Microbiology and outcomes of peritonitis in Australian peritoneal dialysis patients

Repeated Peritonitis in a Peritoneal Dialysis Patient: An Unusual Case of Bacillus licheniformis With Vancomycin Failure Despite Sensitivity

Bacillus licheniformis (B. licheniformis) is an aerobic, gram-positive, spore-forming rod typically found in soil, decaying organic matter, vegetables, and water, and occasionally part of normal gut flora. This report highlights a case of unusual repeated peritonitis caused by B. licheniformis, with three episodes occurring over six months, all of which were sensitive to vancomycin yet presented an unclear cause for recurrence. Peritonitis represents a significant cause of mortality, hospitalization, and failure of peritoneal dialysis catheters, leading to forced transitions to hemodialysis. The rarity of B. licheniformis as a pathogen in human infections emphasizes the critical need for precise microbial identification and customized therapeutic strategies.

Peritoneal dialysis related peritonitis: insights from a long-term analysis of an Italian center

BACKGROUND

Peritonitis is a common and severe complication of peritoneal dialysis (PD). For comparative analysis standardized definitions as well as measurements and outcomes are crucial. However, most PD-related peritonitis studies have been using heterogenous definitions and variable methods to measure outcomes. The ISPD 2022 guidelines have revised and clarified numerous definitions and proposed new peritonitis categories and outcomes.

METHODS

Between 1st January 2009 and 31st May 2023, 267 patients who started PD at our institution were included in the study. All PD-related peritonitis episodes that occurred in our unit during the study period were collected. The new definitions and outcomes of ISPD 2022 recommendations were employed.

RESULTS

The overall peritonitis rate was 0.25 episode/patient year. Patient cumulative probability of remaining peritonitis-free at one year was 84.2%. The medical cure and refractory peritonitis rates were equal to 70.3 and 22.4%, respectively. Culture-negative peritonitis accounted for 25.6% of all specimens. The rates of peritonitis associated death, hemodialysis transfer, catheter removal and hospitalization were 6.8%, 18.3%, 18.7% and 64.4%, respectively. Relapsing, repeat, recurrent and enteric peritonitis accounted for 7.8%, 6.8%, 4.1% and 2.7% of all episodes, respectively. Catheter insertion, catheter related and pre-PD peritonitis were 4.2, 2.1 and 0.5%.

CONCLUSIONS

The implementation of PD-related peritonitis reports using standardized definitions and outcome measurements is of paramount importance to enhance clinical practice and to allow comparative studies.

Staphylococcus aureus small colony variants: A potentially underestimated microbiological challenge in peritoneal dialysis

INTRODUCTION

Peritonitis remains the major infectious complication in the setting of peritoneal dialysis (PD). Despite known only moderate pathogenicity, the most frequently detected pathogens in PD-related peritonitis are surprisingly coagulase-negative staphylococci. However, this could be explained, at least in part, by Staphylococcus aureus small colony variants (SCVs) induced by PD fluids (PDFs) and misidentified by routinely used microbiological methods.

MATERIAL AND METHODS

Bacteria were exposed to commonly used PDFs in various regimens designed to simulate daily use as closely as possible. Wild-type isolates and SCVs were subsequently used to determine minimum inhibitory concentrations (MICs), in vitro biofilm formation capacities, and auxotrophies. Underlying genetic alterations were investigated using whole-genome sequencing, and various microbial identification methods were tested to determine their performance for wild-types and SCVs.

RESULTS

Stable SCVs could be isolated most successfully after exposure to glucose-containing PDFs alone. The reading of MICs was significantly affected by the reduced growth of SCVs, resulting in lower MIC values in 44% of all tests. Nonsynonymous mutations were found in all but one SCV, while only two isolates showed typical auxotrophic responses. While MALDI-TOF, PCR and Pastorex Staph-Plus correctly identified all S. aureus SCVs, API-Staph and VITEK-2 yielded identification rates of only 40% and 10%, respectively.

CONCLUSIONS

Overall, the present study has shown that commercially available PDFs induce S. aureus SCVs in vitro, which are difficult to identify and test for antimicrobial susceptibility and can potentially lead to recurrent or persistent infections. Thus, they represent a potentially underappreciated challenge not only for microbiologists, but also for clinicians.

Home-Based Dialysis: A Primer for the Internist

Home-based dialysis modalities offer both clinical and practical advantages to patients. The use of the home-based modalities, peritoneal dialysis and home hemodialysis, has been increasing over the past decade after a long period of decline. Given the increasing frequency of use of these types of dialysis, it is important for clinicians to be familiar with how these types of dialysis are performed and key clinical aspects of care related to their use in patients with end-stage kidney disease.

A Case of Successfully Treated Roseomonas mucosa-induced Peritonitis Diagnosed by Mass Spectrometry

Roseomonas mucosa is difficult to identify using routine analytical techniques. We herein report a case of peritoneal dialysis (PD)-related peritonitis caused by R. mucosa identified using matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS). A 70-year-old woman was admitted to our hospital with PD-related peritonitis. Blood agar medium of dialysate culture derived colony pale pink in color, and the organism was identified as R. mucosa using MALDI-TOF MS. She was successfully treated with ciprofloxacin and meropenem without catheter removal. To our knowledge, this is the first case of R. mucosa peritonitis in which technique failure has been avoided.

Connection assist devices for peritoneal dialysis

Patients with kidney failure who require kidney replacement therapy (KRT) have been increasing globally. Home-based therapies, such as peritoneal dialysis (PD), allow patients to undergo KRT in the home environment, alleviating treatment costs, patient transport, and hospital admission. Peritoneal dialysis-related peritonitis is still the most frequent complication of PD and is often related to technique failure, which can result in PD failure, transfer to hemodialysis, or mortality. The cause of technique failure is multifactorial, and a portion of technique failure is due to underlying physical or cognitive disabilities. There are several connection devices that have been developed to reduce CAPD-related peritonitis. These connection devices are reviewed in this article.

The impact of cat-related peritonitis on peritoneal dialysis outcomes: Results from the RDPLF

BACKGROUND

Cat ownership is common in peritoneal dialysis (PD) patients, even with recent guidelines recommending avoiding domestic animals during PD exchanges to limit the risk of peritonitis due to pet contamination. We analysed the outcomes of patients who experienced cat-related peritonitis compared with those who experienced peritonitis due to other causes.

METHODS

This retrospective study based on the Registre de Dialyse Peritoneale de Langue Française data analysed the outcomes of 52 patients experiencing cat-related peritonitis from the beginning of the database (1986) until 21 June 2022 compared with those of 208 matched patients experiencing peritonitis due to other causes. A Cox regression model examined the association between cat-related peritonitis and the composite end point of death in PD or transfer to haemodialysis (HD), death in PD and transfer to HD.

RESULTS

Among patients with an episode of cat-related peritonitis, 11 (21.1%) died, 19 (36.5%) were transferred to HD and 11 (21.1%) were transplanted. In the group with other causes of peritonitis, these numbers were 67 (32%), 81 (39%) and 26 (12.5%), respectively. In multivariate survival analysis, age (hazard ratio (HR): 1.39; 95% confidence interval (CI): 1.13-1.70) and use of assisted PD (HR: 4.07; 95% CI: 2.11-7.86) were associated with the risk of death. Having experienced cat-related peritonitis was not significantly associated with any of the three outcomes (death, transfer to HD or PD cessation).

CONCLUSIONS

Patients on PD should be aware that cats may cause a peritoneal infection, which results in similar consequences to those of other causes of peritonitis. However, pets at home should not be considered a contraindication to PD.

Comparison of clinical outcomes between culture-negative and positive peritonitis in patients undergoing maintenance peritoneal dialysis: a prospective cohort study

BACKGROUND

Culture-negative peritonitis is a serious complication in patients undergoing maintenance peritoneal dialysis (PD) and occurs in up to 40% of all peritonitis episodes. Despite its high incidence, data regarding treatment response and prognosis remain poorly defined. This study compared the clinical outcomes of patients with culture-negative and positive peritonitis.

METHOD

This prospective cohort study was conducted between 2021 and 2022. Patients treated with maintenance PD who developed PD-associated peritonitis were included and received standard treatment. The primary endpoint was the primary response (resolution of peritonitis 10 days after the initiation of treatment).

