Potential clinical value of catheters impregnated with antimicrobials for the prevention of infections associated with peritoneal dialysis.

INTRODUCTION: Peritoneal dialysis (PD) is a widely used dialysis modality, which offers the advantage of being a home therapy but is associated with a risk of potentially serious infections, including exit site infection, catheter tunnel infection, and peritonitis that may result in morbidity, technique failure, and increased mortality. Catheters impregnated with antimicrobials hold promise as a novel technique to reduce PD associated infections. AREAS COVERED: We describe PD modalities, catheters, technique, complications, and the microbiology of associated infections, as well as standard measures to reduce the risk of infection. A novel technique for the impregnation of silicone devices with antimicrobial agents has been used to produce antimicrobial impregnated ventricular shunt catheters with proven clinical efficacy that have now been adopted as the standard of care to reduce neurosurgical infections. Using the same technology, we have developed PD and urinary catheters impregnated with sparfloxacin, triclosan, and rifampicin. Safety and tolerability have been demonstrated in urinary catheters, and a similar study is planned in PD catheters. EXPERT OPINION: Catheters impregnated with antimicrobials offer a simple technique to reduce PD associated infections and thereby enable more people to enjoy the advantages of PD. Clinical trials are needed to establish efficacy.

Peritoneal dialysis (PD) is a type of treatment for kidney failure. To perform PD, a silicone tube is placed in the abdomen and the other end exits through the skin. Fluid is run into the abdomen via the tube and then drained out again after 1­12 hours. This process is repeated multiple times per day. Toxins and other waste chemicals normally removed by the kidneys enter the fluid, while it is in the abdomen and are then removed from the body when the fluid is drained out. In this way, PD partially replaces kidney function. Sometimes bacteria get into the tube, and this can cause serious infections in the abdomen. At present, measures available to prevent PD tube infections include careful hygiene when handling the tube, application of antibiotic creams or ointments to the exit site or treatment with antibiotics at the time of medical procedures that may increase infection risk. Despite these measures, peritonitis (abdominal infection) is one of the most common causes of people having to stop PD and change to another form of dialysis that involves direct filtration of the blood (hemodialysis). Frequent use of antibiotics may also cause the bacteria that cause peritonitis to become resistant to antibiotics. There is, therefore, an urgent need to develop new ways to prevent PD tube infections. Tubes have been used in patients who have a particular type of brain surgery with antibiotics introduced into the material that the tube is made from, and in these patients, the risk of infection has been reduced by 60­80%. The same technology is also being tested for urine tubes that are placed in the bladder and tubes used for PD. These urine tubes and PD tubes need further testing to establish safety and effectiveness. Though our experience with them leads us to expect that they are safe, the authorities that control new drugs and devices require us to show this beyond doubt before they can be introduced into routine care.

Peritoneal Ultrafiltration for Heart Failure: Lessons from a Randomized Controlled Trial.

Peritoneal ultrafiltration (PuF) has been employed for severe heart failure (HF), but evidence for its benefit is lacking. The Peritoneal Dialysis for Heart Failure (PDHF) study was a multicenter prospective randomized controlled trial which aimed to investigate this issue. The trial stopped early due to inadequate recruitment. We describe methods, trial activity, and lessons learned.The trial aimed to recruit 130 participants with severe diuretic-resistant HF (New York Heart Association [NYHA] 3/4) and chronic kidney disease (CKD) stage 3/4 on optimal medical treatment for ≥ 4 weeks from 6 UK centers. Participants were randomized to either continuation of conventional HF treatment or to additionally receiving PuF (1 overnight exchange using Icodextrin dialysate). Primary outcome was change in 6-minute walk test (6MWT) between baseline and 28 weeks (end of trial). Secondary outcomes were changes in patient reported quality of life as assessed by the Kansas City Cardiomyopathy Questionnaire, short form 36 (SF 36) health survey results, hospitalization, and mortality.Over a 2-year period, 290 patients were screened from which only 20 met inclusion criteria and 10 were recruited. Reasons for ineligibility were fluctuating estimated glomerular filtration rate (eGFR), suboptimal HF treatment, frailty, and patients being too unwell for randomization. Barriers to recruitment included patient frailty, with some participants considered only when they were at end of life, unwillingness to engage in an invasive therapy, and suboptimal coordination between cardiology and renal services. This is a challenging patient group in which to perform research, and lessons learned from the peritoneal dialysis (PD)-HF trial will be helpful in the planning of future studies in this area.