Prevention of peritoneal dialysis-related infections

Variation in Peritoneal Dialysis-Related Peritonitis Outcomes in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS)

RATIONALE & OBJECTIVE

Peritoneal dialysis (PD)-associated peritonitis is a significant PD-related complication. We describe the likelihood of cure after a peritonitis episode, exploring its association with various patient, peritonitis, and treatment characteristics.

STUDY DESIGN

Observational prospective cohort study.

SETTING & PARTICIPANTS

1,631 peritonitis episodes (1,190 patients, 126 facilities) in Australia, New Zealand, Canada, Japan, Thailand, the United Kingdom, and the United States.

EXPOSURE

Patient characteristics (demographics, patient history, laboratory values), peritonitis characteristics (organism category, concomitant exit-site infection), dialysis center characteristics (use of icodextrin and low glucose degradation product solutions, policies regarding antibiotic self-administration), and peritonitis treatment characteristics (antibiotic used).

OUTCOME

Cure, defined as absence of death, transfer to hemodialysis (HD), PD catheter removal, relapse, or recurrent peritonitis within 50 days of a peritonitis episode.

ANALYTICAL APPROACH

Mixed-effects logistic models.

RESULTS

Overall, 65% of episodes resulted in a cure. Adjusted odds ratios (AOR) for cure were similar across countries (range, 54%-68%), by age, sex, dialysis vintage, and diabetes status. Compared with Gram-positive peritonitis, the odds of cure were lower for Gram-negative (AOR, 0.41 [95% CI, 0.30-0.57]), polymicrobial (AOR, 0.30 [95% CI, 0.20-0.47]), and fungal (AOR, 0.01 [95% CI, 0.00-0.07]) peritonitis. Odds of cure were higher with automated PD versus continuous ambulatory PD (AOR, 1.36 [95% CI, 1.02-1.82]), facility icodextrin use (AOR per 10% greater icodextrin use, 1.06 [95% CI, 1.01-1.12]), empirical aminoglycoside use (AOR, 3.95 [95% CI, 1.23-12.68]), and ciprofloxacin use versus ceftazidime use for Gram-negative peritonitis (AOR, 5.73 [95% CI, 1.07-30.61]). Prior peritonitis episodes (AOR, 0.85 [95% CI, 0.74-0.99]) and concomitant exit-site infection (AOR, 0.41 [95% CI, 0.26-0.64]) were associated with a lower odds of cure.

LIMITATIONS

Sample selection may be biased and generalizability may be limited. Residual confounding and confounding by indication limit inferences. Use of facility-level treatment variables may not capture patient-level treatments.

CONCLUSIONS

Outcomes after peritonitis vary by patient characteristics, peritonitis characteristics, and modifiable peritonitis treatment practices. Differences in the odds of cure across infecting organisms and antibiotic regimens suggest that organism-specific treatment considerations warrant further investigation.

Prevalence and risk factors of exit-site infection in incident peritoneal dialysis patients

BACKGROUND

Exit-site infection (ESI) is a common complication in peritoneal dialysis (PD) patients. Clearly understanding the risk factors may be useful for the prevention of ESI. This study was to explore the prevalence and risk factors of ESI in incident PD patients.

METHODS

We evaluated ESI in incident PD patients who had catheter insertion in our center between 1 January 2009 and 31 December 2013, with follow-up for 1 year. We collected data on demographics, clinical features, and nursing care methods of the exit site (ES).

RESULTS

We recruited 1133 incident PD patients (687 male (60.6%); mean age 47.0 ± 15.1 years), and 245 (21.6%) had diabetes. Median follow-up was 12.0 months. One hundred and thirty-one patients had 139 episodes of ESI with a rate of 92.8 patient-months per episode (0.13 episodes per year). Coagulase-negative staphylococcus was the main pathogen, accounting for 33.8% of the ESIs. Gram-positive rods, Staphylococcus aureus, Pseudomonas, fungi, and other organisms accounted for 23.0%, 15.8%, 1.4%, 1.4%, and 2.9%, respectively. No bacterial growth was found in 15.1%. There were no differences in demographic and laboratory data (age, gender, primary kidney disease, hemoglobin, white blood cell, serum albumin, blood urea nitrogen, serum creatinine, and C-reactive protein) between the ESI and non-ESI groups. Poor competency of ES care, poor catheter immobilization, history of catheter-pulling injury, and mechanical stress on the ES were significantly associated with increased risk of ESI.