RESULTS

Of the 81 patients who developed PD-associated peritonitis during the study, 35 and 46 had culture-negative and culture-positive peritonitis, respectively. Overall, 52 (64.2%) patients achieved the primary response: 24 (68.6%) in the culture-negative group and 28 (60.9%) in the culture-positive group (p = 0.630). There were no significant differences between the two groups in the incidence of complete cure (complete resolution of peritonitis without the need for Tenckhoff catheter removal or salvage antibiotic therapy or peritonitis within 120 days after treatment) (culture-negative vs. culture-positive group, 57.1% vs. 45.7%), refractory peritonitis (28.6% vs. 41.3%), relapse peritonitis (8.6% vs. 2.2%), repeat peritonitis (11.4% vs. 10.9%), salvage antibiotics (40.0% vs. 50.0%), permanent hemodialysis transfer (11.4% vs. 10.9%), Tenckhoff catheter removal (25.7% vs. 41.3%), or mortality (2.9% vs. 2.2%) (all p > 0.05).

CONCLUSION

This study offers valuable insights into the clinical outcomes of culture-negative peritonitis versus culture-positive peritonitis. However, caution must be exercised in interpreting these findings due to the limitations of the small sample size.

CLINICAL TRIAL REGISTRATION

The study was retrospectively registered in the Thai Clinical Trials Registry (TCTR20221130006).

Multi-center, pragmatic, cluster-randomized, controlled trial of standardized peritoneal dialysis (PD) training versus usual care on PD-related infections (the TEACH-PD trial): trial protocol

BACKGROUND

Peritoneal dialysis (PD)-related infections, such as peritonitis, exit site, and tunnel infections, substantially impair the sustainability of PD. Accordingly, PD-related infection is the top-priority research outcome for patients and caregivers. While PD nurse trainers teach patients to perform their own PD, PD training curricula are not standardized or informed by an evidentiary base and may offer a potential approach to prevent PD infections. The Targeted Education ApproaCH to improve Peritoneal Dialysis outcomes (TEACH-PD) trial evaluates whether a standardized training curriculum for PD nurse trainers and incident PD patients based on the International Society for Peritoneal Dialysis (ISPD) guidelines reduces PD-related infections compared to usual training practices.

METHODS

The TEACH-PD trial is a registry-based, pragmatic, open-label, multi-center, binational, cluster-randomized controlled trial. TEACH-PD will recruit adults aged 18 years or older who have not previously undergone PD training at 42 PD treatment units (clusters) in Australia and New Zealand (ANZ) between July 2019 and June 2023. Clusters will be randomized 1:1 to standardized TEACH-PD training curriculum or usual training practice. The primary trial outcome is the time to the first occurrence of any PD-related infection (exit site infection, tunnel infection, or peritonitis). The secondary trial outcomes are the individual components of the primary outcome, infection-associated catheter removal, transfer to hemodialysis (greater than 30 days and 180 days), quality of life, hospitalization, all-cause death, a composite of transfer to hemodialysis or all-cause death, and cost-effectiveness. Participants are followed for a minimum of 12 months with a targeted average follow-up period of 2 years. Participant and outcome data are collected from the ANZ Dialysis and Transplant Registry (ANZDATA) and the New Zealand Peritoneal Dialysis (NZPD) Registry. This protocol follows the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines.

DISCUSSION

TEACH-PD is a registry-based, cluster-randomized pragmatic trial that aims to provide high-certainty evidence about whether an ISPD guideline-informed standardized PD training curriculum for PD nurse trainers and adult patients prevents PD-related infections.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03816111. Registered on 24 January 2019.

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.

Microbial Profile, Peritoneal Fluid White Blood Cell Count, and Outcome of Peritoneal Dialysis-Related Peritonitis at Indonesian Tertiary Hospital

Introduction

Peritonitis caused by peritoneal dialysis (PD) remains a common complication of continuous ambulatory PD (CAPD). The purpose of this study is to determine the microbial profile in CAPD-related peritonitis, the optimal cutoff of white blood cell (WBC) count, and the percentage of polymorphonuclear (PMN) in CAPD fluid in the prediction of CAPD-related peritonitis, together with the outcome of CAPD-related peritonitis at an Indonesian tertiary hospital. This is a retrospective cohort study of CAPD-related peritonitis patients at Indonesian tertiary hospitals from November 2020 to October 2022.

Methods

Patients with suspected CAPD-related peritonitis who were tested for CAPD fluid culture and WBC count in CAPD fluid were eligible for this study. Patient's diagnosis and outcome obtained from medical records. Differences in clinical outcomes by category of microorganisms were analyzed with Fisher exact test. The Mann-Whitney test and receiver operating characteristic curve were used to determine optimal WBC and PMN cutoff.

Results

This study included 58 patients and 102 episodes of CAPD-related peritonitis. CAPD-related peritonitis was caused by 29.4% Gram-negative bacteria, 21.5% Gram-positive bacteria, 7.8% fungi, and 6.9% polymicrobial bacteria. CAPD fluid WBC count >79 cells/μL and PMN percentage >50% had a sensitivity of 76.4% and a specificity of 92.9% in predicting CAPD-related peritonitis. There was a significant difference in outcome between Gram-negative and Gram-positive bacterial peritonitis.

Conclusions

It is critical to understand the microbial profile in CAPD-related peritonitis. Lower WBC count cutoff points in CAPD fluids may improve sensitivity in predicting CAPD-related peritonitis.

Peritoneal dialysis-related peritonitis with encapsulated ascites due to Mycobacterium abscessus subsp. massilience and subsp. bolletii: a case series and literature review

Background

As there is no established standard of care for non-tuberculous mycobacterium (NTM) peritoneal dialysis (PD)-related peritonitis, its treatments have to be case-dependent, which is often difficult. Additionally, several reported cases were accompanied by encapsulated ascites, adhesive ileus, and encapsulating peritoneal sclerosis, suggesting treatment difficulties. We report two cases of PD-related peritonitis with encapsulated ascites due to Mycobacterium abscessus subsp. massilience and subsp. bolletii. To the best of our knowledge, this is the first case series to report PD-related peritonitis caused by Mycobacterium abscessus subsp. bolletii.

Case presentation

The first case is that of a 74-year-old male patient who started PD six years ago for end-stage renal failure due to diabetic nephropathy. In February 2021, he presented with signs of infection at the exit-site and swelling of the tunnel. Mycobacterium abscessus subsp. massilience was detected in the culture of the exit-site exudate; thus, he was diagnosed with tunnel infection (caused by NTM). Subsequently, fever, abdominal pain, and increased cell counts in the PD drainage fluid were observed, and he was judged to have NTM peritonitis. His general condition improved after PD catheter removal in addition to antimicrobial treatment and encapsulated ascites drainage. The second case is that of a 52-year-old man who commenced PD for end-stage renal failure due to nephrosclerosis 12 years ago. In May 2022, he was diagnosed with PD-related peritonitis based on signs of infection at the exit-site, encapsulated ascites on computed tomography, and a cloudy PD drainage fluid. Mycobacterium abscessus subsp. bolletii was detected in the culture of the exit-site exudate, which led to the diagnosis of NTM peritonitis. In addition to antimicrobial treatment, PD catheter removal and encapsulated ascites drainage were performed. The patient also had adhesive bowel obstruction due to peritonitis and required decompression therapy with the insertion of a gastric tube.

Conclusions

PD catheter removal and encapsulated ascites drainage might have improved inflammation and treatment outcomes. Additionally, Mycobacterium abscessus might be prone to forming encapsulated cavities and/or intestinal adhesions; however, further accumulation of cases clarifying “subspecies” of Mycobacterium abscessus is necessary to confirm this hypothesis.

Hypokalemia Duration in the First Year Associated with Subsequent Peritoneal Dialysis-Associated Peritonitis: A Multicenter Retrospective Cohort Study

BACKGROUND

The association of hypokalemia (LK) with peritoneal dialysis-associated peritonitis (PDAP) risk remains uncertain. Here, we calculated LK duration in the first PD year and evaluated its association with PDAP.

