# Presence of Potential Enteropathogenic Bacteria in Cats and Association With Diarrhea in Multicat Households

## TL;DR

This study found no significant link between common gut bacteria and diarrhea in cats living in multicat households.

## Contribution

The study provides evidence against routine PCR testing for specific bacteria in diagnosing feline diarrhea.

## Key findings

- None of the tested bacteria were significantly associated with diarrhea in cats.
- E. coli was detected in all fecal samples, but it was not linked to diarrhea.
- PCR testing for fecal bacteria is not recommended for routine diagnosis of feline diarrhea.

## Abstract

Diarrhea in cats is common in multicat households, and fecal panels are frequently used to diagnose potential enteropathogenic bacteria.

To evaluate the presence of potential fecal enteropathogenic bacteria and their association with diarrhea in multicat households. The null hypothesis was that potential enteropathogenic bacteria were not related to diarrhea in the cohort.

In total, 234 cats from 41 privately owned catteries were included.

In this prospective study, feces were evaluated for consistency according to a visual scoring system (Purina Fecal Score). Scores from 4 to 7 were defined as diarrhea. Quantitative PCR for Escherichia coli,
Clostridium perfringens
encoding the α toxin gene (cpa),
Clostridium perfringens
encoding the enterotoxin gene (cpe), Clostridioides difficile, Campylobacter jejuni/coli, and Salmonella enterica was used. Logistic regression was used to evaluate the impact of selected bacteria on diarrheic feces (fecal score ≥ 4). p values were corrected for multiple comparisons (q values in results). A q value < 0.05 was considered to indicate statistical significance.

23/234 cats (9.8%) had diarrhea. None of the selected bacteria were significantly associated with diarrhea (cpa: q = 0.10, cpe: q = 0.20,
C. jejuni
: q = 0.70).
E. coli
was detected in all tested fecal samples (100%). The associations of Cl. difficile (detected in 2.3% of cats),
C. coli
(0%), and
S. enterica
(0.9%) with diarrhea could not be evaluated due to the small sample sizes.

Fecal bacteria detected via PCR were not associated with clinical signs of diarrhea in multicat households. These data do not support the use of PCR for fecal bacteria for baseline routine diagnostic work‐up of diarrhea in cats.