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Flashcards in Bacteriology 2 Deck (20):
1

Neisseria - Both Species

Gram - Diplococci
Metabolize glucose
Produce IgA proteases
Contain LOS (lipoologosaccharides with strong endotoxin activity)

meningococcal also ferments maltose

2

Gonococci vs Meningococci

Polysaccharide Capsule?
Carbohydrate fermentation
transmission?
ppx?
tx?

sx p/w?

GC - no polyssacharide capsule MC - polysaccharide
GC - glucose only MC - glucose & maltose
GC - STI, perinatally MC - resp/oral secretions
GC - condoms, erythromycin eye ointment of newborns (prevents blindness)
MC - close contacts: Rifampin, ciprofloxacine, or ceftriaxone

GC - ceftriaxone (+azithro/doxy for CT)
MC - ceftriaxone or PCN G

GC p/w gonnorhea (purulent vaginal/penile d/c), PID, Fitz-Hugh-Curtis syndrome septic arthritis, neonatal conjunctivitis (2-5 day of life)

MC p/w meningitis, petechia, gangrene of toes, Waterhouse-Friderichsen syndome (adrenal hemorrhage => fever, AI, DIC, shock)

3

Haemophilus influenzae

morphology?
transmission?
virulence factor?
growth on what medium?

p/w?
non-typeable/nonencapsulated type p/w?

tx
ppx

Gram - coccobacilli
aerosol transmission
produces IgA protease

Culture on chocolate agar (factors V - NAD+ & X - hematin) or with s.aureus (produces NAD+ via hemolysis)

p/w epiglottitis (thumb sign), meningitis, otitis media, PNA
non-typeable most common cause of otitis media, conjunctivitis, bronchitis)

tx - mucosal infxn - amoxacilin or augmentin
meningitis - cetriaxone

ppx - close contacts with rifampin

4

Bordetella pertussis
morphology
virulence factor
p/w three clincal stages
ppx

anaerobic G- coccobacillus
3 virulence factors:
- pertussis toxin - diables Gi
- adenylate cyclase toxin - increases cAMP
- tracheal cytotoxin

3 clinical stages
- catarrhal - low grade fever, coryza (stuffed nose)
- paroxysmal - paroxysms of intense cough, inspiratory whoop, & posstussive vomitting can occur
- convalescent - gradual recovery from chronic cough

ppx: Tdap & DTaP vaccines

5

Legionella pneumophila

morphology
transmission
growth medium?
dx
tx

Legionnaires' Disease?
Pontiac Fever?

G- rod, silver stain
aerosol from environmental water source (A/C, H20 tank)
charcoal yeast extract w/ Fe and Cysteine
urine antigen, may see hypoNa

Legionnaires' Dx
- severe PNA, often u/l & lobar
- GI sx
- fever & CNS sx

Pontiac Fever - mild flu-like syndrome

6

Pseudomonas aeruginosa
morphology, oxidase?
virulence factors - PEEP + ?
p/w PSEUDOMONAS
tx - CAMPFIRE

aerobic, motile G- rod
oxidase +

virulence factors - PEEP + ROS
P - phospholipase C (degrade cell membrane)
E - endotoxin ( fever, shock)
E - exotoxin A (inhibit EF2)
P - pigments - Blue-green (pyoverdine, pyocyanin)

p/w
P - pneumonia
S - sepsis
E - ecthyma gangrenosum (necrotic cutaneous lesion, rapidly progressive, a/w immunocompromised)
U - UTI
D - DM
O - osteomyelitis
M - mucoid polysaccharide capsule => chronic PNA in CF pts 2/2 biofilm formation
O - otitis externa ("swimmer's ear")
N - nosocomial infxn (ie indwelling catheters)
A - addicts - drugs
S - skin infxn - esp burn victims, hot tub folliculitis

tx - CAMPFIRE
C - carbapenems
A - aminoglycosides
M - monobactamcs
P - polymyxins (colistin, polymyxin b)
F - floroquinolones
IR- 3rd & 4th gen cephalosporins (ceftazidime, cefepime)
E - extended spectrum PCN - piperacillin, ticacillin


7

Salmonella typhi
morphology, oxidase?
growth medium
invasion of GI tract how?

transmission & reservoir
H2S production
Flagella
Virulence factor
Infxn Dose
Effector of Abx on fecal excretion
Immune response
GI manifestation
Vaccine

Unique Properties (2)


Gram - rod, oxidase -
non-lactose fermenting - not pink on Mcconkey
M cells of peyer's patches


human only, hematogenous dissemination
yes, H2S
yes, flagella
endotoxin, Vi capsule
High (requires high numbers to cause infxn, inactivated by
gastric acid)
abx prolong infxn
monocytes
constipation ---> diarrhea
PO vaccine - live attenuated; IM vaccine - Vi capsule

