M5 PART 4 Flashcards
- the most common form of enterococcal infections
- frequently associated with indwelling catheters, instrumentation, or structural abnormalities of the genitourinary tract
UTI
Enterobacteriaceae
MOTILITY
motile w/ peritrichous flagella or nonmotile
Enterobacteriaceae
oxygen requirement
facultative anaerobes
Enterobacteriaceae
grow well on what medium
MacConkey agar
Enterobacteriaceae
____ fermenters, often with gas production
glucose
Enterobacteriaceae
reduce ____ to ____
nitrate to nitrite
Enterobacteriaceae
catalase ____
oxidase ____
catalase positive
oxidase negative
- Gram-negative rods
- Either motile with peritrichous flagella or nonmotile
- Grow on peptone or meat extract media without the addition of sodium chloride or other supplements;
- Grow well on MacConkey agar;
- Grow aerobically and anaerobically (are facultative anaerobes);
- Ferment rather than oxidize glucose, often with gas production
- Are catalase positive, oxidase negative
- Reduce nitrate to nitrite
Enterobacteriaceae
Enterobacteriaceae
LACTOSE FERMENTED RAPIDLY
Klebsiella
Escherichia coli
Enterobacter aerogenes & cloacae
KEE
Enterobacteriaceae | ANTIGENIC STRUCTURE
most external part of the CELL WALL lipopolysaccharide and consist of repeating units of polysaccharide, resistant to heat and alcohol and usually are detected by bacterial agglutination
O antigen
Enterobacteriaceae | ANTIGENIC STRUCTURE
- external to O antigens on some but not all Enterobacteriaceae, “Kapsule”
- may be associated with virulencce
K antigens
Enterobacteriaceae | ANTIGENIC STRUCTURE
located on flagella and are denatured or removed by heat or alcohol
H antigens
The most frequent sites of clinically important infection are the urinary tract, biliary tract, and other sites in the abdominal cavity, but any anatomic site (e.g., bloodstream, prostate gland, lung, bone, and meninges) can be the site of disease.
Escherichia coli
Escherichia coli
____ inhibits adhesion of E. coli to the urothelium
cranberry juice
Escherichia coli
Infection in kidney
cystitis
- the most common cause of UTI
- accounts for 90% of first UTI in young women
Escherichia coli
Escherichia coli
____ may be highly susceptible to E. coli sepsis because they lack IgM antibodies
newborns
Escherichia coli
Newborns may be highly susceptible to E. coli sepsis because they lack ____ antibodies
IgM
Escherichia coli
Sepsis may occur ____ to urinary tract infection
secondary
Escherichia coli
E. coli and group B streptococci are the leading causes of ____ in infants.
meningitis
Escherichia coli
Approximately 80% of E. coli from meningitis cases have the ____
K1 antigen
E. COLI ASSOCIATED DIARRHEAL DISEASES
- EPEC adhesion factor (EAF) and chromosomal locus of enterocyte effacement (LEC) promote tight adherence to the intestine
- Severe, watery diarrhea, vomiting and fever in infants
Enteropathogenic
E. coli
E. COLI ASSOCIATED DIARRHEAL DISEASES
- ETEC colonization factors (pili known as colonization factor antigens [CFA]) that allows attachment to small intestine
- Traveler’s disease, diarrhea in children
Enterotoxigenic
E. coli
E. COLI ASSOCIATED DIARRHEAL DISEASES
- Produces two antigenic forms of toxins: Shiga-like toxin 1 and 2
- Mild non-bloody diarrhea, hemorrhagic colitis (bloody diarrhea), severe form of diarrhea, hemolytic uremic syndrome (a disease resulting to acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia)
Shiga toxin-producing
E. coli
E. COLI ASSOCIATED DIARRHEAL DISEASES
- Invades and destroy the mucosal cells of the colon
- Shigellosis-like, occurs in children in developing countries and in travelers to these countries
Enteroinvasive
E. coli
E. COLI ASSOCIATED DIARRHEAL DISEASES
- They are characterized by their specific patterns of adherence to human cells. This group of diarrheagenic E. coli is quite heterogeneous, and the exact pathogenic mechanisms are still not completely elucidated.