METHODS

A multicenter, retrospective, incident cohort study of 1633 participants was conducted from January 2008 to October 2020 in China. The duration of LK and severe hypokalemia (SLK) was calculated as the total number of months that a patient's serum potassium (SK) level was less than 3.5 or 3.0 mEq/L during the first PD year. The study outcome was the risk of subsequent PDAP started in the second year and later. Cox proportional hazards models and competing risk models were used to assess the association.

RESULTS

The subsequent PDAP occurred in 420 (25.7%) participants during a median of 28 months of follow-up. Overall, LK duration in the first year was positively associated with a subsequent PDAP risk (per 3-month increments, adjusted HR, 1.13; 95%CI: 1.05-1.23). After categorization, patients with LK duration longer than 6 months had the highest adjusted HR of 1.53 (p = 0.005 vs. those without LK) for subsequent PDAP risk. A similar trend was also found for SLK duration. In a competing risk model, a similar trend was also observed. None of the variables, including demographic and PD characteristics, diabetes history, and several clinical measurements, significantly modified this association. The causative organisms of PDAP were similar to those previously reported.

CONCLUSIONS

PD patients with longer LK duration in the first year had a higher subsequent PDAP risk.

Proton pump inhibitor usage associates with higher risk of first episodes of pneumonia and peritonitis in peritoneal dialysis patients

Background

A large number of studies have shown that proton pump inhibitors (PPIs) are associated with infection events. Therefore, we retrospectively evaluated the association of PPI therapy with the occurrence of first pneumonia and peritoneal dialysis(PD)-related peritonitis events in the maintenance PD patients.

Methods

We collected PD patients in two large hospitals from January 1, 2012 to December 31, 2016, and divided them into the PPI group and the non-PPI group. Multivariate Cox proportional hazards models were applied to evaluate the cumulative incidence and hazard ratios (HRs). Inverse probability of treatment weight (IPTW) method was used to adjust for covariate imbalance between the two groups and further confirm our findings.

Results

Finally, 656 PD patients were included for data analysis, and the results showed that PPI usage was associated with an increased risk of pneumonia [HR 1.71; 95% CI 1.06-2.76; p = 0.027] and peritonitis [HR 1.73; 95% CI 1.24-2.40; p = 0.001]. IPTW-adjusted HRs for the association of PPIs with pneumonia and peritonitis were 1.58 (95% CI:1.18-2.12; p = 0.002) and 2.33 (95% CI:1.91-2.85; p < 0.001), respectively. Moreover, the competitive risk model proved that under the conditions of competition for other events(including transfer to hemodialysis therapy, kidney transplant, transfer from our research center, loss to follow-up, and death), the differences in endpoints events between the two groups were still statistically significant (p = 0.009, p < 0.001, respectively).

Conclusions

PPIs was associated with an increased risk of first pneumonia and PD-related peritonitis events in PD patients, which reminds clinicians to be cautious when prescribing acid-suppressing drugs for PD patients.

Intervention Mechanism of Niao Du Kang Mixture on the EMT Process of Peritoneal Fibrosis Based on the Wnt/β-Catenin Signaling Pathway

Methods

Quantification of 24-hour urine protein (24 h-Upro) and serum creatinine (Scr) levels was performed. The protein and mRNA expression levels of E-cadherin, α-SMA, collagen I, β-catenin, Wnt-1, and LEF-1 in peritoneal tissue were measured. In addition, the pathological morphology and ultrastructure of peritoneum were observed.

Results

After 5/6 nephrectomy + high glucose peritoneal dialysate + lipopolysaccharide (LPS) treatment, the Scr and 24 h-Upro of rats increased compared with normal rats, and the peritoneal tissue was damaged and thickened, showing fibrotic changes. Compared with the model group, the Scr and 24 h-Upro levels and the levels of E-cadherin, α-SMA, Wnt-1, collagen I, and LEF-1 protein expression in each Niao Du Kang mixture dosage group decreased. The protein expression of β-catenin and the mRNA expression of E-cadherin, α-SMA, Wnt-1, collagen I, β-catenin, and LEF-1 decreased in the high and medium Niao Du Kang mixture dose groups. Hematoxylin and eosin staining showed that the peritoneum of the rats was not only thicker in the model group than in the sham operation group (P < 0.01) but also accompanied by apparent inflammatory cell infiltration, tissue edema, and fibrosis. Compared with the model group, all the Niao Du Kang mixture groups demonstrated various degrees of mitigation in peritoneal thickness and fibrosis (P < 0.01). The strongest effect was observed in the medium-dose group. Transmission electron microscopy showed that the degree of injury of the peritoneal mesothelial cells was ranked as follows: model group > positive drug group > Niao Du Kang mixture high-dose group.

Conclusions

The Niao Du Kang mixture may effectively decrease the peritoneal thickness and fibrosis degree through its effect on the Wnt/β-catenin signaling pathway involved in EMT. The present study provides data that assist in elucidating the potential function of the Niao Du Kang mixture in treating or preventing PF.

Microbiology and outcomes of polymicrobial peritonitis associated with peritoneal dialysis: a register-based cohort study from the French Language Peritoneal Dialysis Registry (RDPLF)

BACKGROUND

Previous studies have reported that polymicrobial peritonitis in peritoneal dialysis (PD) is associated with poor outcomes, but recent data from European cohorts are scarce.

METHODS

We included from the French Language Peritoneal Dialysis Registryall patients ≥ 18 years who started PD between January 2014 and November 2020. We compared microbiology and patient characteristics associated with mono- and polymicrobial peritonitis. We assessed patient outcomes after a first polymicrobial peritonitis using survival analysis with competing events. We differentiated microorganisms isolated from dialysis effluent as enteric or non-enteric pathogens.

RESULTS

8848 patients contributed 13 023 patient-years of follow-up and 3348 culture-positive peritonitis, including 251 polymicrobial ones. This corresponded to rates of 0.32 and 0.02 episodes/patient-year, respectively. For most patients (72%) who experienced polymicrobial peritonitis, this was their first peritonitis episode. Enteric pathogens were more frequently isolated in poly- than in monomicrobial peritonitis (57 vs 44%, P < 0.001). In both cases of peritonitis with or without enteric pathogens, the poly- versus monomicrobial character of the peritonitis was not associated with mortality in patients who did not switch to hemodialysis (adjusted cause-specific hazard ratio, a.cs-HR, 1.2 [95% CI, 0.3-5.0], P = 0.78 and 1.1 [0.7-1.8], P = 0.73, respectively). However, the risks of death and switch to hemodialysis were higher for monomicrobial peritonitis with enteric pathogens, compared to those without (a.cs-HR, 1.3 [1.1-1.7], P = 0.02 and 1.9 [1.5-2.4], P < 0.0001, respectively).

CONCLUSION

Isolation of enteric pathogens, rather than the polymicrobial character of the peritonitis, is associated with poorer outcomes.

Epidemiology of peritoneal dialysis outcomes

Peritoneal dialysis (PD) is an important home-based treatment for kidney failure and accounts for 11% of all dialysis and 9% of all kidney replacement therapy globally. Although PD is available in 81% of countries, this provision ranges from 96% in high-income countries to 32% in low-income countries. Compared with haemodialysis, PD has numerous potential advantages, including a simpler technique, greater feasibility of use in remote communities, generally lower cost, lesser need for trained staff, fewer management challenges during natural disasters, possibly better survival in the first few years, greater ability to travel, fewer dietary restrictions, better preservation of residual kidney function, greater treatment satisfaction, better quality of life, better outcomes following subsequent kidney transplantation, delayed need for vascular access (especially in small children), reduced need for erythropoiesis-stimulating agents, and lower risk of blood-borne virus infections and of SARS-CoV-2 infection. PD outcomes have been improving over time but with great variability, driven by individual and system-level inequities and by centre effects; this variation is exacerbated by a lack of standardized outcome definitions. Potential strategies for outcome improvement include enhanced standardization, monitoring and reporting of PD outcomes, and the implementation of continuous quality improvement programmes and of PD-specific interventions, such as incremental PD, the use of biocompatible PD solutions and remote PD monitoring.

The use of peritoneal dialysis (PD) can be advantageous compared with haemodialysis treatment, although several barriers limit its broad implementation. This review examines the epidemiology of peritoneal dialysis (PD) outcomes, including clinical, patient-reported and surrogate PD outcomes.

