Shigella Flashcards
Shigella almost exculsively effects what species and where?
primates large bowel
What is the most common species of Shigella?
Shigella dysenteriae
What is the most important virulence factor of Shigella dysenteriae?
Shiga toxin
How does Shigella look under a microscope?
gram negative rod
What cells does the shigella adhere to in the large bowel?
M cells and epithelial cells
Shiga toxin disrupts ____ synthesis in the endothelial cells and causes cell death
protein
What are the effector proteins that are injected via type III secretions from Shigella that induce lysis of phagocytes?
IpaB and IpaC
What effector proteins of Shigella help with mobility of shigella inside the cell
IcsA and IcsB
*highjack the cytoskeleton
how is shigella transmitted?
Fecal oral transmission
*highly infectious
The presence of ____ will overcome Shigella
normal flora
How does shigella survive in the PH of the stomach?
RpoS (RNS polymerase)
Shigella reaches the intestinal cells and destroy the mucus via the _____ attach to the M cells via the _____
destroys the mucus via the Pic
Attaches to the M cells mainly via the IpaD
What does Shigella Dysenteria cause in primates?
hemorrhagic diarrhea and hemolytic uremic syndrome
True/False: Antibody secretion is important for Shigella
true
*They bind and protect the bacteria from adhering to the large bowel
Case of african green monkey that is 15 years old in a very packed cage. Highly stressed out and starts presenting bloody diarrhea. What would the best differential be?
Shigella
side note (Now you isolate a lactose positive organism and during a necropsy you find attaching and effasing lesions in the GI tract. What is the most likely agent now? Enterohemorragic E. coli)
Side note: (now you isolate a gram positive rod which is positive for the naglers test. What is the best differential? Clostridium perfringens)
