Successful treatment of multidrug-resistant granulomatous colitis and rectal stricture in a French bulldog.

A young French bulldog was presented with persistent hemorrhagic diarrhea and suspected rectal stricture unresponsive to previous medical management. Comprehensive diagnostic tests, including blood work, colonoscopy, biopsy, antimicrobial susceptibility testing, and fluorescence in situ hybridization analysis, confirmed granulomatous colitis with invasive Escherichia coli. Culture testing identified a multidrug-resistant strain susceptible to meropenem. Concurrently, a rectal stricture was confirmed and managed with 3 repeat endoscopic balloon dilations. Systemic improvement was noted mid-treatment, and the stricture resolved at subsequent follow-up. Key clinical message: This case report highlights the successful diagnosis and management of multidrug-resistant granulomatous colitis in a French bulldog, including the use of meropenem for targeted antimicrobial therapy and repeat endoscopic balloon dilations for rectal stricture resolution. It underscores the importance of accurate diagnosis, appropriate antimicrobial selection, and structural intervention in the management of complex cases.