CONCLUSIONS

The prevalence of ESI was 0.13 episodes per year. Poor competency of ES care, catheter mobilization, history of catheter-pulling injury, and mechanical stress by waist belt or the protective bag of PD on ES were risk factors for ESI.

Strategies to Prevent Peritonitis after Procedures: Our Opinions

Peritoneal Dialysis (PD) patients are at increased risk of peritonitis following elective colonoscopy and other potentially invasive dental or gynecological procedures. The increased risk of iatrogenic peritonitis is attributed to procedure-related factors such as instrumentation, biopsies, tissue injury, and peri-procedural bacterial contamination. Also contributory are patient-related factors such as the effect of the immunocompromised status of end-stage renal disease and the presence of intraperitoneal dialysate on the disruption of natural host defense mechanisms. We propose the use of standard peri-procedure protocols, including procedure-specific prophylactic antibiotics, and discuss the enhanced defense rationale for a dry abdomen during and sometimes after procedures. Depending on the procedure and its inherent risk of causing peritonitis, as well as the patient's ability to withhold PD for up to 3 days, we sometimes increase the intensity of PD before the procedure. We conclude that it is imperative that proceduralists and nephrologists be aware of and proactive about how to mitigate postprocedure PD complications.

Surface modification strategies for combating catheter-related complications: recent advances and challenges

This review summarizes the progress made in addressing bacterial colonization and other surface-related complications arising from catheter use.

Laparoscopic peritoneal dialysis catheter insertion using nitrous oxide under procedural sedation

BACKGROUND

Laparoscopic peritoneal dialysis catheter (LPDC) implantation using nitrous oxide (N2O) pneumoperitoneum under procedural sedation is a technique that has many advantages over conventional insertion methods. The purpose of this study was to review the LPDC insertion results at our center.

METHODS

Data from 87 consecutive patients who underwent LPDC insertion was retrospectively reviewed. All procedures were attempted under procedural sedation. After patients received intravenous and local anesthesia, a N2O pneumoperitoneum was established. Peritoneal dialysis (PD) catheters were advanced using rectus sheath tunneling. The position of the catheter was confirmed by laparoscope, and adjunct procedures such as omentopexy and adhesiolysis were performed on select patients to prevent catheter flow problems.

RESULTS

Nitrous oxide was well tolerated by 94 % of the patients. Only five patients required conversion to general anesthesia. After a mean follow-up of 18.2 months, mechanical complications included pericatheter/incision leakage (12.62 %), flow obstruction (4.60 %), incision/exit site hernia (3.45 %), hemoperitoneum (2.30 %), pleuroperitoneal fistula (1.15 %), scrotal leak (1.15 %), and migration (1.15 %). Infectious complications included exit site infection (1 episode per 312.95 patient-months) and peritonitis (1 episode per 31.93 patient-months). Revision-free catheter survival was 97.6 % after 1 year.

CONCLUSION

Laparoscopic implantation of a PD catheter with N2O pneumoperitoneum and local anesthesia is safe and effective in patients with severe renal failure. N2O is an inert gas and better tolerated as an insufflation agent, enabling awake procedures. Our results show that catheter-related functional outcomes are comparable to those in the existing literature. This approach can be recommended as a good option for catheter implantation in patients needing dialysis.

Bionic approach for the prevention of exit-site infections of percutaneous devices

Exit-site infections remain one of the main complications for percutaneous devices, such as catheters for peritoneal dialysis or drivelines for ventricular assist devices. Many efforts have been made to create a biological seal, yet without long-term success. This study investigates a new kind of percutaneous device which is coated with an extricable polymeric membrane. The bionic approach applies the naturally outwards directed growth of skin structures to technology: by pulling the protective membrane it slowly grows out of the body and a developing sulcus is exposed to dry air and an infection is avoided. In a feasibility study this kind of device was shown to reduce the rate of infection. To further investigate these devices, they were implanted in the skin of goats and observed for a period of more than 500 days. The membranes were pulled with a force of up to 2 N and the resulting movement was recorded. When being pulled, the membranes moved 0.4-0.9 mm per week, showing that the application of a continuously acting, defined force on the protective membrane causes the desired slow movement.

