entero part 2

Cards (127)

  • Citrobacter
    Genus of bacteria
  • Citrobacter species
    • 12 species
  • Citrobacter
    • Normal gastrointestinal flora
    • Most common species: C. freundii, C. koseri, and C. braakii
  • Citrobacter transmission
    • Person-to-person
    • Nosocomial
  • Citrobacter virulence factors
    • Endotoxin
    • Capsule
    • Adhesion proteins
    • AmpC genes (for C. freundii, resistance to ampicillin and 1st Gen cephalosporins)
  • C. freundii
    • More of an extraintestinal pathogen
    • Can cause endocarditis in IV drug abuser
  • C. koseri
    • Can cause nursery outbreaks of neonatal meningitis and brain abscess
  • C. braakii
    • Rare human pathogen associated with community-acquired infections including septicemia in a patient with cervical cancer
  • Citrobacter freundii resembles Salmonella because 80% produce hydrogen sulfide and 50% fail to ferment lactose
  • Laboratory diagnosis of Citrobacter
    • Hydrolyze urea slowly
    • Late lactose fermenter (CHYSSS)
    • All species grow on Simmons citrate medium
    • Methyl red: positive
    • Resembles Salmonella
  • Cronobacter
    (formerly Enterobacter)
  • Cronobacter species
    • 7 species
  • Cronobacter habitat
    • Normal gastrointestinal flora
    • Powdered infant formula (since di agad natutuyo)
  • Cronobacter transmission

    • Person-to-person
    • Ingestion
  • Cronobacter virulence factors
    • AmpC chromosomal betalactamase - resistance to ampicillin, and 1G and 2G cephalosporins (mutation shall result to overproduction of beta lactamase leading to resistance to 3G cephalosphorin)
  • C. sakazaki
    • Can cause neonatal infection such as bacteremia, meningitis and necrotizing colitis
  • C. maloniticus
    • Can cause adult infection
  • Edwardsiella
    Genus of bacteria
  • Edwardsiella species
    • 3 species; H: 1 only
  • Edwardsiella habitat
    • Water harboring fish and turtles
    • Commonly cold- and warm-blooded animals
  • Edwardsiella transmission

    • Endogenous
    • Nosocomial
  • E. tarda
    • Rarely encountered unless immunocompromised
    • Can cause wound infection called myonecrosis, gastroenteritis, septicemia, meningitis, and systemic infection if with underlying liver disease
  • E. hoshinae
    • Found in snakes, birds, and water
  • E. ictaluri

    • Causes enteric septicemia in fish
  • Myonecrosis
    Also called infarction of skeletal muscle, occurs when the blood supply is inadequate to maintain muscle viability
  • Edwardsiella laboratory diagnosis
    • Culture: MAC - clear and colorless
    • Biochemical test: Urease (-), LDC (+), H2S (+) - black PECS, Indole (+) - Mor PECPEK Ples
  • Enterobacter
    Genus of bacteria
  • Enterobacter species
    • 12 species
  • Enterobacter habitat
    • Normal gastrointestinal flora, water, food and vegetables (common in farmers)
  • Enterobacter transmission
    • Endogenous
    • Nosocomial
  • Enterobacter virulence factors
    • Endotoxin
    • Capsule
    • Adhesion proteins
    • Plasmids - resistance to multiple antimicrobial agents
  • E. cloacae
    • Most commonly isolated
    • Causes UTI, respiratory tract and wound infections
    • Listed in the top 10 commonly isolated healthcare-associated infections
  • Enterobacter laboratory diagnosis
    • Motile
    • Rapid lactose fermenter
    • Produces mucoid colony
    • Urease (-) except E. gervoiae
  • Escherichia coli
    Genus of bacteria
  • E. coli species
    • 6 species
  • E. coli habitats
    • Diarrheagenic or intestinal: STEC, ETEC, EPEC, EIEC, EAEC
    • Extraintestinal: UPEC, MNEC
    • 80% have K1 antigen
  • E. coli transmission
    • Fecal-oral route or consumption of undercooked beef or milk from colonized cattle (depending on strain)
    • Endogenous
  • Escherichia coli is the leading cause of UTI, along with Staphylococcus saprophyticus
  • E. coli is used as an indicator of fecal contamination of water
  • UPEC virulence factors
    • Pili: for adherence to cells
    • Cytolysins: inhibit immune effector cells
    • Aerobactin: chelate iron
    • Capsule production