Peritonitis, an inflammation of the peritoneum, remains a significant complication in patients undergoing peritoneal dialysis (PD). Among the causative agents, Escherichia coli (E. coli) is notably prevalent, often leading to severe clinical outcomes. The emergence of extended-spectrum beta-lactamase (ESBL)-producing E. coli strains has further complicated treatment protocols, necessitating a thorough understanding of the associated risk factors, clinical manifestations, and effective management strategies.
Epidemiology and Risk Factors
Studies have identified E. coli as a leading cause of gram-negative peritonitis in PD patients. In a South China dialysis center, E. coli accounted for 59.2% of monomicrobial gram-negative peritonitis cases. Notably, 35.5% of these isolates were ESBL-producing strains, indicating a significant prevalence of antibiotic resistance.
Risk factors contributing to the development of ESBL-producing E. coli peritonitis include prior episodes of peritonitis, recent use of cephalosporins, and the administration of gastric acid inhibitors. Patients with a history of peritonitis exhibited a higher likelihood of harboring ESBL-producing strains.
Clinical Outcomes
The clinical course of E. coli peritonitis varies, with ESBL production playing a pivotal role in prognosis. Patients infected with ESBL-producing strains experience higher rates of treatment failure and mortality. Specifically, treatment failure rates were reported at 45.5% in the ESBL group compared to 13.0% in non-ESBL cases. Mortality due to sepsis was also higher in the ESBL group (27.3% vs. 3.9%).
Additional factors influencing poor outcomes include a Charlson Comorbidity Index (CCI) score above 3, the presence of diabetes mellitus, and hypoalbuminemia (≤30 g/l) upon admission. These conditions significantly increase the risk of treatment failure.
Antibiotic Resistance and Treatment Challenges
The rise of ESBL-producing E. coli strains poses significant challenges in the management of peritonitis. These strains exhibit resistance to multiple antibiotics, limiting therapeutic options. Empirical treatments often become ineffective, necessitating the use of broader-spectrum or combination antibiotic therapies. However, the use of cephalosporins has been associated with the development of ESBL-producing strains, suggesting the need for cautious antibiotic selection.
Management Strategies
Effective management of E. coli peritonitis involves prompt diagnosis, appropriate antibiotic therapy, and consideration of patient-specific factors. Extending the duration of antibiotic treatment from 2 to 3 weeks or more has been shown to reduce the risk of relapse and repeat infections. Additionally, addressing underlying comorbidities such as diabetes and correcting hypoalbuminemia may improve clinical outcomes.
In cases of polymicrobial peritonitis, which are often associated with bowel perforation or significant bowel disease, an aggressive search for underlying pathology is warranted. Polymicrobial infections are linked to higher rates of treatment failure and mortality, underscoring the need for comprehensive management approaches.
