Encapsulating peritoneal sclerosis: incidence, predictors, and outcomes. Kidney Int. 2010;77:904-912. [PMID: 20375981 DOI: 10.1038/ki.2010.16]

Role of macrophages in peritoneal dialysis-associated peritoneal fibrosis

Peritoneal dialysis (PD) can be used as renal replacement therapy when chronic kidney disease (CKD) progresses to end-stage renal disease. However, peritoneal fibrosis (PF) is a major cause of PD failure. Studies have demonstrated that PD fluid contains a significantly larger numbers of macrophages compared with the healthy individuals. During PD, macrophages can secrete cytokines to keep peritoneal tissue in sustained low-grade inflammation, and participate in the regulation of fibrosis-related signaling pathways, such as NF-κB, TGF-β/Smad, IL4/STAT6, and PI3K/AKT. A series of basic pathological changes occurs in peritoneal tissues, including epithelial mesenchymal transformation, overgeneration of neovasculature, and abnormal deposition of extracellular matrix. This review focuses on the role of macrophages in promoting PF during PD, summarizes the targets of macrophage-related inhibition of fibrosis, and provides new ideas for clinical research on delaying PF, maintaining the function and integrity of peritoneum, prolonging duration of PD as a renal replacement modality, and achieving longer survival in CKD patients.

Early Diagnosis and Effective Therapy for Encapsulating Peritoneal Sclerosis After Renal Transplantation: A Case Study

Encapsulating peritoneal sclerosis (EPS) is a rare but severe complication of long-term peritoneal dialysis. Characterized by thickening of the peritoneal membrane, EPS leads to bowel encapsulation, ultrafiltration failure, and bowel obstruction. This study describes the case of a 61-year-old man with a history of hypertension and end stage renal disease requiring peritoneal dialysis for ten years who developed EPS after cadaveric renal transplantation. The patient experienced recurrent episodes of abdominal distension, ascites, and ileus starting 10 days after transplantation. Diagnostic imaging and histological examination confirmed EPS, as defined by a podoplanin score of 2 with diffuse accumulation of podoplanin-positive fibroblastic cells in the peritoneal membrane. Early intervention with corticosteroids and tamoxifen led to gradual improvement and stabilization of his condition. This case not only emphasizes the importance of early diagnosis of EPS but also highlights the importance of timely treatment to promote favorable outcomes for patients with this potentially devastating disease.

Pathophysiological Mechanisms of Peritoneal Fibrosis and Peritoneal Membrane Dysfunction in Peritoneal Dialysis

The characteristic feature of chronic peritoneal damage in peritoneal dialysis (PD) is a decline in ultrafiltration capacity associated with pathological fibrosis and angiogenesis. The pathogenesis of peritoneal fibrosis is attributed to bioincompatible factors of PD fluid and peritonitis. Uremia is associated with peritoneal membrane inflammation that affects fibrosis, neoangiogenesis, and baseline peritoneal membrane function. Net ultrafiltration volume is affected by capillary surface area, vasculopathy, peritoneal fibrosis, and lymphangiogenesis. Many inflammatory cytokines induce fibrogenic growth factors, with crosstalk between macrophages and fibroblasts. Transforming growth factor (TGF)-β and vascular endothelial growth factor (VEGF)-A are the key mediators of fibrosis and angiogenesis, respectively. Bioincompatible factors of PD fluid upregulate TGF-β expression by mesothelial cells that contributes to the development of fibrosis. Angiogenesis and lymphangiogenesis can progress during fibrosis via TGF-β-VEGF-A/C pathways. Complement activation occurs in fungal peritonitis and progresses insidiously during PD. Analyses of the human peritoneal membrane have clarified the mechanisms by which encapsulating peritoneal sclerosis develops. Different effects of dialysates on the peritoneal membrane were also recognized, particularly in terms of vascular damage. Understanding the pathophysiologies of the peritoneal membrane will lead to preservation of peritoneal membrane function and improvements in technical survival, mortality, and quality of life for PD patients.

A Case Report and Clinical Insights on Encapsulating Peritoneal Sclerosis: A Rare yet Critical Complication of Peritoneal Dialysis

Peritoneal dialysis (PD) offers a valuable alternative to hemodialysis in the management of end-stage renal disease. While PD offers several advantages, such as improved patient autonomy and preservation of residual kidney functions. It has a wide spectrum of complications, which include mechanical ones such as catheter malfunction or migration, hernias and dialysate leak, or infectious complications, which can be limited to exit site and tunnel infections or extend interiorly to cause peritonitis. One detrimental long-term complication of PD is encapsulating peritoneal sclerosis (EPS), a rare condition characterized by formation of a fibrous cocoon around the bowel loops often initiated by chronic exposure to PD solutions. Other implicated factors include peritonitis, medications and systemic inflammatory conditions. Risk of EPS increases with the duration of PD, particularly after five years. Diagnosis of EPS is challenging and often delayed, given non-specific and wide spectrum of symptoms that may range from loss of appetite to frank signs of abdominal obstruction, which result in significant consequences that can lead to treatment failure and high mortality rate. Imaging in the form of a CT abdomen is the cornerstone in diagnosis, although many patients are diagnosed intraoperatively during exploratory laparotomy. Treatment is usually directed at eliminating provoking factors and directed therapy based on the disease phase.  In this case, we are discussing a 69-year-old patient presenting with signs of abdominal obstruction and found to have a large cystic lesion compressing small bowels. Eventually, patient obstruction was relieved with draining though interventional radiology after a trial of conservative management failed. Our goal is to notify our colleagues that we have a high index of suspicion coupled with prompt imaging evaluation that can facilitate early diagnosis, offering hope for improved patient outcomes through timely management strategies.