Antibacterial responses by peritoneal macrophages are enhanced following vitamin D supplementation

Patients with chronic kidney disease (CKD), who usually display low serum 25-hydroxyvitamin D (25D) and 1,25-dihydroxyvitamin D (1,25D), are at high risk of infection, notably those undergoing peritoneal dialysis (PD). We hypothesized that peritoneal macrophages from PD patients are an important target for vitamin D-induced antibacterial activity. Dialysate effluent fluid was obtained from 27 non-infected PD patients. Flow cytometry indicated that PD cells were mainly monocytic (37.9±17.7% cells CD14+/CD45+). Ex vivo analyses showed that PD cells treated with 25D (100 nM, 6 hrs) or 1,25D (5 nM, 6 hrs) induced mRNA for antibacterial cathelicidin (CAMP) but conversely suppressed mRNA for hepcidin (HAMP). PD cells from patients with peritonitis (n = 3) showed higher baseline expression of CAMP (18-fold±9, p<0.05) and HAMP (64-fold±7) relative to cells from non-infected patients. In 12 non-infected PD patients, oral supplementation with a single dose of vitamin D2 (100,000 IU) increased serum levels of 25D from 18±8 to 41±15 ng/ml (p = 0.002). This had no significant effect on PD cell CD14/CD45 expression, but mRNA for HAMP was suppressed significantly (0.5-fold, p = 0.04). Adjustment for PD cell CD14/CD45 expression using a mixed linear statistical model also revealed increased expression of CAMP (mRNA in PD cells and protein in effluent) in vitamin D-supplemented patients. These data show for the first time that vitamin D supplementation in vitro and in vivo promotes innate immune responses that may enhance macrophage antibacterial responses in patients undergoing PD. This highlights a potentially important function for vitamin D in preventing infection-related complications in CKD.

Identification of Targets for Prevention of Peritoneal Catheter Tunnel and Exit-Site Infections in Low Incidence Settings

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BACKGROUND

Peritoneal catheter tunnel and exit-site infection (TESI) complicates the clinical course of peritoneal dialysis (PD) patients. Adherence to recommendations for catheter insertion, exit-site care, and management of Staphylococcus aureus (SAu) carriage reduces, but does not abrogate the risk of these infections. ♦

OBJECTIVE

To reappraise the risk profile for TESI in an experienced center with a long-term focus on management of SAu carriage and a low incidence of these infections. ♦

METHOD

Following a retrospective, observational design, we investigated 665 patients incident on PD. The main study variable was survival to the first episode of TESI. We considered selected demographic, clinical, and technical variables, applying multivariate strategies of analysis. ♦

MAIN RESULTS

The overall incidence of TESI was 1 episode/68.5 patient-months. Staphylococcus aureus carriage disclosed at inception of PD (but not if observed sporadically during follow-up) (hazard ratio [HR] 1.53, p = 0.009), PD started shortly after catheter insertion (HR 0.98 per day, p = 0.011), PD after kidney transplant failure (HR 2.18, p = 0.017), lower hemoglobin levels (HR 0.88 per g/dL, p = 0.013) and fast peritoneal transport rates (HR 2.92, p = 0.03) portended an increased risk of TESI. Delaying PD ≥ 30 days after catheter insertion markedly improved the probability of TESI. Carriage of methicillin-resistant SAu since the start of PD was associated with a high incidence of TESI by these bacteria. On the contrary, resistance to mupirocin did not predict such a risk, probably due to the use of an alternative regime in affected patients. ♦

CONCLUSIONS

Adherence to current recommendations results in a low incidence of TESI in PD patients. Interventions on specific risk subsets have a potential to bring incidence close to negligible levels. Despite systematic screening and management, SAu carriage is still a predictor of TESI. Antibiotic susceptibility patterns may help to refine stratification of the risk of TESI by these bacteria. Early insertion of the peritoneal catheter should be considered whenever possible, to reduce the risk of later TESI.

A qualitative systematic review of the literature supporting a causal relationship between exit-site infection and subsequent peritonitis in patients with end-stage renal disease treated with peritoneal dialysis

OBJECTIVE

The objective of our research was to summarize and review evidence supporting a causal relationship between exit-site infection and peritonitis in peritoneal dialysis (PD) patients.

DATA SOURCES

We undertook a qualitative review of studies retrieved from MEDLINE, EMBASE, and PubMed, and supplemented that process with a hand search of references and abstracts in the literature.

STUDY SELECTION

Our quality criteria were based on the Paediatric Risk of Mortality guidelines, definitions, and recommendations from the International Society for Peritoneal Dialysis (ISPD), and the Bradford Hill criteria for causality. All identified abstracts were reviewed for content. Of 776 abstracts, 59 were selected for full-text evaluation, and 22 of those met the ISPD criteria for good-quality research in PD-related infections. Of the 22 eligible studies, 9 met the study's quality criteria and were included in the summative analysis. No articles reported sufficient data for a quantitative analysis.

