryotes dont?
A
nuclear membranes and rough ER (and other subcellular organelles)
12
Q
What are characteristics of prokaryotes?
A
- no nuclear membrane (nucleoid)
- Single circular DS DNA chromosome
- No subcellular organelles
- Smaller ribosomes (70S), free in cytoplasm
- Smaller cell size (0.2-3 um diameter)
13
Q
Which organisms have cell walls?
A
prokaryotes and plants
14
Q
Which organisms have rigid cell walls?
A
most bacteria
15
Q
Which organisms have flexible cell walls?
A
spirochaetes
16
Q
What are cell walls?
A
osmotic barriers found in prokaryotes and plant cells
17
Q
List of classification for bacteria of medical importance:
A
- Cell wall
- Filamentous vs simple unicellular
- Obligate intracellular vs free-living
- Aerobic vs anaerobic
- Gram positive vs gram negative
- shapes (rods vs cocci)
- Glucose fermenters vs nonfermenters
18
Q
Are most bacteria filamentous or simple, unicellular?
A
simple, unicellular
19
Q
Are most bacteria obligate intracellular or free living?
A
free living
20
Q
Which bacteria are obligate intracellular?
A
chlamydia, coxiella, ehrlichia, rickettsia
21
Q
What is the definition of aerobic?
A
Tolerate significant concentrations of ambient oxygen, does not imply use of oxygen
22
Q
What is the definition of anaerobic
A
Poisoned by significant concentrations of ambient oxygen
23
Q
Who invented the gram stain?
A
Hans Christian Gram, a danish physician
24
Q
Which violet do they use for the gram stain now?
A
crystal violet instead of gentian violet
25
What is the red counterstain?
safranine, used to stain the decolourized (gram-negative) organisms
26
Describe the gram-positive cell wall.
Simple thick layer of peptidoglycan outside of the cell membrane. Contains techoic acid
- Simple matrix of peptidoglycan with some polymers (esp. techoic acid), exterior to the cytoplasmic membrane
27
Describe gram negative cell wall
complex structure with inner and outer membranes, LPS, porin proteins and thin peptidoglycan layer
- thin layer of peptidoglycan anchored inside the outer membrane (a structure not found in Gram positive bacteria) by murein lipoprotein
28
Gram positive or gram negative: porin proteins
Gram negative
29
Gram positive or gram negative: techoic acid
gram positive
30
Gram positive or gram negative: LPS
gram negative
31
What does LPS stand for?
Lipopolysaccharide
32
What are the different shapes of bacteria?
- Cocci (chains vs clusters)
- Rods (bacilli) cylindrical
- Short rods (coccobacilli)
- Curved
- Spiral
- Branched (filamentous)
33
What is an example of cocci shaped bacteria?
staph
34
What is an example of rod shaped bacteria
Salmonella typhi
35
What is an example of short rods?
haemophilus ducreyi
36
What is an example of a curved road bacteria
Vibrio cholera
37
Vibrio Cholerae
- Gram-negative curved rod with single flagellum (polar)
- mainly water borne
- non-invasive intestinal infection
- Major virulence factor is secreted cholera toxin
38
Composition of cholera toxin
Central active subunit A surrounded by a pentameric receptor-binding subunit B. The subunit A is responsible for the toxic activity
39
Which bacteria cause Japanese rat fever?
spirillum minus
40
What is an example of spiral bacteria
Spirillum minus
41
What is fermentation?
The anaerobic metabolism of sugars
42
Which type of bacteria is fermentation used to type?
gram-negative
43
What is a group that is hard to identify and treat?
nonfermenters
44
Why are prokaryote cells so small?
Because they dont have guts
45
which cells have a higher surface area to volume ratio (X20)
prokaryotic cells
46
High surface to volume ratio = ?
greater metabolic activity
47
What are the 3 explanations as for why gonorrheae is referred to as the clap?
- Le clapatier, area in France
- Clapoire: means pus forming
- Mother clap, in england (died from drive by fruiting)
48
What are capsules
Hydrophobic extracellular polysaccharides or protein polymers.
- They resist phagocytosis
49
Examples of slime layers:
biofilms
Glycocalyx
Plaque (on teeth)
Vegetations (on heart)
50
What are cytoplasmic membranes?
- Very similar to that of eukaryotic cells: phospholipid bilayer
- Metabolically active
- Invaginations called mesosomes
51
gram negative or gram positive: high pressure (5 to 20 atm)
Gram positive
52
Gram negative or positive: Lower pressure (3 to 5 atm)
gram negative
53
What does peptidoglycan do?
Stiffener and osmotic shield
54
What is the composition of peptidoglycan?
