Salmonella (GNB strict pathogen) Flashcards
(30 cards)
what biological feature is always present on salmonella?
- Oxidase (-)*
- Non-lactose Fermenting (white on MacConkey)**
what is salmonella enterica’s biology?
- Gram (-) bacilli
- Facultative anaerobe
- Capsule
- Motile, peritrichous flagella*
- Oxidase (-)**
- Non-lactose fermenting***
- H2S production****
what salmonella serotype will cause typhoid fever?
Salmonella enterica serovar Typhi or Paratyphi
what salmonella serotype will cause Gastroenteritis?
Non-typhoidal Salmonella
what is the pathogenesis of salmonella?
Invades ileum IEC in addition to M cells via T3SS.
how does salmonella avoid phagolysis?
Avoids phagolysis due to capsule.
Can salmonella live intracellularly?
yes, in macrophages
what is the biology of salmonella typhi?
- Gram Negative Bacilli
- Motile,
- Non-fermenter,
- H2S production
how does salmonella typhi spread?
fecal-oral (human restricted)
what is the Pathogenesis of salmonella typhi?
invades without inflammation and lives inside macrophages
Salmonella Typhi can live permanently in what organ of the body?
gallbladder
what is the clinical presentation of typhoid fever?
- High fever lasting >7days
- Hepato-splenomegaly
- Rash “Rose Spots”
- Headache
what patient history is important in order to diagnose typhoid fever?
travel especially to southeast asia
what complications can occur with typhoid fever?
1) septic death
2) asymptomatic chronic carrier
what is the biology of non-typhoidal salmonella?
- Gram Negative Bacilli
- Motile,
- Non-fermenter,
- H2S production
- Oxidase (-)*
what are the most common Non-typhoidal Salmonella?
S. Enteritidis and Typhimurium
how does non-typhoidal salmonella spread?
Zoonotic Reservoir
(found in animals)
poultry, pigs, reptiles
what is the Pathogenesis of non-typhoidal salmonella?
Invade ileum and M cells
Crosses to lamina propria and triggers inflammation.
what immunity will activate to combat the non-typhoid salmonella?
cell mediated immunity
when does Non-typhoidal Salmonella become systemic?
cell mediated immunity compromised
what disease can non-typhoidal salmonella occur on a healthy host?
Mild Gastroenteritis = loose, watery stools
how common is non-typhoidal salmonella in USA?
very common
what will salmonellosis (non-typhoidal salmonella) cause in old age and children individuals?
- Severe Gastroenteritis = high fever, watery/bloody stools
- GI + Bacteremia = high fever, septic symptoms
what will salmonellosis (non-typhoidal salmonella) cause in the immunocompromised?
- Typhoid Fever = high fever, septic symptoms
- Meningitis = high fever, severe headache, etc.
