# Salmonella enterica ser Saintpaul Colitis Mimicking Crohn's Disease

## TL;DR

A case of Salmonella Saintpaul colitis was mistaken for Crohn's disease, highlighting the need to rule out infections before starting immunosuppressive therapy.

## Contribution

This case report presents a rare instance of Salmonella Saintpaul causing colitis that mimicked Crohn's disease.

## Key findings

- Salmonella Saintpaul colitis can mimic Crohn's disease clinically and endoscopically.
- Long-term follow-up confirmed the infection as the cause, avoiding unnecessary immunosuppressive therapy.
- The case underscores the importance of considering infectious causes before initiating IBD treatment.

## Abstract

Diagnosing inflammatory bowel disease (IBD) can be challenging in the presence of mimicking conditions, such as infectious colitis. An accurate diagnosis is important to avoid unnecessary treatment. Nontyphoidal Salmonella species are an important cause of infectious colitis that at times can mimic IBD. Salmonella enterica serotype Saintpaul has caused numerous fatal foodborne gastroenteritis outbreaks worldwide. It has also been known to cause other infections, such as bacteremia, splenic abscesses, and meningitis, but has only rarely been known to cause colitis. Worryingly, antibiotic resistance rates of S. Saintpaul are rising. This case report presents a woman with S. Saintpaul colitis mimicking Crohn's disease. Despite an initial plan to start biologic therapy, long-term follow-up while off immunosuppressant therapy confirmed S. Saintpaul as the underlying cause of colitis, sparing our patient long-term immunosuppression. This case highlights the importance of ruling out infectious colitis before beginning long-term immunosuppressive therapy and the challenges of mimicking conditions as well as the novelty of the Saintpaul serotype causing colitis.