Red cell distribution width to albumin ratio predicts treatment failure in peritoneal dialysis-associated peritonitis

BACKGROUND

This study aims to investigate the potential correlation between baseline red cell distribution width (RDW) to albumin ratio (RAR) levels and treatment failure in peritoneal dialysis-associated peritonitis (PDAP) patients.

METHODS

A retrospective single-center study was conducted on 286 PDAP patients. Logistic regression and generalized estimation equation (GEE) analyses were employed to assess the relationship between RAR and treatment failure.

RESULTS

RAR emerged as a robust predictor of treatment failure in PDAP patients. Elevated RAR levels were associated with an increased risk of treatment failure, exhibiting a linear relationship. Even after adjusting for demographic and clinical variables, this association remained statistically significant. ROC analysis revealed that RAR outperformed RDW and albumin individually in predicting PDAP prognosis.

CONCLUSION

This study highlights RAR as a superior prognostic marker for treatment failure in PDAP patients, offering new insights into risk assessment and management strategies for this challenging condition.

Peritoneal Dialysis-Induced Encapsulating Peritonitis: Diagnostic and Therapeutic Challenges in Women with Benign Gynecological Pathology

Background: Peritoneal sclerosis (PS) and its most severe form, encapsulating PS (EPS), are rare entities that can occur in various procedures (liver transplantation, intraperitoneal chemotherapy) or secondary to medications (beta-blockers); however, PS or EPS typically occur in patients undergoing peritoneal dialysis as a form of renal function substitution. Medical or surgical treatments can be applied, but morbidity and mortality have high rates. This condition typically presents clinically as an intestinal obstruction caused by the inclusion of the intestinal loops in the peritoneal fibrous membrane. Methods: Herein, we present data from a single tertiary surgery center that has dedicated teams for patients receiving dialysis. Over 12 years, we analyzed a group of 63 patients admitted for catheter replacement/removal or for acute surgical pathology. In five cases (7.9%), we diagnosed EPS. Two patients with EPS presented with atypical abdominal pathologies requiring emergency surgery: one case of hemoperitoneum caused by a ruptured ovarian cyst and one case of uterine fibroids and metrorrhagia. Results: The definitive diagnoses were established intraoperatively and by analyzing the morpho-pathological changes in the peritoneum. The possible intraoperative challenges included laborious dissection, difficulties in restoring the correct anatomical landmarks, an increased duration of the surgical intervention and a high rate of incidents and accidents. Conclusions: The aim of the present study was to emphasize the possibility of other surgical pathologies overlapping with EPS, increasing the complexity of the surgical intervention.

Renal hyperparathyroidism- a risk factor in the development of encapsulating peritoneal sclerosis

Background

Encapsulating peritoneal sclerosis (EPS) is a rare complication of prolonged peritoneal dialysis (PD) exposure, characterised by peritoneal thickening, calcification, and fibrosis ultimately presenting with life-threatening bowel obstruction. The presence or role of peritoneal calcification in the pathogenesis of EPS is poorly characterised. We hypothesise that significantly aberrant bone mineral metabolism in patients on PD can cause peritoneal calcification which may trigger the development of EPS. We compared the temporal evolution of bone mineral markers during PD in EPS patients with non-EPS long-term PD controls.

Methods

Linear mixed model and logistic regression analysis were used to compare four-monthly serum levels of calcium, phosphate, parathyroid hormone, and alkaline phosphatase (ALP) over the duration of PD exposure in 46 EPS and 46 controls (PD, non-EPS) patients.

Results

EPS patients had higher mean calcium (2.51 vs. 2.41 mmol/L) and ALP (248.00 vs. 111.13 IU/L) levels compared with controls (p=0.01 and p<0.001 respectively, maximum likelihood estimation). Logistic regression analysis demonstrated that high serum calcium and phosphate levels during PD were associated with a 4.5 and 2.9 fold increase in the risk of developing EPS respectively.

Conclusion

High levels of calcium and phosphate in patients on PD were identified to be risk factors for EPS development. Possible reasons for this may be an imbalance of pro-calcifying factors and calcification inhibitors promoting peritoneal calcification which increases peritoneal stiffness. Mechanical alterations may trigger, unregulated fibrosis and subsequent development of EPS. Improved management of secondary hyperparathyroidism during PD may ultimately diminish the EPS risk.

The Intersectoral Coordination Unit for the Sustainable Intensification of Peritoneal Dialysis in Schleswig-Holstein (SKIP-SH) cohort study

BACKGROUND

Peritoneal dialysis (PD) remains underutilised in Germany, prompting the initiation of the Sustainable Intensification of Peritoneal Dialysis in Schleswig-Holstein (SKIP-SH) project. The SKIP-SH cohort study aims to demonstrate the presumed benefits of PD, including enhanced quality of life and reduced healthcare personnel requirements, and to generate data to strengthen the use of PD.

METHODS

The prospective SKIP-SH cohort study recruits patients with advanced chronic kidney disease (CKD) and their caregivers. Comprehensive data, including demographic information, medical history, clinical course, laboratory data, and quality-of-life assessments, are collected. Additionally, biomaterials will be obtained. Primary study objectives are documenting the clinical course and complications, time on therapy for new dialysis patients, reasons influencing treatment modality choices, circumstances at the initiation of dialysis, and quality of life for patients with CKD and their caregivers. The collected biomaterials will serve as a basis for further translational research. Secondary objectives include identifying factors impacting disease-related quality of life, clinical complications, and therapy dropout, estimating ecological footprints, and evaluating healthcare costs and labour time for initiating and sustaining PD treatment.