Alternation subunits of monosaccharides N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM), cross linked at NAM by peptide chains
55
What are lipopolysaccharides?
- AKA endotoxin
- Found in gram negatives
Three components: O antigen, core polysaccharide, lipid A
- Lipid A puts the toxin in endotoxin
56
Why do people go into shock when they are infected with gram negative bacteria?
- Because they have lipopolysaccharides which are endotoxins with 2 components ( O antigen, core polysaccharide, and lipid A)
57
Characteristics of mycobacteria cells walls:
- Acid fast: resistant to decolorization by even acid
- Similar to gram positives, but contains more lipids (60%, including a unique class of long chain Beta-hydroxylated fatty acids called mycolic acids
58
What do pili do?
- AKA fimbriae
- Mediate adhesion to other cells
- Specialized sex pili mediate conjugation
59
What is transduction?
It is the spreading of a virus
60
What is flagella?>
- Whiplike structures responsible for cell motility
- Hollow tube and basal body, composed of flagellin
- Require cell energy to move
- Only motile bacteria have them
- Carry H antigens
- polar vs peritrichous
61
What is associated with H antigen?
flagella
62
What are spores?
- Repackaged copies of bacterial DNA in highly impermeable, 6-layered envelope. Does not divide
- 2 cell membranes with 2 layers of peptidoglycan in between, keratin coat, lipoprotein exosporium
- Germinates to vegetative (dividing) bacteria after activation
- Bacillus (aerobic) and Clostridium (anaerobic) only
63
Which bacteria form spores?
Bacillus (aerobic) and Clostridium (anaerobic)
64
What are aerobic gram positive cocci?
Staphylococci and streptococci
65
Which bacteria looks like grapes?
staphylococcus
66
Where can you find staphylococcus aureus?
- In the anterior nares, skin and throat
67
What is special about staph aureus (specific test)
coagulase positive
68
Which is the nastiest staph (99%)
staph aureus
69
Which is the coagulase positive staph?
staph aureus
70
What are staph aureus virulence factors?
Cell wall virulence factors:
- Protein A: which binds to the Fc portion of IgG and inhivits phagocytosis
- Fibronectin-binding protein (FnBP)
Membrane damaging exotoxins:
- alpha, beta, gamma, omega, and leukocidin
Superantigens exotoxins:
- these protein toxins have an affinity for relatively highly conserved region of the T cell receptor, the MHC class II complex. They stimulate a massive T-cell response (app. 20%, contrasted with the usual 0.01%) with outpouring T cell cytokines TNF-alpha, IL-2, and interferon-gamma.
- Exfoliatin: causes expanded staph scalded skin syndrome
- Enterotoxins A, B, C, D, E, G which causes staph food poisoning
- Toxic shock syndrome toxin (TSST-1)
71
FnBP: fibronecting-binding protein (in staph aureus)
Fibronectin (body's mucosal defence proteins) solubilizes in the fridge and precipitates out when it is heated (opposite from normal). It coats our mucosal lining, it likes to occupy the same places as gram-negative rods like to bind to. So by coating our mucosal linings with fibronectin, it competes with gram negatvie. So most of our nasal mucosa is gram positive. So staph aureus not only binds to our tissues but it binds to fibronectin
72
What so superantigen exotoxins do? (Staph Aureus)
- these protein toxins have an affinity for relatively highly conserved region of the T cell receptor, the MHC class II complex. They stimulate a massive T-cell response (app. 20%, contrasted with the usual 0.01%) with outpouring T cell cytokines TNF-alpha, IL-2, and interferon-gamma.
- Exfoliatin: causes expanded staph scalded skin syndrome
- Enterotoxins A, B, C, D, E, G which causes staph food poisoning
- Toxic shock syndrome toxin (TSST-1)
73
What are the 4 major diseases associated with Staph Aureus?
1. Localized abscess: skin and soft tissue: I & D is mainstay of therapy. Bone (osteomyelitis)
2. Sepsis and acute endocarditis
3- Hospital acquired and post-influenzal pneumonia: when someone is sick, elastase is abundant and cleaves fibronectin and gram negative rods move in
4. Toxin-associated syndromes
74
What is folliculits/furunculosis?
Folliculitis is localized abscesses. Infection of the hair follicles, when they are small they are folliculitis and if they grow bigger, they are furunculosis. Most dermatologic eruptions do not occur on thick skin because there are no hair follicles (Staph aureus)
75
What are the toxin associated syndromes involved with Staph aureus?
1. Food poisoning
- Enterotoxins A to E, and G
2. Expanded Staphylococcal Scalded skin syndrome
- Ritters disease: no antibodies nor kidney function
- Classic scalded skin syndrome: proper kidney function but no antibodies
- Staphylococcal scarlet fever: antibodies and kidney function
- Bullous impetigo (blister)
3. Toxic shock syndrome
76
Who discovered the toxic shock syndrome associated with staph aureus?