DATA EXTRACTION

Information on study design, study population characteristics, definitions, peritonitis rates, exit-site care protocol, exit-site treatment protocol, follow-up period, potential bias, and outcomes was extracted. Criteria for including data in the final study were determined using ISPD guidelines.

DATA SYNTHESIS

Of the 9 included studies, 8 suggested that a history of exit-site infection increased the risk for subsequent peritonitis. Of those studies, 3 met 5 causality criteria, 4 met 4 causality criteria, and 1 met 3 causality criteria.

CONCLUSIONS

The literature provides weak evidence to support a causal relationship between exit-site infection and subsequent peritonitis. Few criteria for causation were met. We were unable to attribute causation and could assume an association only. The exclusion of studies focusing on PD-related tunnel infections may be viewed as both a strength and a limitation of the present work.

Prevention of peritonitis in peritoneal dialysis

Reducing the frequency of peritonitis for patients undergoing peritoneal dialysis (PD) continues to be a challenge. This review focuses on recent updates in catheter care and other patient factors that influence infection rates. An experienced nursing staff plays an important role in teaching proper PD technique to new patients, but nursing staff must be cognizant of each patient's unique educational needs. Over time, many patients become less adherent to proper dialysis technique, such as washing hands or wearing a mask. This behavior is associated with higher risk of peritonitis and is modifiable with re-training. Prophylactic antibiotics before PD catheter placement can decrease the infection risk immediately after catheter placement. In addition, some studies suggest that prophylaxis against fungal superinfection after antibiotic exposure is effective in reducing fungal peritonitis, although larger randomized studies are needed before this practice can be recommended for all patients. Over time, exit site and nasal colonization with pathogenic organisms can lead to exit-site infections and peritonitis. For patients with Staphylococcus aureus colonization, exit-site prophylaxis with either mupirocin or gentamicin cream reduces clinical infection with this organism. Although there are limited data for support, antibiotic prophylaxis before gastrointestinal, gynecologic, or dental procedures may also help reduce the risk of peritonitis.

Clinical characteristics and outcomes of peritoneal dialysis-related peritonitis with different trends of change in effluent white cell count: a longitudinal study

BACKGROUND

Effluent white cell count (WCC) is among the important prognostic factors for peritonitis outcome, but its trend has never been studied. We aimed to explore the clinical characteristics and outcomes of peritonitis episodes having different trends in effluent WCC change in the first 5 days.

METHODS

For each peritonitis episode, we examined the patient's demographic and biochemical data, serial effluent WCC, and organisms cultured. Peritonitis-associated death and transfer to hemodialysis were defined as treatment failure.

RESULTS

Based on the trend of effluent WCC in the first 5 days, we divided 190 peritonitis episodes into group A (WCC persistently declined), group B (WCC declined after a transient increase), group C (WCC increased after a transient decline), and group D (WCC persistently increased). In group A, peritonitis was caused mostly by gram-positive organisms, and effluent WCC declined the most quickly, leading to a good prognosis. Although the elevation of effluent WCC was prolonged in group B, and the infections were, compared with those in group A, more often caused by gram-negative organisms, outcomes were not worse. In group C, the effluent WCC was more likely to be higher than 100/μL on day 5, and the infection was, compared with those in groups A and B, less likely to be caused by gram-positive organisms. Accordingly, membership in group C independently predicted the worst outcome of peritonitis even adjusted for age, sex, and causative organism.

CONCLUSIONS

Different trends of change in effluent WCC during the early stage of peritonitis represent different clinical patterns and outcomes. Further investigation for optimizing outcomes is required.

