COMMON BACTERIAL PATHOGENS 2 Flashcards
most common g+ rods in human disease
clostridium
clostridium family - how do they respond to oxygen
STRICT anaerobes- get killed by molecular oxygen
do clostridium family members make spores
yup
C diff typically presents as
hospital acquired GI infection after normal flora is depleted via antibiotics
3 clostridium dificile virulence factors
- spores that are not killed by alcohol based hand sanitizers and enterotoxin and potent cytotoxin
how do you diagnose C diff
ELISA for toxin in stool, culture from stool (but then you have to prove that the culture from stool produced the toxin) or PCR
although most antibiotics have been implicated in C difficult resistance but the firs tone was
clindamycin
clostridia most likely to be encountered in a hospital
difficile
how does clostridium tetani normally present
local infection leads to toxin production in anaerobic areas that lead to retrograde axonal transport to CNS and causes SPASTIC PARALYSIS
2 clostridium tetani viruelnce factors
spores and txins
2 vaccines for tetanus
inactive toxoid or tetanus human IgG
clostridium tetani is a common organism where
soil and GI tract of animals SPORESSS
clostridium botulinum toxin- how does it work and what does it cause
blocks ACh transmission in neuromuscular junctions and causes flaccid paralysis
2 presentations of clostridium perfringens
wound infections and food poisoning
food poisoning caused by a toxin produced iN VIVO is caused by
clostridium perfringens
what kind of injuries lead to clostridium perfringins wound infections
crush injuries or anything that causes reduced blood flow and a low oxygen environment
what toxin does clostridium perfringens produce in wound infections and what does it do
alpha toxin (phospholipase enzyme) that kills phagocytes and muscle tissue
food poisoning with C. perfringens - what toxin does it secrete and what doe sit do
enterotoxin– disrupts tight junctions between endothelial cells in ilium leading to dysregulated fluid transport
prototypical G negative bacteria
e coli
ETEC
enterotoxigenic E coli causes travelers diarrhea
how to treat ETEC
self limiting usually only need fluids
3 ways that e coli infections show
GI disease, UTIs, abdominal infections
UTIs infections are usually from where
endogenous from GI tract
3 scenarios that can lead to e coli abdominal infections
surgical wounds, traumatic wounds, colon cancer
how do e coli abdominal infections present usually
as an anaerobic abscess of mixed bacteria
virulence factors of e coli in GI disease
adherence to mucosal via pili and toxins disrupt electorlyte balance in gut cells
3 properties of e coli that you see in UTIs
adherence to bladder epithelium, specific interactions with bladder epithelium, and beta hemolytic
most common organism to get resistance through plasmids
e coli
where is e coli normally
intestine
3 kinds of disease caused by psuedomonas aeruginosa
- infections of trauma, surgical wounds and BURNS (opportunistic), 2. chronic lung infection in CF patients, 3. hospital acquired UTIs, pneumonias and IV catheters
difference between pseudomonas aeruginosa infections in CF patients early in life vs later
early- common infection but treated with antimicrobials, later you get a chronic infection because of intrinsic resistance
virulence factors of pseudomonas aeruginosa
bacteria are protected from phagocytosis because of viscous lung secretions, mucoid expolysaccharide, and bacterial toxin secretion
age that CF patients get chronically infected with pseudomonas
15-20
frequent cause of death in CF patietns
pseudomonas aeruginosa
if a hospitalized patient gets a new infection, think of this
PSEUDOMONAS AERUGINOSA