DISCUSSION

PD is notably underutilised in Germany. The current therapy approach for advanced CKD often lacks emphasis on patient-focused care and quality-of-life considerations. Furthermore, adequate explorative research programs to improve our knowledge of mechanisms leading to disease progression and therapy failure in PD patients are scarce. The overarching goal of the SKIP-SH cohort study is to address the notably low PD prevalence in Germany whilst advocating for a shift towards patient-focused care, quality-of-life considerations, and robust translational research.

TRIAL REGISTRATION

This study was registered with the German trial registry (Deutsches Register klinischer Studien) on November 7, 2023, under trial number DRKS00032983.

Abdominal cocoon: A rare case report of a small bowel obstruction

INTRODUCTION

Sclerosing encapsulating peritonitis (SEP), or abdominal cocoon, is a remarkably rare entity. It consists of a fibrous layer or cocoon-like sac encasing, in most cases, the small bowel. The lack of specific symptoms makes preoperative diagnosis challenging.

CASE PRESENTATION

A 50-year-old patient, with no history of abdominal surgery or medical diseases, was admitted for symptoms of small bowel obstruction. On examination, the patient was underweight with a BMI of 18 kg/m2. Vital signs were stable. His abdomen was mildly distended and soft. Abdominal CT scan showed signs in favor of a left paraduodenal hernia with incarcerated small bowel loops. Intraoperatively, the small bowels were encapsulated in a cocoon-like structure formed by thick fibrous tissue associated with multiple adhesions. Careful adhesiolysis with complete resection of the membrane was performed. The postoperative course was uneventful. One year later, the patient was symptom-free.

DISCUSSION

SEP is thought to be a persistent inflammatory disorder due to a cause that remains unidentified. It is divided into two categories based on its etiology: primary and secondary. The most common mode of SEP revelation is bowel obstruction. Because there is no clear consensus on SEP management, the therapeutic approach typically follows the management strategy of bowel obstruction.

CONCLUSION

SEP is an uncommon cause of bowel obstruction. Preoperative detection can be challenging in the absence of pathognomonic signs. Treatment is based on surgery, specifically entailing complete excision of the cocoon and adhesiolysis.

Dialysis after kidney transplant failure: how to deal with this daunting task?

The best treatment for patients with end-stage kidney disease is kidney transplantation, which, if successful provides both a reduction in mortality and a better quality of life compared to dialysis. Although there has been significant improvement in short-term outcomes after kidney transplantation, long-term graft survival still remains insufficient. As a result, there has been an increase in the number of individuals who need dialysis again after kidney transplant failure, and increasingly contribute to kidney transplant waiting lists. Starting dialysis after graft failure is a difficult task not only for the patients, but also for the nephrologists and the care team. Furthermore, recommendations for management of dialysis after kidney graft loss are lacking. Aim of this narrative review is to provide a perspective on the role of dialysis in the management of patients with failed kidney allograft. Although numerous studies have reported higher mortality in patients undergoing dialysis following kidney allograft failure, reports are contrasting. A patient-centered, individualized approach should drive the choices of initiating dialysis, dialysis modality, maintenance of immunosuppressive drugs and vascular access.

Therapeutic mechanism of baicalein in peritoneal dialysis-associated peritoneal fibrosis based on network pharmacology and experimental validation

Baicalein (5,6,7-trihydroxyflavone) is a traditional Chinese medicine with multiple pharmacological and biological activities including anti-inflammatory and anti-fibrotic effects. However, whether baicalein has a therapeutic impact on peritoneal fibrosis has not been reported yet. In the present study, network pharmacology and molecular docking approaches were performed to evaluate the role and the potential mechanisms of baicalein in attenuating peritoneal dialysis-associated peritoneal fibrosis. The results were validated in both animal models and the cultured human mesothelial cell line. Nine intersection genes among baicalein targets and the human peritoneum RNA-seq dataset including four encapsulating peritoneal sclerosis samples and four controls were predicted by network analysis. Among them, MMP2, BAX, ADORA3, HIF1A, PIM1, CA12, and ALOX5 exhibited higher expression in the peritoneum with encapsulating peritoneal sclerosis compared with those in the control, which might be crucial targets of baicalein against peritoneal fibrosis. Furthermore, KEGG and GO enrichment analyses suggested that baicalein played an anti-peritoneal fibrosis role through the regulating cell proliferation, inflammatory response, and AGE-RAGE signaling pathway. Moreover, molecular docking analysis revealed a strong potential binding between baicalein and MMP2, which was consistent with the predictive results. Importantly, using a mouse model of peritoneal fibrosis by intraperitoneally injecting 4.25% glucose dialysate, we found that baicalein treatment significantly attenuated peritoneal fibrosis, as evident by decreased collagen deposition, protein expression of α-SMA and fibronectin, and peritoneal thickness, at least, by reducing the expression of MMP2, suggesting that baicalein may have therapeutic potential in suppressing peritoneal dialysis-related fibrosis.

Encapsulating peritoneal sclerosis: Your questions answered

Encapsulating peritoneal sclerosis (EPS) is a clinical syndrome hallmarked by the formation of a fibrous cocoon encapsulating the bowel resulting in morbidity and mortality. EPS is most frequently associated with peritoneal dialysis (PD), particularly with its discontinuation. While EPS is one of the most feared complications of PD, the majority of patients receiving PD will not go on to develop EPS. Risk factors for development include time on PD, some types of peritonitis and discontinuation of PD. Owing to its rarity, much of the knowledge of EPS comes from case series and registries and treatments are extrapolated from low-quality evidence. Malnutrition is a significant driver of mortality, and nutritional support is critical in management. We present a case of EPS and frequently asked questions including the definition, diagnosis, epidemiology, pathophysiology, risk factors, role of infection, management and roles of nutrition and surgery.

