Differential Diagnosis for Diarrhea Post Raw Fish

• Single most likely diagnosis
  • Giardiasis: This is a common cause of diarrhea after consuming contaminated water or food, including raw fish. Giardia lamblia is a parasite that can be found in raw or undercooked fish, especially in areas with poor water quality.
• Other Likely diagnoses
  • Anisakiasis: This is an infection caused by the Anisakis parasite, which is commonly found in raw or undercooked fish. Symptoms can include diarrhea, abdominal pain, and nausea.
  • Vibrio infection: Vibrio vulnificus and Vibrio parahaemolyticus are bacteria that can be found in raw or undercooked fish, particularly in seafood from warm waters. They can cause diarrhea, vomiting, and abdominal pain.
  • Salmonella or Shigella infection: While less common, these bacteria can also be present in raw fish and cause gastrointestinal symptoms.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Ciguatera fish poisoning: This is a potentially life-threatening condition caused by eating fish contaminated with ciguatoxins. Symptoms can include diarrhea, vomiting, and abdominal pain, as well as neurological symptoms like numbness and tingling.
  • Scombroid fish poisoning: This condition is caused by eating fish with high levels of histamine, which can cause symptoms like diarrhea, vomiting, and abdominal pain, as well as flushing, itching, and difficulty breathing.
• Rare diagnoses
  • Diphyllobothriasis: This is a parasitic infection caused by the Diphyllobothrium latum tapeworm, which can be found in raw or undercooked fish. Symptoms can include diarrhea, abdominal pain, and weight loss.
  • Echinococcosis: This is a rare parasitic infection caused by the Echinococcus tapeworm, which can be found in raw or undercooked fish. Symptoms can include diarrhea, abdominal pain, and liver or lung problems.