Differential Diagnosis for Tick-Borne Illness with Diarrhea
- Single Most Likely Diagnosis
- Anaplasmosis: This is a tick-borne illness caused by the bacterium Anaplasma phagocytophilum. Diarrhea can be a symptom, along with fever, headache, and muscle pain. It's a common tick-borne disease in many parts of the world, making it a likely candidate.
- Other Likely Diagnoses
- Babesiosis: Caused by the parasite Babesia microti, this illness can lead to gastrointestinal symptoms including diarrhea, in addition to fever, fatigue, and hemolytic anemia.
- Ehrlichiosis: Similar to anaplasmosis, ehrlichiosis is caused by bacteria in the Ehrlichia genus and can present with diarrhea, along with other symptoms like fever and headache.
- Do Not Miss Diagnoses
- Rocky Mountain Spotted Fever (RMSF): Although diarrhea is not the most common symptom, RMSF is a severe and potentially deadly disease if not treated promptly. It's caused by Rickettsia rickettsii and transmitted by ticks.
- Tick-Borne Relapsing Fever (TBRF): Caused by various Borrelia species, TBRF can present with a wide range of symptoms, including diarrhea. It's less common but can be severe, especially if not diagnosed and treated early.
- Rare Diagnoses
- Southern Tick-Associated Rash Illness (STARI): Also known as Masters disease, STARI can cause a rash and other symptoms, but gastrointestinal symptoms like diarrhea are less commonly reported. It's transmitted by the lone star tick.
- Powassan Virus Disease: A rare but potentially severe tick-borne illness that can cause encephalitis and meningitis. Gastrointestinal symptoms are not the primary presentation, but they can occur.