James K Todd
77
Which bacteria is he talking about when he says you have to remove a tampon?
Staph aureus
78
What can a tampon cause?
Toxic shock syndrome related to staph aureus.
79
What are the symptoms associated with Toxic Shock syndrome?
- High fever
- Hypotension
- Diffuse erythema (resembling sunburn)
- Hyperemia of mucous membranes (red: eyes, lips, labia)
- Vomiting and diarrhea
- Sometimes progresses to multi-system organ failure and death
- Late superficial desquamation (peeling skin)
80
How to treat toxic shock syndrome?
- Remove the source of intoxication (drain abscess, and remove tampon)
- Agressive IV fluid replenishment
- IV immunoglobulin
- Antibiotics mainly serve to prevent recurrences
81
What does MRSA stand for?
methacylin resistant Staph Aureus
82
What does VISA stand for?
Vancomycin resistant staph aureus
83
What does CAMRSA stand for?
community acquired methacylin resistant staph aureus
84
What are the symtoms of CAMRSA?
- large soft tissue abscesses which tend to relapse
| - May cause sepsis
85
What is staphyloccus epidermidis characteristic for?
Produces slime and has affinity for prosthetic devices
86
Staphyloccus epidermis:
- Coagulase negative
- Skin commensal, opportunistic infections
- produces slime, has affinity for prosthetic devices
- Antibiotic resistant, need vancomycin
87
What is the second most common cause of UTIs in young women?
Staph saprophyticus
88
What is the most common cause of UTIs in young women?
E. coli
89
Staphylococcus saprophyticus:
- Coagulase negative
- Novobiocin resistant
- 2nd most common cause of UTI in young women
- Antibiotic susceptible
- Grow on dead things
90
Which bacteria is notorious to grow on dead things?
staph saprophyticus
91
Are streptococci aerobic or anaerobic?
aerobic, but they do not utilize oxygen
92
Characteristics of Streptococci:
- gram positive
- spherical
- aerobic (but do not use oxygen)
- Usually stain in chains
- complex nutritional requirements
- Lack of catalase enzyme
93
How is strep distinguished from staph?
By colonial morphology (small, translucent colonies often hemolytic) and by lack of catalase enzyme
94
Classification of strep:
- By hemolytic reaction (alpha, beta, alpha prime)
- By Lancefield grouping (serotyping of C carbohydrate from cell wall: A, B, C...)
- By phenotypic characteristics (biochemical tests)
95
What are the classification of Streptococcus pyogenes?
- Beta-hemolytic
- Lancefield group A
- Penicillin susceptible
96
What is beta hemolytic, Lancefield group A, and penicillin susceptible?
Streptococcus pyogenes
97
What are the virulence factors of strep pyogenes?
- Capsule: hyaluronic acid
- Fimbriae: M protein
- Protein F: fibronecting-binding protein
- Exotoxins: pyrogenic exotoxins, streptokinase, streptodornases, hyaluronidase, streptolysins O and S, and C5a peptidase
98
What is associated with M protein
Fimbriae
99
What is protein F?
fibronectin binding protein
100
What are the streptococcus pyogenes diseases?
- Acute suppurative infections (pus forming)
- Toxin-mediated syndromes
- Post-streptococcal disease (which is an unfortunate consequence of activation of our own immune systems)
101
What are the acute suppurative infections related to steptococcus pyogenes?
Pharyngitis:
- self-limited, buy potential for rheumatic fever
- Small % of pharyngitis
- Secondary to contact with a case or nasopharyngeal carrier
Skin and soft tissue infections:
- Impetigo: amber crusts
- Cellulitis: soft tissue infection, rapidly spreading
- Erysipelas: a superficial contained lymphangitis, features peau d'orange skin
- Necrotizing fascilitis, non gas forming (flesh eating disease)
Sepsis:
- puerperal sepsis, but primary sepsis is rising
- Splenectomized patients predisposed
102
What bacteria is associated with Peau d'orange?
strep pyogenes
103
What is the proper term for peau d'orange
erysipelas
104
Amongst the skin and soft tissue infections associared with strep pyogenes, which one is clearly demarcated with the eye and which one do you have to touch?
To the eye: erysipelas
| To touch: cellulitis
105
What are the step. Pyogenes toxin-mediated syndromes?
1. Scarlett fever
- Pharyngitis with erythematous skin eruption, strawberry tongue, and Pastia's lines due to pyrogenic exotoxin
2. Streptococcal Toxic shock syndrome
- Due to pyrogenic exotoxin acting as superantigen-- massive T cell activation and cytokine release
- shock and multiorgan failure
106
Which bacteria is most famously associated with Scarlett fever?