- Acute and chronic diarrhea (>14 days in duration) in persons in developing countries, cause of foodborne illnesses in industrialized countries and have been associated with traveler’s diarrhea and persistent diarrhea in patients with HIV
Enteroaggregative
E. coli
Escherichia coli | TREATMENT
CYSTITIS
TMP-SMZ or nitrofurantoin
Escherichia coli | TREATMENT
PYELONEPHRITIS
ciprofloxacin or ceftriaxone
Escherichia coli | TREATMENT
SEPSIS
3rd gen cephalosporins with or without aminoglycosides
Escherichia coli | TREATMENT
NEONATAL MENINGITIS
ampicillin and cefotaxime
Klebsiella pneumoniae
Has a very large polysaccharide ____
capsule
Klebsiella pneumoniae
Produce a lobar ____ with thick, mucoid, blood sputum
pneumonia
Klebsiella pneumoniae
mucoid sputum is also called
currant jelly
- found outside the enetric rod
- has K1 antigen (K - kapsular antigen)
- rapid lactose former
- produce lobar pneumonia
- produce mucoid sputum (currant jelly)
KLEBSIELLA PNEUMONIAE
ENTEROBACTER
may cause ____ infections
nosocomial
- E. cloacae complex and E. aerogenes
- found in soil, water, sewage system
- common cause of nosocomial infections (hospital acquired infections)
- known to be resistance because of the** β-lactamase** called ampC
- rapid lactose former
ENTEROBACTER
ENTEROBACTER
known to be resistant to ampicillin first- and 2nd gen cephalosporins because of the ____
β-lactamase called ampC
Serratia marcescens
produce a red pigment called
PRODIGIOSIN
Serratia marcescens
site of infection
urinary tract
Serratia marcescens
drug resistant because of
ampC β-lactamase
- produce a characteristic red pigment (prodigiosin)
- Most common sites of infection include the urinary tract
- resistant to penicillin, ampicillin, and first-generation cephalosporins because it harbors an inducible, chromosomal AmpC ß-lactamase
SERRATIA MARCESCENS
Proteus
motility
swarming motility
- Exhibit swarming motility
- Urease positive → stone formation (struvite)
- P. mirabilis & P. vulgaris
PROTEUS
Proteus
- urinary tract infections
- bloodstream infection (frequently secondary due to a UTI)
- respiratory tract infections
P. mirabilis
Proteus
urease ____
positive
Proteus
- wound and soft tissue infections
P. vulgaris
Morganella morganii
typically resistant to ____
penicillin
- Cause of UTI and wound infections in the hospital
- Drug-resistant (penicillin, cephalosporins)
Morganella morganii
Providencia
associated with ____
UTI
- can cause urinary tract infections, sepsis, respiratory tract infections, intraabdominal infections, and wound infections, principally among immunocompromised and/or debilitated hospitalized patients
- Citrate test: Citrate positive
CITROBACTER
CITROBACTER
can cause urinary tract infections, sepsis, respiratory tract infections, intraabdominal infections, and wound infections, principally among ____ and/or debilitated hospitalized patients
immunocompromised
Enterobacteriaceae species TREATMENT
No single therapy is available
Sulfonamides, ampicillin, cephalosporins, fluroquinolones, and aminoglycosides
Shigellae
antigen present
somatic O antigen
Shigellae
can cause the most severe human infection
Shigella dysenteriae
Shigellae
have a very low ____
infective dose
highly communicable
Shigellae
incubation period
1 - 4 days
Shigellae
infections are almost always limited to ____
gastrointestinal tract
Shigellae
toxin produced
shiga toxin