The potential role of HMGB1 release in peritoneal dialysis-related peritonitis

High mobility group box 1 (HMGB1), a DNA-binding nuclear protein, has been implicated as an endogenous danger signal in the pathogenesis of infection diseases. However, the potential role and source of HMGB1 in the peritoneal dialysis (PD) effluence of patients with peritonitis are unknown. First, to evaluate HMDB1 levels in peritoneal dialysis effluence (PDE), a total of 61 PD patients were enrolled in this study, including 42 patients with peritonitis and 19 without peritonitis. Demographic characteristics, symptoms, physical examination findings and laboratory parameters were recorded. HMGB1 levels in PDE were determined by Western blot and ELISA. The concentrations of TNF-α and IL-6 in PDE were quantified by ELISA. By animal model, inhibition of HMGB1 with glycyrrhizin was performed to determine the effects of HMGB1 in LPS-induced mice peritonitis. In vitro, a human peritoneal mesothelial cell line (HMrSV5) was stimulated with lipopolysaccharide (LPS), HMGB1 extracellular content in the culture media and intracellular distribution in various cellular fractions were analyzed by Western blot or immunofluorescence. The results showed that the levels of HMGB1 in PDE were higher in patients with peritonitis than those in controls, and gradually declined during the period of effective antibiotic treatments. Furthermore, the levels of HMGB1 in PDE were positively correlated with white blood cells (WBCs) count, TNF-α and IL-6 levels. However, pretreatment with glycyrrhizin attenuated LPS-induced acute peritoneal inflammation and dysfunction in mice. In cultured HMrSV5 cells, LPS actively induced HMGB1 nuclear-cytoplasmic translocation and release in a time and dose-dependent fashion. Moreover, cytosolic HMGB1 was located in lysosomes and secreted via a lysosome-mediated secretory pathway following LPS stimulation. Our study demonstrates that elevated HMGB1 levels in PDE during PD-related peritonitis, at least partially, from peritoneal mesothelial cells, which may be involved in the process of PD-related peritonitis and play a critical role in acute peritoneal dysfunction.

The association between exit site infection and subsequent peritonitis among peritoneal dialysis patients

BACKGROUND AND OBJECTIVES

Peritonitis is the most common infectious complication seen in peritoneal dialysis (PD). Traditionally, exit site infection (ESI) has been thought to predispose PD patients to peritonitis, although the risks have not been quantified. This study aimed to quantify the risk of PD peritonitis after ESI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from 203 clinically stable PD patients >18 years of age who were followed as part of a randomized controlled trial over 18 months were used to estimate the risk of developing peritonitis within 30 days of an ESI compared with individuals who did not have a recent ESI. Sensitivity analyses were performed at 15, 45, and 60 days.

RESULTS

Patients were mostly male (64.5%) and Caucasian, with a mean age of 60.5 ± 14.4 years. There were 44 ESIs and 87 peritonitis episodes during the 18-month study. Seven patients had an ESI followed by peritonitis within 30 days. Using a frailty model, patients who had an ESI had a significantly higher risk of developing peritonitis within 30 days, even if the ESI was appropriately treated. This risk was maximal early on and diminished with time, with hazard ratios (95% confidence interval) of 11.1 at 15 days (HR=11.1, 95% CI=4.9-25.1), 5.3 at 45 days (2.5-11.3), and 4.9 at 60 days (2.4-9.9). In 2.3% of patients, subsequent peritonitis was caused by the same organism as the previous ESI.

CONCLUSIONS

A strong association between a treated ESI and subsequent PD peritonitis was present up to 60 days after initial diagnosis.

Avoiding harm in peritoneal dialysis patients

This review is focused on minimizing complications and avoiding harm in peritoneal dialysis (PD) patients. Issues related to planning for PD are covered first, with emphasis on PD versus hemodialysis outcomes. Catheter types and insertion techniques are described next, including relevant recommendations by the International Society for Peritoneal Dialysis. A brief review of both noninfectious and infectious complications follows, with emphasis on cardiovascular and metabolic complications. Finally, recommendations for preventing PD-related infections are provided. In conclusion, with proper catheter insertion technique, good training, and attention to detail during the tenure in PD, excellent outcomes can be obtained in a well-informed motivated patient.

Polymicrobial peritonitis following colonoscopic polypectomy in a peritoneal dialysis patient

Patients undergoing continuous ambulatory peritoneal dialysis (CAPD) are at an increased risk of peritonitis following colonoscopy with or without polypectomy. Guidelines for peritoneal dialysis patients recommend administration of prophylactic antibiotics and drainage of the abdomen before colonoscopy. In this report, we describe a 53-year-old woman on CAPD who underwent colonoscopy with polypectomy and developed peritonitis within 24 hours. She presented with severe abdominal pain, typical rebounding tenderness, and turbid dialysate containing increased white blood cells with a predominance of neutrophils. A culture of the patient's peritoneal fluid grew polymicrobial species including Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. She was treated with intraperitoneal and intravenous administration of combination antibiotics, and she fully recovered within 3 weeks. We suggest that nephrologists and endoscopists should be familiar with the risks and follow the guidelines to prevent such complications in CAPD patients. If peritonitis occurs, medical therapy with antibiotics should be considered before surgical intervention for catheter salvage.