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.

Development and Validation of a Prediction Model for the Cure of Peritoneal Dialysis-Associated Peritonitis: A Multicenter Observational Study

Aim

Peritoneal dialysis (PD)-associated peritonitis (PDAP) is a severe complication of PD. It is an important issue about whether it can be cured. At present, there is no available prediction model for peritonitis cure. Therefore, this study aimed to develop and validate a prediction model for peritonitis cure in patients with PDAP.

Methods

Patients with PD who developed PDAP from four dialysis centers in Northeast China were followed up. According to the region of PD, data were divided into training and validation datasets. Initially, a nomogram for peritonitis cure was established based on the training dataset. Later, the nomogram performance was assessed by discrimination (C-statistic), calibration, and decision curves.

Results

Totally, 1,011 episodes of peritonitis were included in the final analysis containing 765 in the training dataset and 246 in the validation dataset. During the follow-up period, peritonitis cure was reported in 615 cases from the training dataset and 198 from the validation dataset. Predictors incorporated in the final nomogram included PD duration, serum albumin, antibiotics prior to admission, white cell count in peritoneal dialysate on day 5 (/μl) ≥ 100/μl, and type of causative organisms. The C-statistic values were 0.756 (95% CI: 0.713–0.799) in the training dataset and 0.756 (95% CI: 0.681–0.831) in the validation dataset. The nomogram exhibited favorable performance in terms of calibration in both the training and validation datasets.

Conclusion

This study develops a practical and convenient nomogram for the prediction of peritonitis cure in patients with PDAP, which assists in clinical decision-making.

Risk factors for Encapsulating Peritoneal Sclerosis in patients undergoing peritoneal dialysis: A meta-analysis

Purpose

Encapsulating Peritoneal Sclerosis (EPS) is the most serious complication of long-term peritoneal dialysis (PD), which considerably reduces the patient’s quality of life, leading to patients discontinuing PD. Considering these negative effects, it is necessary to systematically review and determine the risk factors of EPS.

Methods

The PubMed, Embase, Web of Science, Cochrane Library, and China Biology Medicine (CBM) were searched from their inception to January 1st, 2022, and the bibliographies from the citations of relevant articles were manually searched. The ROBINS-I (Risk of Bias in Non-randomized studies of Interventions) tool was used to evaluate the risk of bias of included studies.

Results

Ten studies involving 12595 participants were included in this meta-analysis. The results revealed that a younger age at PD onset (MD = -7.70, 95% CI, -11.53~-3.86), a higher transporter (MD = 0.13, 95% CI, 0.09~0.18), a longer PD duration (SMD = 1.15, 95% CI, 0.68~1.61), a longer peritonitis duration (MD = 12.66, 95% CI, 3.85~21.47), and history of glomerulonephritis (OR = 1.42, 95% CI, 1.02~1.97) were significant risk factors for EPS. However, sex, use of icodextrin, the number of peritonitis episodes, and history of multicystic kidney disease did not affect the risk of EPS.

Conclusions

This review provides a scientific basis for further understanding the etiology of PD-related EPS and improving prevention strategies. More high-quality studies are necessary to validate this paper’s findings.

Encapsulating peritoneal sclerosis: from early diagnosis to successful kidney transplantation

Encapsulating peritoneal sclerosis is an uncommon but serious complication of peritoneal dialysis. In most cases, the symptoms appear after peritoneal dialysis withdrawal, which hampers its diagnosis. We present the case of a 44-years-old Caucasian male who had been on peritoneal dialysis for 6 years and 3 months and was switched to hemodialysis due to ultrafiltration failure. During his last months on peritoneal dialysis, he developed anorexia and asthenia, which were initially attributed to dialysis inadequacy. After hemodialysis induction, the patient developed abdominal pain, increased abdominal volume, obstipation alternating with diarrhea, and weight loss. Computed tomography showed de novo ascites. A diagnosis of early encapsulating peritoneal sclerosis was considered, and treatment was promptly initiated with nutritional support, oral prednisolone, and tamoxifen for one year. The patient progressed with resolution of the symptoms. One month after the end of the treatment, he underwent a successful kidney transplant and remain without any major intercurrences. A high level of clinical suspicion is crucial for the early diagnosis of encapsulating peritoneal sclerosis as the disease can be fatal in advanced stages. This case highlights that with early treatment, kidney transplantation can be successfully performed after an episode of encapsulating peritoneal sclerosis.

Abdominal Cocoon: A Rare Complication of Peritoneal Dialysis in Chronic Kidney Disease

The abdominal cocoon is a rare clinical entity characterized by a thick fibrocollagenous membrane encasing the intestinal loops. Despite its rarity, the abdominal cocoon is one of the most serious complications of peritoneal dialysis. We report the case of a 45-year-old man, with end-stage renal disease on peritoneal dialysis resulting from systemic lupus erythematosus, who presented to the emergency department with progressive abdominal pain for the last two weeks. The pain was associated with nausea, vomiting, abdominal distension, and decreased bowel motion. Upon examination, the vital signs were within the normal limits. Abdominal examination revealed a distended abdomen with generalized tenderness. There was evidence of ascites as indicated by the positive shifting dullness test. The bowel sounds were of increased frequency and intensity. The laboratory findings were non-contributory. The patient underwent an abdominal computed tomography scan that demonstrated a cluster of small intestinal loops in the middle of the abdomen with a surrounding thick and calcified membrane. This made the diagnosis of the abdominal cocoon. The patient underwent an operation to resect the fibrocollagenous membrane. The patient reported improvement after the operation. No recurrence was noted after three months of follow-up. Abdominal cocoon is a very rare complication of peritoneal dialysis. The diagnosis of abdominal cocoon should be kept in mind when the physician encounters a patient with peritoneal dialysis who presented with non-specific and unexplained gastrointestinal symptoms.

