What is the clinical significance of a positive E. coli (Escherichia coli) O157 gene test in a young patient with ulcerative colitis (UC) who recently returned from India and developed watery diarrhea?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: March 7, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for a Young Patient with UC, E coli 0157 Gene Positive, and Watery Diarrhea after Returning from India

  • Single Most Likely Diagnosis
    • Infectious Colitis (E coli 0157 infection): Although E coli 0157 was not isolated, the presence of the gene suggests a possible infection, which could be exacerbated by the patient's underlying ulcerative colitis (UC). Travel to India increases the risk of various infections, but the specific mention of E coli 0157 gene positivity points towards this as a primary consideration.
  • Other Likely Diagnoses
    • Traveler's Diarrhea (due to other pathogens): Given the patient's recent travel to India, other common causes of traveler's diarrhea such as Salmonella, Shigella, Campylobacter, or viral pathogens should be considered, especially since the symptoms started after returning from travel.
    • UC Exacerbation: The patient's underlying UC could be experiencing a flare, potentially triggered by the travel, changes in diet, or an infection. The presence of watery diarrhea could be a manifestation of this flare.
  • Do Not Miss Diagnoses
    • Cholera: Although less common, given the travel history to India, cholera should be considered, especially if the diarrhea is profuse and watery. Cholera can be life-threatening if not promptly treated.
    • Amoebic Dysentery: Caused by Entamoeba histolytica, this condition can present with bloody diarrhea but also with watery stools in some cases. It's a significant consideration in travelers to endemic areas.
    • Giardiasis: Giardia lamblia infection can cause watery diarrhea and is a common cause of waterborne outbreaks. It's particularly relevant in travelers who may have consumed contaminated water.
  • Rare Diagnoses
    • Cyclosporiasis: This is an intestinal infection caused by Cyclospora cayetanensis, which can cause prolonged and watery diarrhea. It's more common in travelers to certain regions, including parts of Asia.
    • Microsporidiosis: Caused by microsporidia, this infection can lead to chronic diarrhea, especially in immunocompromised individuals. However, it's less common and typically considered when other diagnoses have been ruled out.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.