Peritoneal dialysis (PD) has distinct advantages compared with haemodialysis, including the convenience of home treatment, improved quality of life, technical simplicity, lesser need for trained staff, greater cost-effectiveness in most countries, improved equity of access to dialysis in resource-limited settings, and improved survival, particularly in the first few years of initiating therapy.

Important barriers can hamper PD utilization in low-income settings, including the high costs of PD fluids (owing to the inability to manufacture them locally and the exorbitant costs of their import), limited workforce availability and a practice culture that limits optimal PD use, often leading to suboptimal outcomes.

PD outcomes are highly variable around the world owing in part to the use of variable outcome definitions, a heterogeneous practice culture, the lack of standardized monitoring and reporting of quality indicators, and kidney failure care gaps (including health care workforce shortages, inadequate health care financing, suboptimal governance and a lack of good health care information systems).

Key outcomes include not only clinical outcomes (typically defined as medical outcomes based on clinician assessment or diagnosis) — for example, PD-related infections, technique survival, mechanical complications, hospitalizations and PD-related mortality — but also patient-reported outcomes. These outcomes are directly reported by patients and focus on how they function or feel, typically in relation to quality of life or symptoms; patient-reported outcomes are used less frequently than clinical outcomes in day-to-day routine care.

Predictors and outcomes of peritoneal dialysis-related infections due to filamentous molds (MycoPDICS)

Introduction

We sought to evaluate the predictors and outcomes of mold peritonitis in patients with peritoneal dialysis (PD).

Methods

This cohort study included PD patients from the MycoPDICS database who had fungal peritonitis between July 2015-June 2020. Patient outcomes were analyzed by Kaplan Meier curves and the Log-rank test. Multivariable Cox proportional hazards model regression was used to estimating associations between fungal types and patients’ outcomes.

Results

The study included 304 fungal peritonitis episodes (yeasts n = 129, hyaline molds n = 122, non-hyaline molds n = 44, and mixed fungi n = 9) in 303 patients. Fungal infections were common during the wet season (p <0.001). Mold peritonitis was significantly more frequent in patients with higher hemoglobin levels, presentations with catheter problems, and positive galactomannan (a fungal cell wall component) tests. Patient survival rates were lowest for non-hyaline mold peritonitis. A higher hazard of death was significantly associated with leaving the catheter in-situ (adjusted hazard ratio [HR] = 6.15, 95%confidence interval [CI]: 2.86–13.23) or delaying catheter removal after the diagnosis of fungal peritonitis (HR = 1.56, 95%CI: 1.00–2.44), as well as not receiving antifungal treatment (HR = 2.23, 95%CI: 1.25–4.01) or receiving it for less than 2 weeks (HR = 2.13, 95%CI: 1.33–3.43). Each additional day of antifungal therapy beyond the minimum 14-day duration was associated with a 2% lower risk of death (HR = 0.98, 95%CI: 0.95–0.999).

Conclusion

Non-hyaline-mold peritonitis had worse survival. Longer duration and higher daily dosage of antifungal treatment were associated with better survival. Deviations from the 2016 ISPD Peritonitis Guideline recommendations concerning treatment duration and catheter removal timing were independently associated with higher mortality.

ISPD peritonitis guideline recommendations: 2022 update on prevention and treatment

Peritoneal dialysis (PD)-associated peritonitis is a serious complication of PD and prevention and treatment of such is important in reducing patient morbidity and mortality. The ISPD 2022 updated recommendations have revised and clarified definitions for refractory peritonitis, relapsing peritonitis, peritonitis-associated catheter removal, PD-associated haemodialysis transfer, peritonitis-associated death and peritonitis-associated hospitalisation. New peritonitis categories and outcomes including pre-PD peritonitis, enteric peritonitis, catheter-related peritonitis and medical cure are defined. The new targets recommended for overall peritonitis rate should be no more than 0.40 episodes per year at risk and the percentage of patients free of peritonitis per unit time should be targeted at >80% per year. Revised recommendations regarding management of contamination of PD systems, antibiotic prophylaxis for invasive procedures and PD training and reassessment are included. New recommendations regarding management of modifiable peritonitis risk factors like domestic pets, hypokalaemia and histamine-2 receptor antagonists are highlighted. Updated recommendations regarding empirical antibiotic selection and dosage of antibiotics and also treatment of peritonitis due to specific microorganisms are made with new recommendation regarding adjunctive oral N-acetylcysteine therapy for mitigating aminoglycoside ototoxicity. Areas for future research in prevention and treatment of PD-related peritonitis are suggested.

Baseline Peritoneal Membrane Transport Characteristics Are Associated with Peritonitis Risk in Incident Peritoneal Dialysis Patients

The peritoneal equilibration test (PET) is a semi-quantitative measurement that characterizes the rate of transfer of solutes and the water transfer rate across the peritoneum in patients treated with peritoneal dialysis (PD). The results of the PET are used to maximize daily peritoneal ultrafiltration and solute clearances. Previous studies have shown that high transport status is associated with ultrafiltration failure, malnutrition, and reduced survival; however, the way in which peritoneum transport characteristics affect peritonitis risk is unknown. In the current cohort study, we recruited 898 incident-PD patients and used intention-to-treat analysis to test if baseline PET affected the subsequent 3-year peritonitis rate. Among all recruited PD patients, 308 (34.2%) developed peritonitis within three years. Multivariate Cox regression analysis showed that the high-transport group has the greatest peritonitis risk (HR 1.98, 95% CI: 1.08–3.62) even after an adjustment for demographics, comorbid diseases, and biochemical measurements. We concluded that a baseline high peritoneal membrane transport rate is an independent risk factor for peritonitis in incident PD patients.

The Impact of Preoperative Risk Factors on Peritoneal Dialysis-Related Peritonitis: A Single-Center Prospective Study in Japan

Background and Objectives: Peritoneal dialysis (PD)-related peritonitis is a critical problem. However, preoperative risk factors for PD-related peritonitis have not been established. Thus, we aimed to determine the preoperative risk factors for PD-related peritonitis. Materials and Methods: This is a single-center prospective observational study. All peritonitis episodes during the study period were recorded, and preoperative and intraoperative clinical parameters were compared between patients with and without peritonitis to examine risk factors for PD-related peritonitis. Furthermore, subcutaneous and abdominal fat volumes were evaluated using computed tomography. Results: Among a total of 118 patients, 24 patients developed peritonitis. The proportion of male patients (83% vs. 61%, p = 0.04), body mass index (25 vs. 22 kg/m², p = 0.04), and subcutaneous fat area (120 vs. 102 cm², p = 0.01) were significantly higher and the proportion of patients living with family members (75% vs. 94%, p = 0.02) was significantly lower in the peritonitis group than in the non-peritonitis group. There were no significant differences in age, operation method, surgeon experience, previous abdominal surgery, medical history of diabetic nephropathy, serum albumin level, and renal function between the two groups. Conclusions: Male patients with high subcutaneous fat who are living alone might be at higher risk of PD-related peritonitis. These characteristics might be useful in risk assessment and patient education before PD induction.

Peritoneal Dialysis-Related Peritonitis: Rate, Clinical Outcomes and Patient Survival

Peritoneal dialysis-related peritonitis remains the major complication and primary challenge to the long-term success of peritoneal dialysis (PD). The study aimed to analyze the peritonitis rate, the cause, the outcomes, and the association of peritonitis with the survival of patients on peritoneal dialysis. Patient data were collected retrospectively from medical charts. A total of 96 patients received peritoneal dialysis in the PD center from 1 January 1999 to 31 December 2018. Episodes of peritonitis (n=159) were registered in 54 (56.3%) patients. The study population was divided into two groups, a group of patients (n=54) who experienced peritonitis and a group of patients free of peritonitis (n=42). The peritonitis rate was 0.47 episodes per patient year. The majority of causative microorganisms were gram-positive bacteria (53.5%). Outcomes of the episodes of peritonitis were resolved infection in 84.9% of episodes, catheter removal in 11.3% of episodes, and death in 3.8% of the episodes of peritonitis. A Kaplan-Meier analysis and log-rank test revealed that the group with peritonitis tended to survive significantly longer than the peritonitis-free group. A 67% reduction rate in the risk of patient mortality was observed for the peritonitis group compared with the peritonitis-free group (hazard ratio: 0.33, 95% CI 0.19-0.57, P=0.000). The prevention and management of PD-related infections, resulted in their worldwide reduction, supporting the use of PD as a first-line dialysis modality.

