Review Question - QID 217187

This patient has Bacillus cereus foodborne illness leading to acute-onset watery diarrhea, vomiting, nausea, and abdominal pain within hours of consuming reheated rice. The classic presentation of this illness that is triggered by heat-stable enterotoxins.

The acute onset of vomiting and diarrhea in a patient within hours after consuming a meal is suggestive of a preformed toxin. Preformed toxins occur in pathogens such as Staphylococcus aureus and Bacillus cereus. The most important clue is in the clinical history, which helps differentiate between the two. Staphylococcus aureus is spread via raw or prepared food such as dairy, meat, eggs, or potato salads may affect multiple individuals in settings such as a group picnic. On the other hand, Bacillus cereus affects patients after reheated rice. This is because the bacteria is heat-stable. Spores from this bacteria survive the cooking process and germinate when rice is kept warm, which results in enterotoxin formation. Diagnosis is clinical indicated by rapid onset vomiting and diarrhea. Management is fluid repletion and is self-limited within 24-48 hours.

Switaj et al. discuss the etiologies and clinical presentations of various organisms implicated in food poisoning.

Incorrect Answers:
Answer 2: Clostridium difficile infection is associated with recent antibiotic use and results in profuse, watery, foul-smelling diarrhea that is caused by Toxin A (an enterotoxin) and Toxin B (a cytotoxin).

Answer 3: Norovirus infection can result in acute onset diarrhea and vomiting. The virus is transmitted via the fecal-oral route and is very virulent, classically affecting large groups of people such as on a cruise ship which helps distinguish this etiology from other causes of profuse, watery diarrhea.

Answer 4: Shigella dysenteria can cause invasive gastrointestinal disease as a result of producing shiga exotoxin, which leads to marked diarrhea that is bloody, a distinguishing factor. It is often transmitted through the consumption of undercooked beef.

Answer 5: Staphylococcus aureus poisoning can result in nausea, vomiting, diarrhea, and abdominal pain within 1-8 hours of incubation. It is caused by consumption of preformed toxin in contaminated foods. Vomiting symptoms are much more common in S. aureus food poisoning compared to diarrhea, which may help narrow down this etiology from others that are implicated in more pronounced diarrheal illness.

Bullet summary:
Heat stable toxins are responsible for the acute onset of watery diarrhea, and occasionally vomiting, in patient's affected by Bacillus cereus, which is classically found in reheated rice.