Utility of ultrasonographic examination in catheter-related infections in peritoneal dialysis: a clinical approach.

Peritoneal dialysis- (PD) related infections continue to be a major cause of morbidity and mortality in patients on renal replacement therapy via PD. However, despite the great efforts in the prevention of PD-related infectious episodes, approximately one third of technical failures are still caused by peritonitis. Recent studies support the theory that ascribes to exit-site and tunnel infections a direct role in causing peritonitis. Hence, prompt exit site infection/tunnel infection diagnosis would allow the timely start of the most appropriate treatment, thereby decreasing the potential complications and enhancing technique survival. Ultrasound examination is a simple, rapid, non-invasive and widely available procedure for tunnel evaluation in PD catheter-related infections. In case of an exit site infection, ultrasound examination has greater sensitivity in diagnosing simultaneous tunnel infection compared to the physical exam alone. This allows distinguishing the exit site infection, which will likely respond to antibiotic therapy, from infections that are likely to be refractory to medical therapy. In case of a tunnel infection, the ultrasound allows localizing the catheter portion involved in the infectious process, thus providing significant prognostic information. In addition, ultrasound performed after two weeks of antibiotic administration allows monitoring patient response to therapy. However, there is no evidence of the usefulness of ultrasound examination as a screening tool for the early diagnosis of tunnel infections in asymptomatic PD patients.