Peritoneal transport status and first episode of peritonitis: a large cohort study

BACKGROUND

Peritonitis is one of the most serious complications of peritoneal dialysis (PD). This study aimed to explore the relationship between peritoneal transport status and the first episode of peritonitis, as well as the prognosis of patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

METHOD

A retrospective cohort study was conducted, analyzing data of CAPD patients from 1st January 2009, to 31st December 2017. Baseline data within 3 months after PD catheter placement was recorded. Cox multivariate regression analysis was performed to determine the risk factors for the first episode of peritonitis, technique failure and overall mortality.

RESULTS

A total of 591 patients were included in our analysis, with a mean follow-up visit of 49 months (range: 27-75months). There were 174 (29.4%) patients who had experienced at least one episode of peritonitis. Multivariate Cox regression analysis revealed that a higher peritoneal transport status (high and high-average) (HR 1.872, 95%CI 1.349-2.599, p = 0.006) and hypoalbuminemia (HR 0.932,95% CI 0.896, 0.969, p = 0.004) were independent risk factors for the occurrence of the first episode of peritonitis. In addition, factors including gender (male) (HR 1.409, 95%CI 1.103, 1.800, p = 0.010), low serum albumin (HR 0.965, 95%CI 0.938, 0.993, p = 0.015) and the place of residence (rural) (HR 1.324, 95%CI 1.037, 1.691, p = 0.024) were independent predictors of technique failure. Furthermore, low serum albumin levels (HR 0.938, 95%CI 0.895, 0.984, p = 0.008) and age (>65years) (HR 1.059, 95%CI 1.042, 1.076, p < 0.001) were significantly associated with the risk of overall mortality of PD patients.

CONCLUSIONS

Baseline hypoalbuminemia and a higher peritoneal transport status are risk factors for the first episode of peritonitis. Factors including male gender, hypoalbuminemia, and residing in rural areas are associated with technique failure, while hypoalbuminemia and age (>65years) are predictors of the overall mortality in PD patients. Nevertheless, the peritoneal transport status does not predict technique failure or overall mortality of PD patients.

EDTA and Taurolidine Affect Pseudomonas aeruginosa Virulence In Vitro-Impairment of Secretory Profile and Biofilm Production onto Peritoneal Dialysis Catheters

Peritoneal catheter-associated biofilm infection is reported to be the main cause of refractory peritonitis in peritoneal dialysis patients. The application of antimicrobial lock therapy, based on results on central venous catheters, may be a promising option for treatment of biofilm-harboring peritoneal catheters. This study investigated the effects of two lock solutions, EDTA and taurolidine, on an in vitro model of Pseudomonas aeruginosa biofilm-related peritoneal catheter infection. Silicone peritoneal catheters were incubated for 24 h with a bioluminescent strain of P. aeruginosa. Then, serial dilutions of taurolidine and/or EDTA were applied (for 24 h) once or twice onto the contaminated catheters, and P. aeruginosa viability/persistence were evaluated in real time up to 120 h using a Fluoroskan reader. On selected supernatants, high-performance liquid chromatography mass spectrometry (HPLC-MS) analysis was performed to measure the production of autoinducers (AI), phenazines, and pyocyianines. Taurolidine alone or in combination with EDTA caused a significant decrease of bacterial load and biofilm persistence on the contaminated catheters. The treatment did not lead to the sterilization of the devices, yet it resulted in a substantial destructuration of the catheter-associated P. aeruginosa biofilm. HPLC-MS analysis showed that the treatment of biofilm-harboring catheters with taurolidine and EDTA also affected the secretory activity of the pathogen. EDTA and taurolidine affect P. aeruginosa biofilm produced on peritoneal catheters and profoundly compromise the microbial secretory profile. Future studies are needed to establish whether such lock solutions can be used to render peritoneal catheter-related infections more susceptible to antibiotic treatment. IMPORTANCE An in vitro model allows studies on the mechanisms by which the lock solutions exert their antimicrobial effects on catheter-associated biofilm, thus providing a better understanding of the management of devise-associated infections.

Intraperitoneal pharmacokinetics of vancomycin in patients on automated peritoneal dialysis

It is unclear if the pharmacokinetics of vancomycin are the same during automated peritoneal dialysis (APD), where cycler exchanges may affect the systemic, peritoneal, and urinary disposition of drug. We conducted a prospective pharmacokinetic study evaluating the pharmacokinetics of vancomycin in plasma, dialysis fluid, and urine in peritonitis‐negative patients on APD. Patients underwent four drug‐free exchanges with 1.5% or 2.5% dextrose following the initial dwell period. Plasma, dialysis fluid, and urine was collected over the course of 7 days for pharmacokinetic analysis. Four patients completed the study with no adverse events. Following a median (range) dwell of 14.6 (14.2–17.6 h), the mean (±SD) observed maximum plasma concentration was 28.7 ± 4.9 mg/L with a mean bioavailability of 98.5 ± 1.4% prior to starting the cycler. The overall mean total plasma clearance estimated from study start to completion was 7.6 ± 1.2 ml/min. Mean total clearance during the dialytic exchange was 13.6 ± 4.9 ml/min. In patients with residual renal function, the mean vancomycin renal clearance was 3.1 ± 1.5 ml/min, representing 21.4%–58.9% of the overall total plasma clearance during the study period. Despite the small sample size, this pilot study suggests that the dwell time has important implications for systemic vancomycin exposure, time to therapeutic plasma concentration, and dosing. Dose is driven by dwell time, whereas the cycler determines the dosing interval. Rapid exchanges from APD will determine the frequency of dosing rather than the adequacy of absorption when vancomycin is given in the peritoneum.

Association between the use of exchange devices for peritoneal dialysis fluids and peritonitis incidence: A nationwide cohort study

BACKGROUND

The use of exchange devices for peritoneal dialysis (PD) fluids is a common practice in Japan. Evidence on the effectiveness of exchange devices in preventing PD-related peritonitis is scarce. We evaluated the association between the use of exchange devices for PD fluids and peritonitis incidence.

METHODS

We retrospectively enrolled 3845 patients, aged ≥20 years, receiving PD for ≥3 months, with available data on the exchange procedure for PD fluids and peritonitis incidence that was obtained from the Japan Renal Data Registry, a nationwide annual survey. The patients were grouped according to whether the manual or device PD fluid exchange method was used. The onset of peritonitis was defined as a leukocyte count of >100/µL (neutrophils ≥50%) in PD effluents. We applied quasi-Poisson regression analyses to estimate the incidence rate ratio (IRR). Age, sex, PD vintage, body mass index, automated PD use, residual kidney function, comorbidities, haemoglobin and serum albumin were adjusted as potential confounders.

RESULTS

Older age, automated PD use, diabetes as comorbidity and lower haemoglobin levels were associated with the use of exchange devices for PD fluids. Patients using devices for PD fluid exchange (69.2%) had an increased risk of peritonitis of 37% (IRR: 1.37, 95% confidence interval (CI): 1.07-1.75) and 28% (IRR: 1.28, 95% CI: 1.00-1.63) in the crude and multivariate adjustment models, respectively.

CONCLUSIONS

The use of exchange devices for PD fluids and peritonitis incidence showed no favourable association. There may remain possible residual confounding by indication.

International peritoneal dialysis training practices and the risk of peritonitis

BACKGROUND

The effects of training practices on outcomes of patients receiving peritoneal dialysis (PD) are poorly understood and there is a lack of evidence informing best training practices. This prospective cohort study aims to describe and compare international PD training practices and their association with peritonitis.

METHODS

Adult patients on PD < 3 months participating in the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) were included. Training characteristics (including duration, location, nurse affiliation, modality, training of family members, use of individual/group training, and use of written/oral competency assessments) were reported at patient and facility levels. Hazard ratio for time to first peritonitis was estimated using Cox models, adjusted for selected patient and facility case-mix variables.

RESULTS

1376 PD patients from 120 facilities across 7 countries were included. Training was most commonly performed at the facility (81%), by facility-affiliated nurses (87%) in a 1:1 setting (79%). In the UK, being trained by both facility and third-party nurses was associated with reduced peritonitis risk (aHR 0.31, 95% CI 0.15-0.62, vs facility nurses only). However, this training practice was utilized in only 5 of 14 UK facilities. No other training characteristics were convincingly associated with peritonitis risk.

