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Flashcards in Gram Neg DSA Deck (16):
1

Enterobacteriacae characteristics, Virulence factors

Gram Neg bacilli, motile except some

Catalase (+), FERMENTS GLUCOSE

Enterobacterial common antigen= core ploysac antigen in nearly all.

Virulence: have some pilli for adhesion and sex
LPS endotoxins.


2

Coliforms are a subgroup of Enterobacteriacae, what is special about them?

Which are they?

FERMENT LACTOSE

Pink to purple on MacConkey agar.

Escherichia, Klebsiellia, enterobacter, citrobacter,

3

Escherichia characteristics and virulence

Gram (-) bacilli, most are motile
Glucose and Lactose fermenters

virulence: adhesion by common pilli, ST heat stable and LT heat labile
K capsular antigens, K1 antigen- neonatal meningitis

4

Escherichia Colli disease, dx and rx

UTI by fecal contamination
Sepsis
Neonatal meningitis
Pathogenic diarrhea

dx: culture in blood media or Mcconkey, shiga toxin assay

Rx: antibiotics

5

Escherichia coli antigens

enterotoxigenic, enteropathogenic, enteroinvasive, enterohemmoragic

enterotoxigenic: travlers diarrhea
Enteropathogenic: infantilie diarrhea, salmonella-like
Enteroinvasive ( shigella-like): shigella like diarrhea, bloody
Enterohemmoragic: hemmorhagic colitis, bloody stool

6

Klebsiella

Coliform, gram - bacilli
GLUCOSE and LACTOSE fermenters

Dx: blood smears pcr
Rx: antibiotics

7

Which are lactose fermenters?

Klebsiella, escherichia, coliform subgroups

8

K. pneumoniae

hemorrhagic pneumonia with red currant jelly. most common cause of nosocomial respiratory infections
wound and soft tissue infections

9

K oxytoca

colitis, sepsis, wound and soft tissue infection

10

K granulomatis

Donovan bodies in mos in smears
Granuloma inguinal with painless genital ulcers

11

ENTERobacter

Common pathogens

Rx:

Coliform, ferment lactose, gram neg bacilii

Virulence: B lactamases

Lactose fermenter

pathogens: enterobacter cloacae & e. Gerogens

Rx: antibiotics, CANNOT use B lactamases, even if sensitivity shows it's sensitive.

12

Citrobacter

Pathogen:

Rx:

Cloriform, Lactose fermenter

B lactamase production, LPS endotoxin,

Pathogens: citrobacteria koeseri

Rx: antibiotics

13

Salmonella enterica group characteristics

Dx:
Rx:

H2S (rotten egg smell), Vi capsular antigen, Faculative intracellular parasite

Dx: culture in Hektoen enteric agar (demonstrates no lactose fermentation but + h2S fermentation

Rx: antibiotics

14

Salmonella enterica enterica, serovar Enteritidis

serovar Typhi

Entertidis: eating contaminated food. activate adenylate cyclase= diarrhea. Produce toxins in mucosa

serovar Typhi: Enteric (typhoid) fever, can mimic apendicitis

15

Shigella

Dysentaria

Non cloriform gram -

acid tolerance, invasion proteins

DX: Hectoen (negative lactose and H2S)
Rx:oral rehydration

Dysentaria: enteroinvasive dysentery, cramps and watery bloody diarrhea. Shiga toxins inhibits ribosomes

16

Yersinia

bipolar staining coccobacilli, Noncoliform