S. pyogenes, but there is a staph scarlet fever
107
Which bacteria is most famously associated with Toxic shock syndrome?
Staph aureus, but also a streptococcal toxic shock syndrome
108
What are the post-streptococcal diseases
1- Acute glomerulonephritis
- 1-3 weeks after s. pyogenes infection at any body site
- Small number of nephritogenic strains, defined by M protein, and T antigen
- Hematuria, hypertension, edema
- Excellent prognosis, but promp treatment is not preventative
2. Rheumatic fever
- 2-4 weeks after s. pyogenes pharyngitis only
- prompt treatment is preventative
- primarily due to host factors
- Fever, migratory polyarthritis, carditis, and other signs.
3. Erythema nodosum
- multiple tender nodules on anterior lower extremities and face
- many infections and drugs, not solely post-strep
109
S. pneumoniae
- Lancet-shaped diplococci
- alpha-hemolytic, no Lancefield antigen
- Normal throat flora, carried by up to half the population, depending on season
- About 20% of strains in Canada are resistant to penicillin
Autolysin: present in cell wall, causes colonies to be dime-shaped
Pneumolysin: present in cytosol, released by autolysin, and damages mammalian cell membranes
110
What are the s. pneumoniae diseases?
1. Lower respiratory tract infections: community-acquired pneumonia (most common bacterial cause), acute exacerbations of chronic bronchitis
2. Upper respiratory tract infections: the most common cause of pediatric otitis media and sinusitis, up to 50%
3. Bacterial meningitis: one of most common causes
4. Sepsis: splenectomized patients predisposed
111
Which strep is alpha-hemolytic, no lancefield antigen
S. pneumoniae and the virians group
112
Which strep is group B?
s. agalactiae
113
S. agalactiae
- Group B
- neonatal pneumonia, sepsis, and meningitis
- Carried in the vagina by 25 % of normal women, also common in throats of both sexes
- Infants can be colonized during birth, all serotypes
114
Which strep is group C?
the ones associated with horses
115
Which strep is associated with causing caries?
The viridians group
116
What is the Viridians group?
- alpha-hemolytic Streptococcus species which do not possess Lancefield antigens, not usually referring to s. pneumoniae
- Normal oral flora
- the most common cause of subacute bacterial endocarditis
- S. mutans associates with caries
117
What is the most common cause of subacute bacterial endocarditis?
The viridans group
118
What does strep in the blood suggest?
endocarditis
119
What are the 2 main classes of gram-negative rods?
1. The enteric bacteria (enterobacteriaceae)
| 2. The nonfermenters
120
What are the 4 cardinal characteristics of enterobacteriaceae?
- Ferment glucose
- Convert nitrates to nitrites
- If they have flagella, they are peritichous
- cytochrome oxidase positive
121
Enterobacteriaceae
- normal flora of the mouth, oropharynx, genitalia, distal urethra, and especially the large bowel
122
What is the shared determinant of pathogeneicity in enterobacteriaceae?
LPS: lipopolysaccharides
123
What are the components of LPS:
o antigen, core polysaccharide, and lipid A
124
What is the most common cause of UTIs?
escherichia coli (e. coli)
125
How is e. coli typed?
O antigen- LPS
H antigen- flagella
K antigen- capsule
126
What is ETEC?
enterotoxigenic E. coli
127
What is the major cause of traveler's diarrhea?
ETEC: enterotoxigenic E. coli.
128
What does enteroinvasive e.coli cause?
bloody diarrhea
129
Which E. coli strain was found in Walkerton?
verotoxigenic or enterohemorrhagic e. coli (VTEC, EHEC)
130
What does verotoxigenic and enterohemorrhagic e.coli cause?
bloody diarrhea, and hemolytic uremic syndrome
131
For which e. coli strain are antibiotics contraindicated?
verotoxigenic (enterohemorrhagic) e. coli (VTECH, EHEC)
132
Salmonella enterica ssp. enterica
- Food (esp. poultry, eggs), water, pet turtles, African dwarf frogs
133
What does salmonella enteria ssp. enterica cause?
diarrhea, extraintestinal disease, endocarditis
134
Is salmonella enterica ssp. enterica: antibiotics contraindicated?
yes
135
What causes typhus?
salmonella enterica ssp. enterica serovar. Typhi
136
What do you get when you eat or drink something fertilized with human waste?
typhus, from salmonella enterica ssp. enterica serovar. typhi.
- antibiotics indicated
137
What type of flagella does shigella species have?