Tolerance of peritoneal and residual renal function to intraperitoneal gadolinium-based agents: An animal experimental study of magnetic resonance peritoneography

BACKGROUND

MR (Magnetic resonance) peritoneography is sensible for continuous ambulatory peritoneal dialysis (CAPD)-related complications, which could offer excellent soft-tissue contrast and allows a multiplanar imaging evaluation of complications. However, there is no study about the optimal concentration of the gadolinium-based agents nor the side effects of gadolinium-based agents on peritoneum and residual renal function.

METHOD

Five different groups of uremic rats and two groups of normal rats were injected with a 40-ml mixture of peritoneal dialysate and gadolinium-based agents at varying concentrations prior to MR peritoneography. Thereafter, MR image obtained was evaluated by two experienced radiologists blinded to the concentrations. Peritoneal morphology and thickness of the uremic rats were also assessed using hematoxylin and eosin and Masson staining. Residual renal function was evaluated using serum creatinine levels and hematoxylin and eosin (HE) staining of pathological kidney sections.

RESULTS AND CONCLUSION

The gadolinium-based agents used in this experiment have no significant effect on residual renal function. There is no obvious difference in the image quality at the different gadolinium-based agents concentration. Due to the adverse effects of gadolinium-based agents in the previous studies, we suggest reducing the dose of gadolinium-based agents during MR peritoneography to the lowest limits.

Ongoing Exposure to Peritoneal Dialysis Fluid Alters Resident Peritoneal Macrophage Phenotype and Activation Propensity

Peritoneal dialysis (PD) is a more continuous alternative to haemodialysis, for patients with chronic kidney disease, with considerable initial benefits for survival, patient independence and healthcare costs. However, long-term PD is associated with significant pathology, negating the positive effects over haemodialysis. Importantly, peritonitis and activation of macrophages is closely associated with disease progression and treatment failure. However, recent advances in macrophage biology suggest opposite functions for macrophages of different cellular origins. While monocyte-derived macrophages promote disease progression in some models of fibrosis, tissue resident macrophages have rather been associated with protective roles. Thus, we aimed to identify the relative contribution of tissue resident macrophages to PD induced inflammation in mice. Unexpectedly, we found an incremental loss of homeostatic characteristics, anti-inflammatory and efferocytic functionality in peritoneal resident macrophages, accompanied by enhanced inflammatory responses to external stimuli. Moreover, presence of glucose degradation products within the dialysis fluid led to markedly enhanced inflammation and almost complete disappearance of tissue resident cells. Thus, alterations in tissue resident macrophages may render long-term PD patients sensitive to developing peritonitis and consequently fibrosis/sclerosis.

Neutrophil-to-Lymphocyte Ratio and Treatment Failure in Peritoneal Dialysis-Associated Peritonitis

Objective: We sought to explore if there is an association between neutrophil-to-lymphocyte ratio (NLR) and treatment failure in patients with peritoneal dialysis-associated peritonitis (PDAP).

Methods: Our cohort involved 337 episodes of PDAP experienced by 202 patients who were undergoing continuous ambulatory peritoneal dialysis at a single center from 1 July 2013 to 30 June 2018. The exposures were log-transformed NLR and a categorical variable grouped by the tertiles of NLR levels (T1, <3.75; T2, 3.75–6.53; and T3, >6.53) at baseline. Generalized estimating equation (GEE) and restricted cubic spline (RCS) analyses were done to determine the association between NLR and treatment failure, defined as catheter removal or all-cause mortality during therapy.

Results: After adjusting for other potential predictors, the log-transformed NLR exhibited an incremental relationship with the risk of treatment failure (odds ratio, 1.82; 95% confidence interval, 1.05–3.15). RCS analyses showed that the relationship was positively and linearly correlated (P for nonlinearity = 0.104). As a three-level categorical variable, in reference to T1, the T3 of NLR showed a 3.41-fold increased venture of treatment failure in fully adjusted model. Subgroup analyses suggested that the prognostic relevance of NLR in PDAP was particularly significant in gram-negative peritonitis.

Conclusions: A greater level of NLR at baseline was remarkably associated with a higher incidence of treatment failure among PDAP episodes regardless of other potential risk factors.

Risk factors and clinical outcomes of encapsulating peritoneal sclerosis: A case-control study from China

BACKGROUND

Encapsulating peritoneal sclerosis (EPS) is an uncommon, but serious complication in patients with continuous ambulatory peritoneal dialysis (PD) who have a considerable mortality rate. This study aimed to identify risk factors and outcomes of EPS in Chinese patients on PD.

METHODS

Sixteen patients on PD who met the International Society for Peritoneal Dialysis criteria for diagnosis of EPS in the First Affiliated Hospital of Sun Yat-Sen University from 1997 to 2018 were included. Patients without EPS were matched for age, sex and the duration of PD and selected at a 1:3 ratio for the controls. A case-control study was conducted to analyse the clinical profile and risk factors associated with EPS in patients.

RESULTS

The prevalence of EPS in patients on PD in our centre was 0.55%. The percentage of EPS significantly increased with the duration of PD. In univariate regression analysis, a history of peritonitis (odds ratios (OR): 2.83; 95% confidence interval (CI): 0.82-9.68; p = 0.08), peritoneal glucose exposure (OR: 1.12; 95% CI: 1.03-1.22; p < 0.01) and a high peritoneal transport status (OR: 14.70; 95% CI: 1.85-117.02; p < 0.01) were associated with EPS in patients on PD. However in the multivariate model, only a high peritoneal transport status (adjusted odds ratios (aOR): 13.65; 95% CI: 1.69-109.96; p = 0.01) was independently associated with EPS.