CONCLUSIONS

There was no evidence to support that peritonitis risk was associated with when, where, how, or how long PD patients are trained.

Impact of assistance on peritonitis due to breach in aseptic procedure in diabetic patients: A cohort study with the RDPLF data

BACKGROUND

Diabetic patients often have physical impairment that could lead to manipulation errors in peritoneal dialysis (PD) and touch contamination. Nurse assistance in diabetic PD patients is known to help prevent peritonitis. We made the hypothesis that this lower risk of peritonitis was observed thanks to prevention of breach in aseptic procedure. We evaluated the impact of nurse-assisted PD on specific causes of peritonitis, especially on peritonitis due to a breach in aseptic procedure.

METHODS

This was a retrospective observational study of the data from the French Language Peritoneal Dialysis Registry. All diabetic patients older than age 18 years starting PD in France between 1 January 2012 and 31 December 2015 were included in the study. The event of interest was the first peritonitis event due to a breach in aseptic procedure. Death, kidney transplantation and peritonitis due to another mechanism were considered as competing events. We examined the association of the covariates with all the possible outcomes using a subdistribution hazard model developed for survival analysis in the presence of competing risks.

RESULTS

Four thousand one hundred one diabetic patients incident in PD were included in the study. At least one peritonitis event occurred in 1611 patients over the study period. A breach in aseptic procedure was reported in 441/1611 cases (27.3%): 209/575 (36.3%) in the self-care PD group, 56/217 (25.8%) in the family-assisted PD group and 176/819 (21.5%) in the nurse-assisted PD group. Both nurse and family assistance were associated with a lower risk of peritonitis due to breach in aseptic procedure in bivariate analysis. After adjustment on age, modified Charlson index, sex and diabetic nephropathy, patients treated by nurse-assisted PD (subdistribution hazard ratio (sd-HR) 0.52, 95% confidence interval (CI) 0.40-0.67) and those treated by family-assisted PD (sd-HR 0.70, 95% CI 0.51-0.95) had a lower likelihood of peritonitis due to a connection error compared to self-care PD in multivariate analysis. The modality of assistance was not associated with other causes of peritonitis in the multivariate analysis.

CONCLUSION

While both nurse-assisted PD and family-assisted PD were associated with lower risk of peritonitis due to a breach in aseptic procedure compared to self-care PD in our study, the protective effect was greater with nurse assistance.

A case of peritoneal dialysis-related peritonitis caused by dialysate leakage with successful treatment by intravenous and intraperitoneal antibiotic therapy

Dialysate leakage is one of the causes of peritoneal dialysis (PD)-related peritonitis. The rate of catheter removal in PD-related peritonitis caused by dialysate leakage (PDPDL) is high, and the correct treatment is unclear. We experienced a case of PDPDL that was treated with intravenous and intraperitoneal antibiotic therapy. A 44-year-old Japanese man had high glucose discharge from the exit site after 14 days of initiating PD, and he had a fever and cloudy effluent with a high white cell count. We diagnosed him with PDPDL and began to administer vancomycin and ceftazidime intraperitoneally. However, the peritonitis could not be ameliorated. A culture examination showed Staphylococcus aureus from the effluent of peritoneal cavity and exit site cultures. We began intraperitoneal cefazolin administration according to a drug susceptibility test, but the effluent cell count remained high. As we added intravenous cefazolin administration, his symptoms and cloudy effluent improved, and the effluent cell count normalized. He has not developed any recurrence of dialysate leakage or peritonitis. Our findings suggest that PD-related peritonitis accompanied by other infectious sites, such as PDPDL, should be treated with additional intravenous antibiotic therapy to taking effect on the infectious sites except for peritoneum and to keep plasma concentration of antibiotics sufficient especially in cases with preserved residual kidney function.

Association between conscientiousness and peritoneal dialysis-related peritonitis

AIM

Peritonitis is a critical complication in patients undergoing peritoneal dialysis. Patient characteristics, especially conscientiousness, potentially influence self-care activity. This study aimed to examine the relationship between the peritonitis risk and the patient conscientiousness.

METHODS

This retrospective observational study was conducted at three Japanese medical centres in 2018. Adult patients undergoing peritoneal dialysis were evaluated for conscientiousness with the Japanese version of the Ten-Item Personality Inventory. We followed the patients from peritoneal dialysis induction retrospectively on chart review. The primary outcome was time to first episode of peritonitis after initiation of peritoneal dialysis in the entire observation period. Hazard ratios were estimated using a Cox model adjusted for potential confounders.

RESULTS

Among 111 patients enrolled, 32 experienced peritonitis. The patients were divided into the more conscientious group (n = 64) and less conscientious group (n = 47) based on a mean conscientiousness score of 3.991. Additionally, less conscientious patients tended to be at higher risk for peritonitis during the entire study period (hazard ratio adjusted for age and sex, 1.99; 95% confidence interval, 0.98-4.03; p = .057). The increased risk in the less conscientious group was statistically significant in the first year (adjusted hazard ratio, 6.98; 95% confidence interval, 1.42-34.40; p = .017).

CONCLUSION

Less conscientious patients significantly have shorter peritonitis-free survival in the early phase after peritoneal dialysis induction although not significantly during the entire study period. Personality trait assessment using the Ten-Item Personality Inventory could be helpful in educating and following up patients undergoing peritoneal dialysis.

Peritoneal Dialysis Guidelines 2019 Part 1 (Position paper of the Japanese Society for Dialysis Therapy)

Approximately 10 years have passed since the Peritoneal Dialysis Guidelines were formulated in 2009. Much evidence has been reported during the succeeding years, which were not taken into consideration in the previous guidelines, e.g., the next peritoneal dialysis PD trial of encapsulating peritoneal sclerosis (EPS) in Japan, the significance of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), the effects of icodextrin solution, new developments in peritoneal pathology, and a new international recommendation on a proposal for exit-site management. It is essential to incorporate these new developments into the new clinical practice guidelines. Meanwhile, the process of creating such guidelines has changed dramatically worldwide and differs from the process of creating what were “clinical practice guides.” For this revision, we not only conducted systematic reviews using global standard methods but also decided to adopt a two-part structure to create a reference tool, which could be used widely by the society’s members attending a variety of patients. Through a working group consensus, it was decided that Part 1 would present conventional descriptions and Part 2 would pose clinical questions (CQs) in a systematic review format. Thus, Part 1 vastly covers PD that would satisfy the requirements of the members of the Japanese Society for Dialysis Therapy (JSDT). This article is the duplicated publication from the Japanese version of the guidelines and has been reproduced with permission from the JSDT.

Two decades of analysis of peritonitis in peritoneal dialysis in Andalusia: Epidemiological, clinical, microbiological and progression aspects

BACKGROUND

This study focuses on the main complication associated with peritoneal dialysis, peritonitis. Its relevance derives from its high morbidity, the negative effect it has on the peritoneum as a dialysis membrane and its financial cost.

METHODS

Analytical, non-interventional, observational cohort study, whose main objective is the analysis of peritonitis in patients on peritoneal dialysis in Andalusia from 1 January 1999 to 31 December 2017, with a total of 2904 peritonitis cases. The database used is the Andalusian Autonomous Transplant Coordination Information System (SICATA).

OBJECTIVES

To ascertain how the rate of peritonitis is evolving in our community, analyse descriptive data pertaining to patients and peritonitis, ascertain the course of these infectious complications and analyse the factors that influence these cases of peritonitis and their outcomes: germ, hospitalisation and date.

RESULTS

The rate of peritonitis decreased progressively during the study period, from 0.7 peritonitis per patient in 1999 to 0.33 at the end of the period. Most infections were treated on an outpatient basis (72.5%). The most common germs were Gram-positive (55.9%), including coagulase-negative staphylococci (28.1%). Most cases of peritonitis progressed to healing (77.8%). The factors that significantly influence the need for hospitalisation and peritonitis progression were the causative germ and associated exit site infection.

CONCLUSIONS

In our population, the rate of peritonitis decreased progressively during the study period, meeting guideline recommendations.

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.

