A 34-year-old man returns from South Asia presenting with profuse watery diarrhea, severe dehydration, and abdominal cramping for 3 days. Vital signs show BP 90/60 mmHg, HR 118/min, RR 20/min, and temperature 37.2°C. Stool culture grows a curved gram-negative rod that is oxidase-positive with elevated stool osmolar gap. He denies bloody stools. Which of the following best describes the mechanism of the enterotoxin produced by this organism?
- A)Inactivation of the 60S ribosomal subunit
- B)Cleavage of SNARE proteins in inhibitory neurons
- C)Cleavage of desmoglein in the superficial epidermis
- D)ADP ribosylation of Gs causing increased cyclic AMPGABARITO
- E)Activation of superantigen mediated cytokine release
Explicação
Vibrio cholerae toxin ADP ribosylates Gs, leading to persistent activation of adenylate cyclase, elevated cyclic AMP, and massive chloride and water secretion. The result is secretory diarrhea without invasion or inflammatory destruction of the bowel. Ver explicação completa e trilha adaptativa →