CONCLUSION

The rate of EPS significantly increases with the duration of PD. Progressive peritoneal dysfunction, especially a high peritoneal transport status, is associated with a higher risk of EPS in this population.

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.

Clinical improvement of encapsulating peritoneal sclerosis after challenging course and 6 months of total parenteral nutrition in child with nephronophthisis: a case report

BACKGROUND

Encapsulating peritoneal sclerosis is a rare but potentially lethal complication of long-term peritoneal dialysis that is associated with significant morbidity and mortality. The occurrence of encapsulating peritoneal sclerosis varies worldwide, but is increased in patients maintained on peritoneal dialysis for 5-8 years. The etiology of encapsulating peritoneal sclerosis remains unidentified, and a high index of clinical suspicion is required for diagnosis.

CASE PRESENTATION

We report a 5-year-old Saudi female with end-stage renal disease secondary to nephronophthisis type 2. She underwent peritoneal dialysis for 30 months, with four episodes of peritonitis. She presented with clinical signs of peritonitis. Three days later, she developed septic shock, which required pediatric intensive care unit admission. The peritoneal dialysis catheter was removed because of refractory peritonitis. Her course was complicated by small bowel perforation, and severe adhesions were revealed on abdominal ultrasound and computed tomography, consistent with a diagnosis of EPS. This finding was later confirmed by diagnostic laparotomy performed twice and complicated by recurrent abdominal wall fistula. She received total parenteral nutrition for 6 months and several courses of antibiotics. The patient received supportive treatment including nutritional optimization and treatment for infection. No other treatments, such as immunosuppression, were administered to avoid risk of infection. Following a complicated hospital course, the patient restarted oral intake after 6 months of total parenteral nutrition dependency. Her abdominal fistula resolved completely, and she was maintained on hemodialysis for few years before she received a kidney transplant.

CONCLUSION

When treating patients using peritoneal dialysis, it is important to consider encapsulating peritoneal sclerosis with refractory peritonitis, which is not always easy to identify, particularly if the patient has been maintained on peritoneal dialysis for less than 3 years. Early identification of encapsulating peritoneal sclerosis and appropriate conservative treatment, including nutritional optimization and treatment of infections, are essential to achieve a better prognosis.

Red blood cell distribution width and peritoneal dialysis-associated peritonitis prognosis

Objective

Red blood cell distribution width (RDW) is a parameter of the heterogeneity of circulating erythrocyte size. Recent researches have pointed out a link among RDW, chronic kidney disease, and inflammation. We sought to investigate the prognostic value of baseline RDW in patients with peritoneal dialysis-associated peritonitis (PDAP).

Methods

Our study included 337 peritonitis episodes experienced by 202 patients who were undergoing continuous ambulatory peritoneal dialysis (CAPD) at a single center from 2013 to 2018. Episodes were categorized according to the tertiles of baseline RDW levels (T1, <13.2%; T2, 13.2−14.3%; T3, >14.3%). Routine logistic regression and generalized estimating equation (GEE) were used to estimate the association between RDW and treatment failure, which was defined as relapse/recurrent episodes, catheter removal, or death during therapy.

Results

After adjusting for other potential predictors, RDW exhibited an incremental relationship with the risk of treatment failure. The baseline RDW of T3 indicated a 43% and 52% increased venture of treatment failure in logistic and GEE analyses, respectively, compared with T1. As a continuous variable, the fitting curve based on restricted cubic spiline showed that the relationship was nonlinearly but positively correlated. The multivariate model A (combined RDW with baseline age, albumin, serum ferritin, and duration on CAPD) showed an area under the curve of 0.671 (95% confidence interval, 0.5920.749) for the prediction of treatment failure.

Conclusions

A Higher baseline level of RDW was significantly associated with a greater rate of treatment failure among PDAP episodes independent of other potential predictors.

Encapsulating Peritoneal Sclerosis and Mortality Related to Infection in Patients on Combination Once-Weekly Hemodialysis with Peritoneal Dialysis

INTRODUCTION

Previous studies showed that the combination of peritoneal dialysis (PD) and once-weekly hemodialysis is associated with lower all-cause and cardiovascular mortality. This study aimed to compare the incidence of encapsulating peritoneal sclerosis (EPS) and infection-related mortality among those on combination therapy and those on PD alone.

METHODS

This prospective study on the Japanese Renal Data Registry included patients on PD from 2010 to 2014. Subjects were followed up until the end of 2015. Exposure of interest was combination therapy compared with PD alone. Patients who transitioned to combination therapy were matched with those on PD alone by propensity scores. Outcomes were EPS and infection-related mortality. Data were analyzed using Cox regression models.

RESULTS

Among the matched cohort, 608 and 869 patients were on combination therapy and on PD alone, respectively. Dialysate-to-plasma creatinine (D/P Cr) ratio decreased over time among those on combination therapy, while the ratio increased among those on PD alone (p = 0.01 by the mixed-effects model). During a median follow-up of 2.5 years, 33 experienced EPS and 55 died of infection. Combination therapy was associated with lower infection-related mortality (HR [95% CI]: 0.52 [0.28-0.95]) but not with EPS (HR: 1.21 [0.61-2.40]). Lower mortality was not limited to intra-abdominal infection but also observed for pulmonary infection. Sensitivity analyses considering the effects of dialysis facilities yielded similar results.

CONCLUSIONS

Combination therapy was associated with lower infection-related mortality. It was also associated with a decline in the D/P Cr ratio over time but not with lower incidence of EPS during the short observation period.