Successful Treatment of Bacillus licheniformis Peritonitis in Peritoneal Dialysis Patient with Intraperitoneal Vancomycin: A Case Report

Bacillus licheniformis is a rare pathogen causing peritonitis in peritoneal dialysis (PD) patients, and it is usually recognized among immunosuppressed or traumatized patients. A 24-year-old lady was treated for peritonitis as an outpatient with empirical therapy. PD culture grew Bacillus licheniformis after 48 hours, and she continued receiving intraperitoneal (IP) vancomycin for a total of three weeks. The patient was clinically stable throughout the course of therapy and showed complete resolution of her symptoms. This was the first case of reported Bacillus peritonitis in an automated peritoneal dialysis (APD) patient with rapid clinical and biochemical improvement without evidence of relapse or recurrence.

Longer antibiotic durations for treating peritoneal dialysis-associated peritonitis: helpful or harmful?

Relapsing, recurrent or repeat peritonitis is a devastating complication for peritoneal dialysis (PD) patients and is usually associated with poor outcomes including prolonged hospitalization, catheter removal, hemodialysis transfer and even death. Despite its critical importance and frequent occurrence, there is limited available evidence to facilitate evidence-informed treatment of PD peritonitis. This editorial comments on the findings and limitations of a randomized controlled study published in this journal, which reported that extending antibiotic treatment duration for an additional week beyond that recommended by the International Society for PD did not reduce the risk of relapsing, recurrent or repeat peritonitis, and may have increased the risk of repeat peritonitis. These results are explored in the context of the existing literature and recommendations for practice and research are provided.

Two decades of analysis of peritonitis in peritoneal dialysis in Andalusia: Epidemiological, clinical, microbiological and progression aspects

BACKGROUND

This study focuses on the main complication associated with peritoneal dialysis, peritonitis. Its relevance derives from its high morbidity, the negative effect it has on the peritoneum as a dialysis membrane and its financial cost.

METHODS

Analytical, non-interventional, observational cohort study, whose main objective is the analysis of peritonitis in patients on peritoneal dialysis in Andalusia from 1 January 1999 to 31 December 2017, with a total of 2,904 peritonitis cases. The database used is the Andalusian Autonomous Transplant Coordination Information System (SICATA).

OBJECTIVES

To ascertain how the rate of peritonitis is evolving in our community, analyse descriptive data pertaining to patients and peritonitis, ascertain the course of these infectious complications and analyse the factors that influence these cases of peritonitis and their outcomes: germ, hospitalisation and date.

RESULTS

The rate of peritonitis decreased progressively during the study period, from 0.7 peritonitis per patient in 1999 to 0.33 at the end of the period. Most infections were treated on an outpatient basis (72.5%). The most common germs were Gram-positive (55.9%), including coagulase-negative staphylococci (28.1%). Most cases of peritonitis progressed to healing (77.8%). The factors that significantly influence the need for hospitalisation and peritonitis progression were the causative germ and associated exit site infection.

CONCLUSIONS

In our population, the rate of peritonitis decreased progressively during the study period, meeting guideline recommendations.

Long-term trends in the incidence of peritoneal dialysis-related peritonitis disclose an increasing relevance of streptococcal infections: A longitudinal study

Background

The selective impact of strategies for prevention of PD-related peritonitis (PDrP) may have modified, in the long term, the causal spectrum, clinical presentation and outcomes of these infections.

Objectives

To compare trends in the incidence of PDrP by different microorganisms during a 30-year period, with a particular focus on streptococcal infections. To analyze the clinical presentation and outcomes of these infections. Secondarily, to investigate how the isolation of different species of streptococci can influence the clinical course of PDrP by this genus of bacteria.

Method

Following a retrospective, observational design we investigated 1061 PDrP (1990–2019). We used joinpoint regression analysis to explore trends in the incidence of PDrP by different microorganisms, and compared the risk profile (Cox), clinical presentation and outcomes (logistic regression) of these infections.

Main results

Our data showed a progressive decline in the incidence of PDrP by staphylococci and Gram negative bacteria, while the absolute rates of streptococcal (average annual percent change +1.6%, 95% CI -0.1/+3.2) and polymicrobial (+1.8%, +0.1/+3.5) infections tended to increase, during the same period. Remarkably, streptococci were isolated in 58.6% of polymicrobial infections, and patients who suffered a streptococcal PDrP had a 35.8% chance of presenting at least one other infection by the same genus. The risk profile for streptococcal infections was comparable to that observed for PDrP overall. Streptococcal PDrP were associated with a severe initial inflammatory response, but their clinical course was generally nonaggressive thereafter. We did not observe a differential effect of different groups of streptococci on the clinical presentation or outcome of PDrP.

Conclusions

Time trends in the incidence of PDrP by different microorganisms have granted streptococci an increasing relevance as causative agents of these infections, during the last three decades. This behaviour suggests that current measures of prevention of PDrP may not be sufficiently effective, in the case of this genus of microorganisms.

Overhydration and low serum prealbumin predict peritoneal dialysis-related peritonitis in continuous ambulatory peritoneal dialysis patients

Background

In this study, we focused on the role of overhydration (OH) and low serum prealbumin concentration in predicting peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients over a 3-year period.

Methods

We measured serum prealbumin concentration and OH by body composition monitor in 278 CAPD patients (159 males and 119 females) with a mean age of 46 years and a median peritoneal dialysis (PD) duration of 21 months. Cases of PD-related peritonitis were collected over 3 years.

Results

After the 3-year follow-up, 44 patients were diagnosed with PD-related peritonitis (15.8%). Low education, serum glucose, prealbumin, and OH were independent risk factors for predicting peritonitis over 36 months in CAPD patients. Based on the ROC curve model and Kaplan-Meier analysis, we realized that low prealbumin and high OH were independent predictors of 3-year peritonitis in CAPD patients (Prealbumin: AUC = 0.838, cut-off value = 32.5 mg/dL, Se = 90.9%, Sp = 32.9%; OH: AUC = 0.851, cut-off value = 1.33 L, Se = 79.5%, Sp = 85.5%; and log-rank test p <  0.001, respectively).

Conclusion

Overhydration and low serum prealbumin were the independent predictors of PD-related peritonitis in CAPD patients.

A bibliometric analysis of the 100 most influential papers on peritoneal dialysis

BACKGROUND

We aimed to identify the 100 most cited articles published on peritoneal dialysis (PD) and analyze their characteristics to provide information on the achievements and developments of PD research over the past decades.

METHODS

The Science Citation Index Expanded (SCIE) in the Web of Science Core Collection was comprehensively searched from 2000 to 2018, using the keywords "Peritoneal dialysis" or "Dialyses, Peritoneal" or "Dialysis, Peritoneal" or "Peritoneal Dialyses". The top 100 cited articles were retrieved by reading titles and abstracts. Significant information was further elicited, including the authors, journals, countries, institutions, and publication year.

RESULTS

The United States was the most productive country (n = 51), Li Pkt published the highest number of papers (n = 7), the Journal of the American Society of Nephrology produced the highest number of contributions (n = 28), and Baxter International Inc., the University of California System, and the University of Toronto were the institutions with the highest number of articles (n = 10).

CONCLUSIONS

This is the first bibliometric study to identify the most influential papers in PD research. This report describes the major changes and advances in research regarding PD as a guide for writing a citable article.

Relationship between initial peritoneal dialysis modality and risk of peritonitis

Peritonitis is a critical complication of peritoneal dialysis (PD). Investigators have reported the risk of peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD) versus automated peritoneal dialysis (APD), but the available evidence is predominantly based on observational studies which failed to report on the connection type. Our understanding of the relationship between peritonitis risk and PD modality thus remained insufficient. We studied 285 participants who began PD treatment between 1997 and 2014 at three hospitals in Nara Prefecture in Japan. We matched 106 APD patients with 106 CAPD patients based on their propensity scores. The primary outcome was time to first episode of peritonitis within 3 years after PD commencement. In total, PD peritonitis occurred in 64 patients during the study period. Patients initiated on APD had a lower risk of peritonitis than did those initiated on CAPD in both the unadjusted and adjusted models. The hazard ratio (HR) and 95% confidence interval (CI) for the primary endpoint were 0.30 (0.17–0.53) in the fully adjusted model including connection type. In the matched cohort, APD patients had a significantly lower risk of peritonitis than did CAPD patients (log-rank: p < 0.001, HR 0.32, 95% CI 0.16–0.59). The weighting-adjusted analysis of the inverse probability of treatment yielded a similar result (HR 0.35, 95% CI 0.18–0.67). In conclusion, patients initiated on APD at PD commencement had a reduced risk of peritonitis compared with those initiated on CAPD, suggesting APD may be preferable for prevention of peritonitis among PD patients.

