Shigella

Which virulence factor of Shigella is responsible for invasion of intestinal epithelial cells and is encoded by a plasmid?

A 6-year-old child from Delhi presents with acute onset bloody diarrhea, fever, and abdominal cramps for 3 days. Stool microscopy shows numerous RBCs and WBCs. Culture on MacConkey agar shows non-lactose fermenting colonies. Which is the most appropriate next investigation to confirm the diagnosis of Shigella?

A 6-year-old child from rural India presents with acute bloody diarrhea, fever, and abdominal cramps for 3 days. Stool culture grows a gram-negative rod that is non-motile, non-lactose fermenting, and oxidase negative. Which Shigella species is the most common cause of dysentery in India?

Which site is the most common site of infection and inflammation in Shigella dysentery?

Which feature best distinguishes Shigella from Salmonella in a gram-negative bacillus isolated from a patient with acute bloody diarrhea in Delhi?