Risk factors for peritoneal dialysis withdrawal due to peritoneal dialysis-related peritonitis

BACKGROUND

Peritoneal dialysis has become commonly used for renal replacement therapy; however, some patients withdraw from peritoneal dialysis due to complications, including peritoneal dialysis-related peritonitis, resulting in the low number of patients on peritoneal dialysis. Risk factors for peritoneal dialysis withdrawal due to peritoneal dialysis-related peritonitis are less certain. This retrospective study aimed to investigate these risk factors.

METHODS

We retrospectively analyzed clinical characteristics, laboratory data, and causative microorganisms of 204 episodes of peritoneal dialysis-related peritonitis between 2007 and 2018 at our institution.

RESULTS

Of the 204 episodes, 38 resulted in withdrawal from peritoneal dialysis due to peritoneal dialysis-related peritonitis. The number of peritonitis episodes per patient-year and the incidence of cardiovascular disease were significantly higher in the withdrawal group. Similarly, this group had low levels of serum creatinine, urea nitrogen, serum albumin, alanine aminotransferase, cholinesterase and high C-reactive protein, and second dialysate cell counts after antibiotic administration. Multivariate logistic regression analysis revealed that serum albumin (odds ratio: 0.465; 95% confidence interval: 0.249-0.868; P=0.016) and cardiovascular disease (odds ratio: 2.508; 95% confidence interval: 1.184-5.315; P=0.016) exhibited significant differences.

CONCLUSIONS

The results of this study suggest that hypoalbuminemia and the presence of cardiovascular disease were independent risk factors for withdrawal from peritoneal dialysis due to peritoneal dialysis-related peritonitis.

Encapsulated Peritoneal Sclerosis Masquerading as an Abdominal Catastrophe in Peritoneal Dialysis Therapy

Encapsulated peritoneal sclerosis (EPS) is a rare but known complication of peritoneal dialysis (PD) therapy in patients with end-stage renal disease (ESRD). It commonly manifests insidiously with recurrent intestinal obstruction and malnutrition, worsening over time. We report an ESRD patient on PD therapy for six years presenting with an acute intestinal obstruction, bowel hernia, bowel ischemia, and hemodynamic instability. CT abdomen revealed thickening of walls of colon and ileum in the right lower quadrant, with signs of small bowel obstruction. Patient underwent emergency laparotomy for the repair of hernia and resection of ischemic bowel, and intraoperatively, was found to have dusky, edematous, thickened, inflamed, and distended distal bowels with adhesions in the right lower quadrant. The pathological examination revealed a thin membrane encasing the ileum, colon and the mesenteric tissue diffusely. Microscopic examination of resected bowel showed marked submucosal edema with myxoid and inflammatory changes. Based on these clinical, radiological and pathological findings, a diagnosis of EPS was established. Her postoperative course was complicated by recurrent intraabdominal bleeding with hemoperitoneum, leading to disseminated intravascular coagulation, multiorgan failure, and death, two weeks after the surgery. EPS can present as an acute abdominal catastrophe. Although there are recommendations for ascertainment of EPS diagnosis, there are no clear guidelines for safe and effective surgical strategies and these warrant further research.

A Matrix Metalloproteinase-2-Based Nomogram to Assess the Risk of Encapsulating Peritoneal Sclerosis in Peritoneal Dialysis Patients

Background

Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication of peritoneal dialysis (PD). So far, there is no biomarker-based prediction tool available for EPS. Matrix metalloproteinase-2 (MMP-2) is a protein involved in the breakdown of the extracellular matrix, and the effluent MMP-2 can be a potential biomarker of EPS. This study is aimed at developing a nomogram for EPS based on effluent MMP-2 levels. Patients and Methods. We enrolled 18 EPS patients and 90 gender-matched PD patients without EPS in this cross-sectional case-controlled study. The effluent MMP-2 levels and possible risk factors for EPS were analyzed using multivariable logistic regression, and a nomogram was developed. The nomogram was validated using 200 bootstrap resamples to reduce overfit bias.

Results

The effluent MMP-2 levels in EPS patients were significantly higher than those in normal PD patients (p < 0.001, Manny-Whitney U test). Effluent MMP-2 levels and PD duration were independently associated with EPS risks (p < 0.001 and p = 0.001) in multivariate logistic regression. A nomogram based on MMP-2 levels and PD duration was proposed. The AUC of MMP-2 was 0.824, and the AUC of the nomogram was 0.907 (p = 0.05).

Conclusion

A nomogram based on effluent MMP-2 levels and PD duration may predict EPS with high accuracy.

Treatments and outcomes of encapsulating peritoneal sclerosis in patients undergoing peritoneal dialysis: 295 cases from a nationwide inpatient database in Japan

BACKGROUND

The number of patients undergoing renal replacement therapy is increasing. We evaluated the practice patterns and outcomes of encapsulating peritoneal sclerosis (EPS) in patients undergoing peritoneal dialysis.

METHODS

Using a Japanese national inpatient database, we identified 295 patients with EPS who were hospitalized from July 2010 to March 2017. We categorized them into four groups: those who underwent surgery only (n = 39), those who received corticosteroid treatment only (n = 70), those who underwent both (n = 30), and those who underwent neither (n = 156). We investigated their characteristics, treatments, and outcomes.

RESULTS

More than half of patients were males and never-smokers and had a normal body mass index. Patients tended to undergo parenteral nutrition for 2 months. The proportions of emergency admission, intensive care unit (ICU) admission, central venous catheterization, catecholamine use, mechanical ventilation, and continuous hemodiafiltration were significantly different among the four groups (61%, 8.1%, 37.0%, 44.0%, 8.8%, and 5.8%, respectively). The both-treatment group had a significantly longer hospital stay (37.0 vs. 37.5 vs. 72.5 vs. 31.0 days, p < 0.001) and higher costs (US$16,554 vs. US$17,029 vs. US$33,757 vs. US$13,983, p < 0.001) than the other groups. In total, 52 patients (18%) died during hospitalization. There was no significant difference in inhospital complications and death, discharge status, 30-day readmission, or length of ICU stay among the four groups.