Comparison of clinical features and outcomes in peritoneal dialysis-associated peritonitis patients with and without diabetes: A multicenter retrospective cohort study

BACKGROUND

The number of end-stage renal disease patients with diabetes mellitus (DM) who are undergoing peritoneal dialysis is increasing. Peritoneal dialysis-associated peritonitis (PDAP) is a serious complication of peritoneal dialysis leading to technical failure and increased mortality in patients undergoing peritoneal dialysis. The profile of clinical symptoms, distribution of pathogenic organisms, and response of PDAP to medical management in the subset of end-stage renal disease patients with DM have not been reported previously. Discrepant results have been found in long-term prognostic outcomes of PDAP in patients with DM. We inferred that DM is associated with bad outcomes in PDAP patients.

AIM

To compare the clinical features and outcomes of PDAP between patients with DM and those without.

METHODS

In this multicenter retrospective cohort study, we enrolled patients who had at least one episode of PDAP during the study period. The patients were followed for a median of 31.1 mo. They were divided into a DM group and a non-DM group. Clinical features, therapeutic outcomes, and long-term prognostic outcomes were compared between the two groups. Risk factors associated with therapeutic outcomes of PDAP were analyzed using multivariable logistic regression. A Cox proportional hazards model was constructed to examine the influence of DM on patient survival and incidence of technical failure.

RESULTS

Overall, 373 episodes occurred in the DM group (n = 214) and 692 episodes occurred in the non-DM group (n = 395). The rates of abdominal pain and fever were similar in the two groups (P > 0.05). The DM group had more infections with coagulase-negative Staphylococcus and less infections with Escherichia coli (E. coli) as compared to the non-DM group (P < 0.05). Multivariate logistic regression analysis revealed no association between the presence of diabetes and rates of complete cure, catheter removal, PDAP-related death, or relapse of PDAP (P > 0.05). Patients in the DM group were older and had a higher burden of cardiovascular disease, with lower level of serum albumin, but a higher estimated glomerular filtration rate (P < 0.05). Cox proportional hazards model confirmed that the presence of diabetes was a significant predictor of all-cause mortality (hazard ratio = 1.531, 95% confidence interval: 1.091-2.148, P < 0.05), but did not predict the occurrence of technical failure (P > 0.05).

CONCLUSION

PDAP patients with diabetes have similar symptomology and are predisposed to coagulase-negative Staphylococcus but not E. coli infection compared those without. Diabetes is associated with higher all-cause mortality but not therapeutic outcomes of PDAP.

Roseomonas species infections in humans: a systematic review

Roseomonas species have been recognized to cause infections in immunocompromised individuals. The purpose of this study was to systemically review all published cases of Roseomonas infections in humans and describe the epidemiology, microbiology, antimicrobial susceptibility, treatment and outcomes of these infections in humans. We performed a systematic review of PubMed (through 20th Octrober 2019) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of Roseomonas species infections. A total of 37 studies, containing data of 99 patients, were included in the analysis. The most common Roseomonas infections were those of the bloodstream in 74.7% (74 patients), musculoskeletal infections in 8.1% (8 patients), skin and soft tissue infections (SSTIs) and peritoneal dialysis-associated peritonitis in 6.1% (6 patients) each. Epidemiology of these infections differed, with bacteremias being more prevalent in patients with malignancy and central venous lines, musculoskeletal infections being more prevalent after orthopedic surgery, and SSTIs occurring without any reported underlying cause. Resistance to beta-lactams was very high with penicillin, piperacillin/tazobactam resistance and cephalosporin resistance at 96.6%, 90.7% and 77.8% respectively, while quinolone resistance was 9.1%. Quinolones, carbapenems and cephalosporins are the most common agents used for treatment, irrespectively of the infection site. Overall mortality was 3% (3 patients), with the mortality attributed to Roseomonas being at 1% (1 patient).

Derivation and validation of a risk score predicting risk of early-onset peritonitis among patients initializing peritoneal dialysis: A cohort study

OBJECTIVES

Early onset peritonitis (EOP) increases the risk of clinical complications in patients initializing peritoneal dialysis (PD). This study aimed to develop and validate a risk prediction model for EOP among patients initializing PD.

METHODS

3772 patients registered with the Henan Peritoneal Dialysis Registry (HPDR) between 2007 and 2015 were included. The main outcome, EOP, was defined as incident peritonitis occurring within 6 months of the initialization of PD. Multivariable logistic regression modeling was applied to derive the risk score. All accessible clinical measurements were screened as potential predictors. Assessment of the developed model in terms of model discrimination and calibration was performed using C statistics and a calibration slope, respectively, and validated internally through a bootstrapping (1000-fold) method to adjust for over-fitting.

RESULTS

The absolute risk of EOP was 14.5%. Age, cardiac function measurements, serum electrolyte test items, lipid profiles, liver function test items, blood urea nitrogen, and white cell count were significant predictors of EOP in the final risk score. Good model discrimination, with C statistics above 0.70, and calibration of agreed observed and predicted risks were identified in the model.

CONCLUSION

A prediction model that quantifies risks of EOP has been developed and validated. It is based on a small number of clinical metabolic measurements that are available for patients initializing PD in many developing countries, and could serve as a tool to screen the population at high risk of EOP.

Seasonality of peritoneal dialysis-related peritonitis in Japan: a single-center, 10-year study

BACKGROUND

Peritonitis is one of the major complications of peritoneal dialysis (PD). Although several reports have indicated seasonality of peritonitis, the observation periods were short, and there were no reports from Japan. Therefore, the purpose of this study was to investigate the long-term seasonality of peritonitis in a single institution in Japan.

METHODS

Of 126 patients who started PD in our hospital between January 1, 2009, and December 31, 2018, 25 patients (15 men, 10 patients with diabetes) developed peritonitis with a total of 42 episodes. The median age at onset was 63 years, and the median duration from the start of PD to the onset of peritonitis was 22 months.

RESULTS

The 10-year incidence of peritonitis was 0.12 episodes per patient-year. Compared with the reference season of winter (December-February), the incidence rate ratios (95% confidence interval) for spring (March-May), summer (June-August), and autumn (September-November) were 1.75 (0.65-4.75), 1.56 (0.57-4.31), and 2.42 (0.94-6.23), respectively. In addition, no seasonality of Gram-positive and Gram-negative organisms was observed.

CONCLUSION

No seasonality was evident in the incidence of PD-related peritonitis in our hospital over a 10-year period. These findings suggest that the development of peritonitis in Japanese PD patients is not affected by seasonality.

Impact of time-varying center volume on technique failure and mortality in peritoneal dialysis

BACKGROUND

Most studies on volume-outcome association used the number of patients at a particular period as the independent variable. However, peritoneal dialysis (PD) is a chronic treatment, and center volume usually changes over a patient's treatment period. Accordingly, this study used the time-varying center volume to explore the volume-outcome association in PD.

METHODS

We conducted a nationwide population-based retrospective cohort study, which included patients who began chronic PD between 2001 and 2010. The risk factors of 5-year technique failure and mortality were analyzed using cause-specific and subdistribution hazard models, respectively. The annual number of patients initiating PD in each patient's treatment center was modeled as a time-varying variable with four categories.

RESULTS

We included 9071 patients who started PD in 100 centers where the number of incident patients ranged from 1 to 107 patients per year (median, 25; interquartile range, 13-42). The estimated 5-year patient and technique survival rates were 64.7% and 66.6%, respectively. Being treated in centers in the largest volume category (the number of incident PD patients ≥43 per year) was associated with significantly lower cause-specific and cumulative hazards for technique failure. No association was found between facility volume and hazards of mortality.

CONCLUSIONS

Receiving PD in high-volume facilities was associated with a lower risk in technique failure. No association was found between facility volume and mortality risk.