- none
| - nonmotile
138
Which bacteria causes dysentery with red jelly feces?
shigella species
139
What is the species associated with cold cut contamination?
yersinia enterocolitica
140
Which enterobacteriacea is related to pseudoappendicitis?
yersinia enterocolitica
141
What caused the black death, the plague?
yersinia pestis
142
What do the squirrels in SW USA carry?
yersinia pestis
143
Which painting involves St-Sebastian praying to take the plague away?
Yersinia pestis
144
which enterobacteriaes are nonmotile?
shigella and klebsiella pneumoniae
145
Which enterobacteriae cause pneumonia in alcoholics?
Klebsiella pneumoniae
146
What is special with serratia marcescens?
blood red pigment
147
How are nonfermenters distinguished from enterobacteriaceae?
- Failure to acidify the butt of Kllgler's iron Agar (KIA) or Triple Sugar Iron Agar (TSI)
148
What are the 2 nonfermenting species?
- pseudomonas aerigunosa
- Acinetobacter anitratus
- Stenotrophomonas maltophilia
149
Pseudomonas aeruginosa
Cytochrome oxidase positive
Look green on agar plates (pyocyanin production)
Smells like grapes
Contaminate sterile solutions nosocomial
Pneumonia, UTI, wound infection, burn infections
Hot tub folliculitis
150
Which species causes ecthyma gangrenosum?
pseudomonas aeruginosa
151
What are the pseudomonas aeruginosa community acquired infections?
- Malignant otitis externa (glue ear) in diabetics
- Hot tub folliculitis
- Endocarditis in IV drug abusers
- Osteomyelitis of calcaneum after penetrating injury
152
Which nonfermenter is most likely to contaminate a sterile solution and even disinfectants?
acinetobacter species
153
Which specie caused CF camps to close?
Burkoldaria cepacia
154
Which are the catalase negative gram positive rods?
- Lactobacillus and ersipelothric rhusiopathiae
155
which species are important to maintain the acidic environement of the vagina
lactobacillus
156
Which specie is related to butchers hands and fish cleaners?
Erysopelothric rhusiopathiae
157
What cause erysipeloid?
Erysopelothrix rhusiopathiae
158
What are the catalase positive gram positive rods?
- Bacillus
- listeria monocytogenes
- Corynebacterium
159
What is the only aerobic spore former?
Bacillus
160
What causes the fried rice syndrome?
bacillus cereus
161
Describe the enterotoxins associated with bacillus cereus:
There are emetic and diarrheal enterotoxins. Emetic enterotoxin is heat stable
162
What are the medusa head colonies?
bacillus anthracis
163
What looks like ground glass type of hemolysis on blood Agar?
Listeria monocytogenes
164
Which is the species that involves a toxin that brings the specie into the brain to cause meningitis?
Listeria monocytogenes
165
How does listeria monocytogenes cause damage?
After phagocytosis by macrophages, a toxin called listeriolysin O damages the phagolysosome allowing the organisms to escape into the cytosol where they divide. They assemble actin filament tails which push the bacteria towards the cell surface and into pseudopods which contact other host cells.
166
Which specie looks like chinese symbols?
Corynebacterium
167
Which specie causes diptheria?
Corynebacterium
168
What are the complications of diptheria?
1- local necrosis: pseudomembrane in the oropharynx which can asphyxiate
2- toxin can enter the general circulation and poison the heart
169
What so anaerobes lack that makes them unable to survive in oxygen.
superoxide dismutase
170
What are some clinical clues of anaerobic infection:
- foul odour
- Infection located in proximity to mucosal surface
- Bite wounds
- Gas in tissues or discharge
- Mixed organisms seen on gram stain fail to grow in aerobic culture
171
Which infections commonly involve anaerobes vs seldom do?
DO: brain abscess, deep neck space infection, dental abscess, lung abscess, aspiration pneumonia, bronchiectasis, intraabdominal infection, wound infection floowing surgery to GI or female genital tract, diabetic foot ulcers, gas gangrene, breast abscess (especially infra areolar), and perirectal abscess.
DONT: meningitis, acute sinusitis and otitis, pharyngitis, bronchitis, acute cholecystitis, spontaneous peritonitis, urinary tract infections, acute osteomyelitis
172
What is mendelson's syndrome?
aspiration pneumonia due to aspiration of vomit.
173
What are the gram positive spore forming rods?
Clostridium
174
What are the different types of Clostridiums?
c. tetani
c. botulinum
c. perfringens
c. difficile
175
which toxin causes the spasms in tetanus
tetanospasmin
176
What is the presenting symptom in tetanus?
trismus
177
which specie looks like a tennis racquet?
clostridium tetani
178
In which case does one case consist of an outbreak?
clostridium botulinum
179
Which specie results from improper home canning and related to why kids cannot have honey?
clostridium botulinum
180
Which specie is used for Botox?
clostridium botulinum
181
which specie causes gas gangrene
clostridium perfringens
182
Who have the highest rate of carriers of c. dif?
infants under 8 months of age and hospitalized patients
183
What is the most common cause of infectious diarrhea in hospitals and long term care facilities?
