Bacteria: Gram Negative Bacilli - Enteric Tract Flashcards
List the gram negative bacilli in the enteric tract
- Klebsiella Pnuemoniae
- Enterobacter spp
- Serratia Marcescens
- Salmonella Enteritidis
- Salmonella Typhi
- Shigella
- Escherichia Coli
- Yersinia Enterocoliticia
- Yersinia Pestis
- Camplyobacter Jejuni
- Vibrio Spp
- Helicobacter pylori
- Pseudomonas Aeruginosa
- Proteus Mirabilis
Enterobacter spp., Serratia marcescens, and Klebsiella pneumoniae bacteria
- gram-negative bacillus
- can cause pneumonia
- are common causes of UTIs
- are common nosocomial pathogens
- commonly exhibit multi drug resistance
- lactose fermenting bacteria
- form pink colonies on MacConkey agar
Enterobacter spp
- motile
- gram negative
- bacillus
Serratia marcescens
- gram negative
- bacillus
- motile
- produce a distinct red pigment
Klebsiella pneumoniae is common in
alcoholics, leads to abscesses, and often causes aspiration pneumonia
Klebsiella pneumoniae bacterial cells are surrounded by
a prominent polysaccharide capsule
The sputum produced by patients with Klebsiella pneumoniae is classically described as
“currant jelly sputum”
Klebsiella pneumoniae bacteria are
- gram negative
- bacillus
- immotile
- urease positive
Serratia marcescens produces a
distinct red pigment
Cavitary lesions resembling those in tuberculosis may develop in
Klebsiella pneumoniae pulmonary infections
Salmonella
- gram negative
- bacilli
- motile
- form black colonies on Hektoen enteric agar (HE) due to production of H2S (differentiating them from Shigella spp., which form green colonies on HE)
- encapsulated
- acid labile
- can cause osteomyelitis in sickle cell patients
- facultative intracellular within macrophages
Salmonella enteritidis and typhi bacteria form
black colonies on Hektoen enteric agar (HE) due to production of H2S (differentiating them from Shigella spp., which form green colonies on HE)
Chickens are the reservoir for
Salmonella enteritidis
Salmonella typhi colonizes
the gallbladder of chronic carriers
Typhoid fever
- caused by Salmonella typhi bacteria
- can present with a characteristic rash known as “rose spots”
- the khaki-green stools seen in typhoid fever are sometimes referred to as “pea soup” stools
Treatment for salmonella
fluoroquinolones are effective against Salmonella typhi (infections caused by Salmonella enteritidis typically do not require antibiotic therapy)
Vaccination for Salmonella typhi
a vaccination is available for Salmonella typhi only (the oral vaccine contains live attenuated Salmonella typhi, and the intramuscular vaccine includes a Salmonella typhi capsular antigen)
Salmonella enteritidis (and other nontyphoidal serotypes) most commonly cause
a self-limited gastroenteritis
Salmonella enteritidis and typhi bacteria possess
a type III secretion system that delivers effector proteins directly into host cells
Shigella
- gram negative
- bacilli
- immotile
- acid-resistant (a low inoculum is required to cause infection)
Shigella spp. bacteria form
green colonies on Hektoen enteric agar (HE) (differentiating them from Salmonella spp., which form black colonies on HE)
Shigella spp. invade
M cells in Peyer’s patches of the gastrointestinal mucosa (where they induce host cell apoptosis and manipulate actin filaments of the eukaryotic cytoskeleton to achieve intracellular motility)
Shigella spp. can
manipulate the eukaryotic cytoskeleton (primarily actin filaments) to achieve intracellular motility after invading M cells in Peyer’s patches of the gastrointestinal mucos
bloody diarrhea is a common symptom of
shigellosis