Twelve people who ate chicken curry kept overnight at room temperature develop abdominal cramps and watery diarrhoea 12 hours later. Vomiting and fever are absent and all recover in 24 hours. Spore-forming Gram-positive rods are cultured from the leftover food. The responsible enterotoxin is best described as:
- A Heat-labile superantigen acting through V-beta specific T-cell activation
- B Heat-labile protein that alters epithelial permeability, produced during sporulation in the gut ✓
- C Heat-stable toxin that activates adenylate cyclase in enterocytes
- D Phospholipase C that hydrolyses lecithin in enterocyte membranes
Correct answer: B. Heat-labile protein that alters epithelial permeability, produced during sporulation in the gut
Explanation
This is Clostridium perfringens food poisoning, classically linked to reheated meat and poultry dishes. Its type A strains elaborate a heat-labile enterotoxin that acts on the small intestinal epithelium to disturb ion and fluid balance, producing cramps and diarrhoea without vomiting after an 8 to 16 hour incubation. Phospholipase B is the alpha toxin of gas gangrene and myonecrosis, and the adenylate cyclase mechanism belongs to cholera and related enterotoxins.
Reference: Jawetz, Melnick and Adelberg's Medical Microbiology, 28th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.