C. difficile
184
Bacteroides fragilis
- bacteroides are the major anaerobes of the colon
- gram negative rods
- cause peritonitis and abdominal abscesses
- Produces beta lactamase
185
What is a gram negative diplococci?
neisseria gonorrhea
186
What is a fastidious organism?
gonorrhea: needs special enriched media and CO2
187
Is gonorrhea cytochrome oxidase positive or negative?
positive
188
What are the virulence factors of neisseria gonorrhea?
- Por A protein
- Opa proteins (mediate adherence)
- Rmp proteins
- LOS (lipo-oligosaccharide)
- pilin protein
189
Which bacteria expresses LOS (lipo-olygosaccharide)
neisseria gonorrhea
190
What are the infection syndromes associated with gonorrhea?
urethritis and cervicitis
- Arthritis dermatitis syndrome
- Monoarthritis
- Prepubescent females: vaginitis
191
what is associated with profuse purrulent discharge in males?
gonorrhea
192
What are females with gonorrhea at risk for?
pelvic inflammatory disease
193
What is Fitz-Hugh-Curtis syndrome?
It is the string adhesions under the liver (happens in females with gonorrhea when the infection spreads up from the uterus and into the fallopian tubes then out into the abdominal cavity)
194
What are the complications of gonorrhea?
- Disseminated infection
- Fitz Hugh Curtis syndrome
- Ophthalmia neonatorum
- Pelvic inflammatory disease
195
When would you treat gonorrhea?
When you know they have it, when you suspect they have it.
196
How is neisseria meningiditis spread?
not sexually, but by close contact and respiratory.
197
What is Waterhouse-Friedrichson syndrome?
Adrenal necrosis that occurs in patients with neisseria meningitidis
198
Which subgroups of neisseria meningiditis are present in Canada vs the americas?
B, C, and Y are emergent in the americas and W in Canada
199
What are the curved bacteria?
Vibrio, campylobacter and helicobacter
200
Which bacteria corkscrews there way through fluids faster than any other bacteria?
campylobacter
201
is campylobacter gram positive or negative
negative
202
Which bacteria causes explosive diarrhea?
campylobacter
203
Campylobacter
- slender spiral gram negative
- Single polar flagelum which allows them to corkscrew their way through fluids faster than any other bacteria
- Microaerophilic (likes less oxygen) and capnophilic (likes more CO2)
- Assacharolytic (doesnt break down sugars)
- Requires special selective medium
204
What is the bacteria in which wild birds form the principal reservoir for farm animals?
campylobacter
205
Where is campylobacter found?
raw or undercooked poultry, meat, fish, and shellfish. Commonly in raw milk due to fecal contamination at milking and occasionally to campylobacter mastitis
206
What is the most common cause of acute enteritis in developed countries?
campylobacter entiritis
207
What are the 2 species of campylobacter?
c. jejuni and c. coli (jejuni causes 80 to 90% of infections)
208
Which 2 bacterias can cause pseudoappendicitis?
yersinia entero. and campylobacter
209
What is the bacteria that lives in Brackish waters?
vibrio vulnificus
210
Vibrio:
- motile
- Oxidase positive
- gram negative
- Lives in brackish water
- commonly associated with seafood
- O and H antigens are present
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Vibrio cholera:
- O1 strains cause cholera, non O-1 strains cause milder diarrhea
- Contaminated drinking water
- Cholera toxin binds to GM 1 gangliodise receptors on intestional mucosa, activates cyclic AMP which inhibits sodium absorption and causes secretion of chloride
- Dehydration must be treated promptly
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What does the cholera toxin look lie?
central active (A) subunit surrounded by non-toxic pentameric binding (B) subunits.
213
Who is considered to be the father of epidemology?
John Snow
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Who discovered Cholera?
John Snow
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Where was the cholera pump located?
Broadwick and Poland, in Soho England
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Which disease involves stool that is clear as water?
Cholera
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What is the vaccine available for cholera that also protects against travellers diarrhea?
Dukoral
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If someone is swimming in salt water with an open wound, what are they especially at risk for?
vibrio vulnificus
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What are preventative measures associated with vibrio?
avoid consumption of raw shellfish, particularly by patients with liver disease and avoid swimming in salt water with open wounds
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What makes helicobacter unusual?
They colonize the stomach.
