ESCHERICHIA Flashcards
What kind of pathogen is Escherichia (E.coli)?
Bacteria
Is Escherichia (E.coli) gram positive or gram negative?
Gram negative
What would Escherichia (E.coli) look like on a microscope slide?
Pink rods
Is Escherichia (E.coli) aerobic or anaerobic? Does it form spores?
Aerobic
It does not form spores
What is the significance of Escherichia (E.coli) being a motile bacteria?
The bacteria can move on its own, escape unfavorable conditions and exploit new areas where it can survive and continue to be pathogenic
What are some strains of Escherichia (E.coli)?
-Enterinopathogenic E. coli (EPEC)
-Enteroinvasive E. coli (EIEC)
-Enterotoxigenic E.coli (ETEC)
-Enteroaggretive E. coli (EAEC)
-Shiga toxin producing E. coli (STEC)
PITAS like pita bread :)
P-athogenic
I-nvasive
T-oxigenic
A-ggretive
S-higa toxin
Regular E.coli: normally found in gut flora
How is ETEC transmitted?
-Food and water borne
What is the pathogenesis of ETEC?
Enterotoxins
How would an ETEC infection present?
Traveler’s diarrhea
How is STEC transmitted?
-Food and water bornre
-Person to person
-Animals
What is the pathogenesis of STEC?
-Shiga toxin
*Strain 0157:H7 from restaurants!
How would a STEC infection present?
Hemolyti urea syndrome: Fever, Thrombocytopenia (low platelet count), Possible renal Failure
-Hemorrhagic colitis: severe cramping, initially diarrhea is watery and then grossly bloody
How is EPEC transmitted?
Person to person
What is the pathogenesis of EPEC?
Bacteria adheres to intestinal lining (forms adhesions) will cause intestinal leaking (malabsorption)
How does a EPEC infection present?
Watery diarrhea
How is EIEC tansmitted?
-Food and water borne
-Person to person
-Travelers
What is the pathogenesis of EIEC?
DIRECT INVASION of colon cells
How would an EIEC infection present?
Dysentery syndrome similar to Shigella bacteria
-Colitis (inflamed colon)
-Inflammation
How is EAEC tansmitted?
-Food and water borne
-Person to person
-Travelers
What is the pathogenesis of EAEC?
Diffuse aderence and replication, yet not invasive (doesn’t normally spread)
How would an EAEC infection present?
-Travelers diarrhea
-Persistent diarrhea
-Symptoms can last MONTHS
Due to the wide spectrum of the disease, numerous strains of E.coli may also cause what infections?
-UTI (most common in women)
-Diarrheal illness
-Intra-abdominal infection
-Neonatal meningitis
-Bacteremia
-Hospital acquired (nosocomial) pneumonia
-Surgical wound infections
What is the treatment for infections caused by these strains of E.coli? What does it depend on?
Depends on severity/symptoms of infection
-Usually self limiting/will resolve on its own:
Hydration, supportive and symptomatic treatment
-Severe non-bloody diarrhea: Ciprofloxacin, Bactrim, Rixaximin
-Bloody diarrhea: NO ANTIBIOTICS, this will make it worse
What two E.coli types can cause travelers diarrhea?
ETEC and EAEC
(Think: TA = time of arrival, vacation, traveling!)
What kind of infection would be caused by normal gut flora E.coli?
Hospital acquired (nosocomial) Pneumonia: association with being on a vent, common in nursing homes and hospitals
Neonatal meningitis: highest risk in first month of life (along with Group B strep)
UTI (spectrum):
-uncomplicated healthy patients (98%)
-Kidney infection (pyelonephritis), catheter associated, urosepsis: tachy or low BP, shock syndrome symptoms (2%)
Intra-abdominal infections: Any barriers of organs, if disrupted, can be affected
-intraperitoneal abcess (collection of pus in abdomen)
-Peritonitits: inflammation of lining in abdomen (usually during a surgery)
How can a normal gut flora E.coli UTI be treated?
-Macrobid, Bactrim, Quinolones
-3rd generation Cephalosporins for complicated cystitis
How can a normal gut flora E.coli pyelonephritis infection be treated?
IV Ceftriaxone, Ciprofloxacin, Bactrim
***MACROBID WILL NOT WORK
How can a normal gut flora E.coli Intra-abdominal infection be treated?
-3rd/4th gen Cephalosporins
-Quinolones
-Ceftriaxone (Zosyn)
What does normal gut flora E.coli have an increasing resistance to?
UNASYN (ampicillin and sulbactam combo)
