# Relapsing peritoneal dialysis‑associated peritonitis caused by Pseudomonas oryzihabitans with concurrent tunnel infection: a case report and literature review

## TL;DR

A patient with peritoneal dialysis developed peritonitis caused by Pseudomonas oryzihabitans, which recurred with a tunnel infection and was successfully treated without removing the dialysis catheter.

## Contribution

This is the first reported case of relapsing Pseudomonas oryzihabitans peritonitis with concurrent tunnel infection successfully treated without catheter removal.

## Key findings

- Pseudomonas oryzihabitans peritonitis recurred after initial treatment and was complicated by tunnel infection.
- Cuff-shaving surgery combined with antibiotics resolved the infection without catheter removal.
- The infection originated from an exit-site infection caused by a different organism before relapse.

## Abstract

Peritoneal dialysis (PD)-associated peritonitis is linked to an increased risk of catheter removal and PD discontinuation, with these risks occurring more frequently in relapsing peritonitis than in primary peritonitis. Relapses are often attributed to persistent infection originating from the PD catheter, including tunnel infection (TI). Although Pseudomonas oryzihabitans is a commensal bacterium and recognized opportunistic pathogen, only a limited number of cases of P. oryzihabitans peritonitis—and none involving relapsing peritonitis with concurrent TI—have been reported. A 73-year-old Japanese man undergoing PD presented with abdominal pain, fatigue, fever, and decreased PD fluid drainage. He was diagnosed with PD-associated peritonitis caused by P. oryzihabitans, which was preceded by a persistent exit-site infection due to different organisms. A 21-day course of antimicrobial therapy combined with peritoneal lavage led to clinical improvement. However, 27 days after completing treatment, he developed relapsing peritonitis due to P. oryzihabitans, complicated by TI suspected on computed tomography. However, the patient declined catheter removal and chose outpatient intraperitoneal antibiotics. The relapse resolved, but persistent yellow drainage prompted cuff-shaving surgery. We present a case of peritonitis caused by P. oryzihabitans, initially presenting with exit site infection and later complicated by TI at recurrence, that was successfully treated without PD catheter removal. This case suggests that cuff-shaving combined with appropriate antimicrobial therapy may be an effective treatment option for P. oryzihabitans peritonitis when the peritonitis and catheter infection are not caused by the same organism.