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Helicobacter:
multiple polar flagella
- colonize the stomach
- Main species is H. pyloti which has similarities to the campylobacters
- outstanding property is the production of a very potent urease which splits ammonia from urea to produce an alkaline environment in the stomach.
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What does helicobacter cause?
- Acute gastritis
- ulcers
- Associated with gastric cancer and gastric B-cell lymphoma MALTomas
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How do you treat helicobacter?
triple therapy
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What are the 3 types of spirochaetes?
treponema, borrelia, and leptospira
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Are spirochaetes gram positive or negative?
Gram negative
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Spirochaetes:
- Gram negative
- Corkscrew rods with axial flagella and outer sheath
- Flexible cell wall
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What is the bacteria related to syphilis?
treponema pallidum
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Treponema pallidum:
- Syphilis, the Great pox, the Great imitator: T. pallidum ssp. pallidum
- T. pallidum ssp. Endemicum: not sexually transmitted, it is a syphilis commonly seen in North Africa and Middle East called bejel or njovera
- T. pallidum ssp. Pertenue: yaws, frambesia tropica.
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Which Treponema is related to raspberry-like outbreaks on the skin and yaws ?
T. pallidum ssp. Pertenue
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Which treponema is not sexually transmitted and seen in Northern African countries?
T. pallidum ssp. Endemicum
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Which disease is associated with Henry the 8th?
T pallidum ssp. pallidum: syphillis
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What is the most chronic infectious disease?
treponema pallidum: syphilis
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What is the 1/3 rule in infectious diseases/
1/3 self cure
1/3 progress to tertiary
1/3 keep relapsing
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What are the primary signs of syphilis?
chancres (at site of inoculation), they are painless and go away after 3 weeks
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What are the secondary signs of syphilis?
maculopapular eruption including palms and soles, condylomata lata (warts) (6 months)
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What are the tertiary signs of syphilis?
endarteritis obliterans- gummata (lesions)(years)(when arteries plug up and cause defiguring lesions)
- Charcot's joint
- and shuffling gate
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What is the only treatment option for syphilis?
penicillin
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What is Jarisch-Herxheimer reaction?
It is an inflammatory reaction after treatment with penicillin that can be treated with advil.
239
Who discovered Syphilis?
Sir William Osler
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What is the Argile Robinson pupil?
when it can accomodate but doesnt react.
241
What is the bacteria that is associated with skin discolorations?
treponema carateum
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Treponema carateum:
- pinta: acute and chronic nonvenereal skin infection
- skin discoloration leads eventually to depigmentation
- Found only in isolated rural populations living undercrowded, unhygienic conditions in the American tropics
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Borrelia
- Highly motile spirochaetes, flagella beneath outer membrane, linear chromosome
- LINEAR CHROMOSOME
- maintained in nature by cycling through wild animals and ticks
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What are the two species associated with borrelia?
- borrelia recurrentis (lice)
| - borrelia duttonii (ticks)
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Which bacteria causes trench fever?
borrelia recurrentis
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Which bacteria is associated with lice?
borrelia recurrentis
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Borrelia recurrentis:
- Louse-borne (epidemic) relapsing fever
- Mainly in Africa, esp. Ethiopian higlands
- Fever lasting 2 to 9 days alternating with afebrile periods of 2 to 4 days
- Up to 10 relapses
- Popular during the war: battle fatigue
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Which specie is associated with lyme disease?
borrelia burgdorferi
249
What is the tick responsible for transmission of lyme disease?
Ixodes scapularis: the deer tick
250
In which stage of lyme disease do joint syndromes occur?
2nd stage
251
Lyme disease (3 stages)
1: Erythema migrans and flu-like symptoms
2: arthralgia, arthritis, meningitis, Bell's palsy, painful radiculopathy, cardiac conduction defects, and myocarditis
3: chronic arthritis and progressive CNS disease
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What is erythema migrans?
the circle like skin eruptions around a tick bite
253
What is the bacteria related to raccoon hunting?
leptospira
254
What is leptospirosis?
- Primary lesion is disruption of cell membranes of endothelial cells of small blood vessels throughout the body
- Due to glycolipoprotein toxin
- Widespread capillary leakage and petechial haemorrhage
- Worse in lungs, omentum, and pericardium.
255
What are the phases of leptospirosis?
1: 1-2 weeks: fever and malaise, decreases or disappears after 1 week.
2: aseptic meningitis, hepatitis, nephritis, conjunctivitis, IgM titre increases
256
Which one of the spiral bacteria are not true spirochaetes?
spirillum minus
257
Which bacteria is associated with rat bites?
spirillum minus
258
Spirillum minus:
- rigid cell wall
- The common form of sporadic rat-bite fever in Asia, particularly Japan
- Spirillary fever, Sodoku
- Distinctive reddish purple skin plaques
- Previously healed bite wound reactivates when symptoms appear ***
259
What is an example of an obligate intracellular bacteria?