1) Causes Yellow Fever:
- fever, abd pain, constipation, rose spots on abd
- tx CTX or floroquinolone

2) Carrier state with GB colonization

8

Salmonella spp except typhi
morphology, oxidase?
growth medium
invasion of GI tract how?

transmission & reservoir
H2S production
Flagella
Virulence factor
Infxn Dose
Effector of Abx on fecal excretion
Immune response
GI manifestation
Vaccine

Unique Properties (1)

G - rod, oxidase -
non-lactose fermentin ( no pink McConkey agar)
invades M cells in peyer's patches

humans & animals (pets, turtles, poultry, eggs); hematogenous spread

yes H2S
yes, flagella
Endotoxin
High
Abx prolong infxn, not indicated
mostly polymorphic neutrophils
diarrhea, sometimes bloody
no vaccine

1) common cause of gastroenteritis

9

Shigella
morphology, oxidase?
growth medium
invasion of GI tract how?

transmission & reservoir
H2S production
Flagella
Virulence factor
Infxn Dose
Effector of Abx on fecal excretion
Immune response
GI manifestation
Vaccine

Unique Properties
4f's
most severe:

G - rod, oxidase -
non-lactose fermenting - no pink on macconkey agar
invades M cells in peyer's patches - key for pathogenicity (little bugs can cause big dx with lottsa toxin)

humans only; hematogenous spread
no H2S
no flagella
endotoxin, shiga toxin/enterotoxin
low
abx shorten duration
PMN
bloody diarrhea (bacillary dysentary)
no vaccine

fingers, flies, food, feces

S dysenteriae > S flexneri > S boydii > S sonnei

10

Yersina enterocolitica

morphology
transmission
p/w

G- rod
pet feces, contaminated milk, pork
diarrhea, pseudoappendicitis (RLQ pain 2/2 ileitis or mesenteric adenitis)

11

Lactose Fermenting Enteric Bacteria
MacConkey - MacConKEE'S

MacConKEE'S:
C - citrobacter
K - klebsiella
E - enterobacter
E - E.coli (beta-galactosidase)
S - serratia

12

E coli

Morphology
Virulence Factor & their consequence (2)

G - rod, lactose fermenting

fimbriae/P-pili - cytitis, pyelonephritis
K capsule - PNA, neonatal meningitis
LPS endotoxin - septic shock

13

EIEC
Enteroinvasive E. coli

microbe invades intestinal mucosa & causes necrosis and inflammation
p/w dysentery

14

ETEC
Enterotoxigenic E.coli

produces heat-labile and heat-stable enterotoxins
p/w Traveler's (watery) diarrhea

15

EPEC
Enterpathogenic E.coli

adheres to apical surface, flattens villi, & prevents absorption
p/w diarrhea in children

16

EHEC
Enterohemorrhagic E.coli

O157:H7
Hemorrhagic Dysentery (toxin-->necrosis & inflammation), Hamburgers (uncooked & raw leafy vegetables) - transmission
Hemolytic-Uremic Syndrome
- p/w triad of anemia, thrombocytopenia & acute renal failure 2/2 microthrombi
- microangiopathic hemolytic anemia

17

Klebsiella
morphology
capsule
p/w

G- rod
polysaccharide capsule --> mucoid colonies

lobar aspiration pneumonia in DM and ETOHics and currant red sputum
abscesses in liver & lungs
nosocomial UTI

18

Campylobacter jejuni
Morphology
oxidase
preferred temperature
transmission
p/w
can be c/b (2)

G - comma, polar flagella,
oxidase +
grows 42C

F/O, pets, uncooked meat/poultry, unpasteurized milk
bloody diarrhea esp in children

reactive arthritis, GBS

19

Vibrio cholerae
Morphology
Oxidase
growth media
where found?
virulence factor
inoculation dose
acid labile or stabile?
transmission
p/w
tx

G - comma, flagella
oxidase +
growth alkaline media
endemic to developing countries
enterotoxin - permanently activates Gs (increased cAMP)
high inoculation dose
acid labile
water, raw shellfish
rice water diarrhea
oral rehydration

20

Helicobacter pylori
morphology
oxidase, catalase, urease ?
virulence
where does it colonize?
p/w
RF for what?
Tx - triple therapy

G - curve flagellated
oxidase + catalase + urease +
urease produces ammonia, alkalizing gastic environment
antrum of stomach
gastritis, peptic ulcers esp duodenal
RF for MALT lymphoma, gastric adenoCA, and PUD
triple therapy: PPI, clarithromycin, amoxacillin (metronidazole if PCN allergy)