A 25-year-old woman comes to the emergency department due to 2 days of abdominal pain and bloody diarrhea. A few days ago, she attended a church barbeque party. The patient lives alone and has no medical problems. She does not know if anyone else at the party developed similar symptoms. Her temperature is 37.1 C (98.8 F), blood pressure is 119/76 mm Hg, pulse is 92/min, and respirations are 16/min. There is abdominal tenderness with no rebound or guarding. Guaiac-positive bloody stools are detected on rectal examination. Stool cultures reveal an Escherichia coli strain that does not produce glucuronidase and does not ferment sorbitol on sorbitol-containing MacConkey agar. Which of the following best describes the mechanism of action of the toxin produced by these bacteria?

Question

A 25-year-old woman comes to the emergency department due to 2 days of abdominal pain and bloody diarrhea.  A few days ago, she attended a church barbeque party.  The patient lives alone and has no medical problems.  She does not know if anyone else at the party developed similar symptoms.  Her temperature is 37.1 C (98.8 F), blood pressure is 119/76 mm Hg, pulse is 92/min, and respirations are 16/min.  There is abdominal tenderness with no rebound or guarding.  Guaiac-positive bloody stools are detected on rectal examination.  Stool cultures reveal an Escherichia coli strain that does not produce glucuronidase and does not ferment sorbitol on sorbitol-containing MacConkey agar.  Which of the following best describes the mechanism of action of the toxin produced by these bacteria?

Quizplus · Accepted Answer

Eductional Objective: Enterohemorrhagic Escherichia coli O157:H7 infection is a common cause of bloody diarrhea and can lead to hemolytic-uremic syndrome.  It is associated with consumption of undercooked ground beef and elaborates a Shiga-like toxin capable of inhibiting protein synthesis in colonic mucosal cells and renal endothelial cells.  This particular strain of E coli is unable to ferment sorbitol and does not produce a glucuronidase.

A 25-Year-Old Woman Comes to the Emergency Department Due to 2