# Not Your Usual Culprit: Relapsing Salmonella enterica Serovar Infantis Urinary Tract Infection

## TL;DR

A rare case of recurring urinary tract infection caused by Salmonella Infantis in a 60-year-old woman with multiple health conditions is reported.

## Contribution

This case highlights the unusual recurrence of S. Infantis UTI and the role of genomic sequencing and hygiene measures in its resolution.

## Key findings

- S. Infantis UTI recurred three times in a year in a high-risk patient.
- Genomic sequencing confirmed relapse from intestinal colonization.
- A seven-day antibiotic regimen and improved hygiene led to sustained resolution.

## Abstract

Urinary tract infection due to Salmonella enterica serovar Infantis (S. Infantis) is exceptionally rare and typically linked to host vulnerabilities. We report a case of a woman in her 60s with metastatic renal cancer, diabetes, chronic kidney disease, and prior splenectomy who developed three episodes of UTI within a year. Repeated urine cultures grew S. Infantis, and whole-genome sequencing confirmed relapse from intestinal colonization. After sequential short antibiotic courses, sustained resolution followed a seven-day regimen combined with reinforced pet-related hygiene measures. This case highlights the importance of considering unusual uropathogens, using genomic tools to confirm persistence, and addressing potential zoonotic reservoirs.