Chlamydia
260
What is an example of energy parasites?
Chlamydia
261
Chlamydia:
- small obligate intracellular bacteria
- Unable to synthesize ATP: energy parasites: used their host's ATP
- Structurally similar to small gram negative bacteria except no peptidoglycan
- unique reproductive cycle
262
What is the unique reproductive cycle of Chlamydia?
- Intracellular form is the reticulate body
- RB divides repeatedly by binary fission 48h until a large cytoplasmic inclusion is formed
- RB's condense to form elementary bodies which are released into the environment by lysis of the host cell
- EB's are phagocytosed by different susceptible host cells
- EB prevents fusion to phagosome and lysosome
- The EB reorganizes into the larger RB
EB: elementary bodies
RB: reticulate bodies
263
What are the chlamydia species?'
- Chlamydia trachomatis
- Chlamydia psittaci
- Chlamydophila pneumoniae
264
Chlamydia trachomatis:
- Inclusion bodies stain with iodine
- 2 groups of serovars that cause different syndromes:
- - A to L - trachoma biovar. ( D to K) commonly cause genital tract infections in North America and Europe
- - L1, L2, L2a, L3 -- lymphogranuloma venereum biovar
265
What is the leading cause of blindness in developing countries
trachoma
266
What is trachoma?
Chronic infection of chlamydia trochamatis leads to scarring and trichiasis. It is the leading cause of blindness in developing countries.
Serovars: A, B, Ba, and C
267
What are non-gonococcal urethritis/cervicitis?
- Serotypes D - - K
- Most common cause of NGU, especially in college students
- Females are often asymptomatic by at risk for PID which leads to infertility and chronic pelvic pain
- neonates born to infected mothers at risk for inclusion conjunctivitis, occasionally infant pneumonia
268
What is lymphogranuloma venereum?
- symptom of chlamydia
- Serovars L1, L2, L2a, and L#
- uncommon in north america and europe
- transient papules on external genitalia followed in 1-2 months with painful inguinal and perirectal lymphadenopathy
- Groove sign
269
What is groove sign associated with ?
lymphogranuloma venereum (chlamydia trachomatis)
270
What causes chlamydia psittaci?
- transmitted by inhalation of dust contaminated with feces or respiratory secretions of infected birds (history)
- Pneumonia often associated with headache and splenomegaly
Parrot-like birds
271
Chlamydophila pneumoniae
- CA pneumonia, brinchitis, sinusitis
- Person to person transmission
- common, but seldom diagnosed due to poor availability of reagents
- tantalizing associations of high antibody titres with coronary atherosclerosis and asthma trials
272
What is the smallest free living organism>
mycoplasma
273
Mycoplasma:
- smallest free living organism
- trilaminar outer membrane, stains well with Giemsa but not with Gram
- no cell walls: resistant to cell wall attacking antibiotics (beta-lactams)
- Cell membrane contains sterols, which must be in growth medium
- Slow growing
274
What are the characteristics of mycoplasma?
- Ubiquitous: found everywhere
- Frequently contaminate tissue cultures
- Pass through filters designed to trap bacteria
- related to the clostridia
275
Disease associations
pneumonia: M. pneumoniae
Non gonecoccal urithritis (NGU): M. genitalium
Postpartum fever: M. hominis and U. urealyticum
Arthristis in immunosuppressed and hypogammaglobulinemic: M. hominis and u. urealyticum
Misc. in immunosuppressed: M. hominis
276
What is the second most common cause of community acquired pneumonia
Mycoplasma pneumoniae
277
What is the leading cause of community acquired pneumonia
Strep pneumoniae
278
Which pneumonia causing bacteria is related to summer outbreaks every 3 to 4 years?
M. Pneumoniae
279
What are the clinical features of M. pneumoniae?
Chest x-ray looks worse than you would expect
- anorexia, nausea, vomiting, diarrhea
- musculoskeletal: myalgia, diarrhea
- Erythema multiforme
- transient hemolytic anemia
- Meningoencephalitis (70% of hospitalized)
- Relapses, persistent cough
280
What is the second most common cause of NGU after chlamydia trachomatis?
M. genitalium
281
Which bacteria is associated with AIDS
mycoplasmas: fermentans, penetrans, and pirum
282
Ureaplasma urealyticum
- genital commensal; sexual transmission
- Very small colonies; splits urea
- Established roles in postpartum fever and arthritis in immunosupressed and hypogammaglobulinemic patients
- Moderate evidence for causality: NGU, infection stones, pneumonia