CONCLUSIONS

Our findings provide useful information for clinicians and patients hospitalized for treatment of EPS.

Ten-year survival of patients treated with peritoneal dialysis: A prospective observational cohort study

BACKGROUND

Few studies evaluated over 5-year outcomes of dialysis patients. This study examined 10-year all-cause mortality and death-censored technique failure in a cohort of incident peritoneal dialysis (PD) individuals.

METHODS

Five hundred and thirty-three incident PD individuals from 2006 to 2008 were prospectively followed up for more than 10 years until 2018. Clinical characteristics at PD initiation were collected. The primary outcome was all-cause mortality, and the secondary outcome was death-censored technique failure. Cox hazards models were fit using clinical characteristics at PD initiation.

RESULTS

The mean age starting PD for these participants was 48 ± 16 years; 130 (24%) patients had diabetic nephropathy. During follow-up, 208 patients died, and 84 patients experienced technique failures. The 1, 3, 5, and 10 years' survival rates for incident PD patients were 93%, 81%, 64%, and 36%, respectively, and the technical survival rates were 98%, 93%, 85%, and 62%, respectively. Mortality risk was much higher after 3 years on PD. The peritonitis rate was 0.19 episodes per patient-year, and 7 (1.3%) patients had encapsulating peritoneal sclerosis (EPS) giving an incidence rate of 3.1 of 1000 patient-years. The main causes of death were cardiovascular events (97 of 208, 47%), and technique failure was mainly due to peritonitis (41 of 84, 49%). Older age, higher Charlson comorbidity index, and lower level of education were strongly associated with mortality, and diabetic nephropathy was an independent risk factor for technique failure.

CONCLUSIONS

The 10-year's survival and technique survival rates of incident PD patients were 36% and 62%. Long-term PD can be continued successfully with improved outcomes and low risk for EPS.

Vasculopathy plays an important role during the development and relapse of encapsulating peritoneal sclerosis with conventional peritoneal dialysis solutions

Background

Encapsulating peritoneal sclerosis (EPS) is an uncommon but life-threatening complication of peritoneal dialysis (PD) therapy. The causative factors of EPS remain unclear. Pathological studies of the peritoneum affected by EPS and relationships with clinical factors including PD solutions remain lacking. The objective of this study was to examine peritoneal samples from EPS patients and to identify the associations of peritoneal pathology with different clinical factors.

Methods

Peritoneal specimens were obtained at the time of surgical enterolysis in Tsuchiya General Hospital from 1993 to 2016. A total of 223 PD patients were enrolled and analyzed. Tissues were fixed with formalin and processed with hematoxylin and eosin and Masson’s trichrome staining, as well as immunohistochemical staining for CD31 and CD68.

Results

Evaluations could be made in 174 patients who received surgical enterolysis. Conventional or pH-neutral low-glucose degradation product PD solutions were utilized during PD treatment. The conventional PD solution group showed less angiogenesis (P = 0.013) but more severe vasculopathy, in the form of a lower ratio of luminal diameter to vessel diameter (L/V ratio) (P &lt; 0.001) in association with longer PD treatment. Multivariate Cox proportional hazard models revealed that L/V ratio (per 0.1 increase, hazard ratio = 0.88, 95% confidence interval 0.77–0.99, P = 0.047) was significantly associated with a lower incidence of EPS relapse. In contrast, most of the cases in the pH-neutral solution group showed milder vasculopathy.

Conclusions

The pathology of EPS differed between conventional and pH-neutral solution groups. Vasculopathy was related to the development and relapse of EPS in the conventional solution group.

10-year-long survival in a PD patient with severe calcifying encapsulating peritoneal sclerosis treated with tamoxifen: a case-report

BACKGROUND

Encapsulating-peritoneal-sclerosis (EPS) is a rare, but serious and life-threatening complication of peritoneal dialysis (PD). Treatment of EPS consists of discontinuation of PD and maintenance of nutritional status, whereas the role of corticosteroids, tamoxifen and other immunosuppresive agents is not yet fully elucidated.

CASE-PRESENTATION

We report the case of a 28-year-old patient, who developed a severe form of calcifying EPS after a 6-year-long therapy with automated PD. The clinical presentation was severe with repeated episodes of total bowel obstruction, weight loss and malnutrition that mandated his prolonged hospitalization. Initial treatment included corticosteroids and tamoxifen (20 mg/day) with a clinically meaningful improvement in gastrointestinal function and nutritional status over the first 6-12 months. Corticosteroids were discontinued at 18 months, but owing to persistence of calcifying lesions and peritoneal thickening in repeated computed-tomography (CT) scans, tamoxifen remained unmodified at a low-dose of 20 mg/day for a 10-year-long period. During follow-up, the patient remained symptoms-free in an excellent clinical condition and the CT findings were unchanged.

CONCLUSIONS

Long-term administration of tamoxifen was not accompanied by any drug-related adverse effects and potentially exerted a beneficial action on down-regulation of inflammatory and fibrotic processes and improvement of gastrointestinal function, nutritional status and overall health-related quality of life.

Estimating risk of encapsulating peritoneal sclerosis accounting for the competing risk of death

Background

Risk of encapsulating peritoneal sclerosis (EPS) is strongly associated with the duration of peritoneal dialysis (PD), such that patients who have been on PD for some time may consider elective transfer to haemodialysis to mitigate the risk of EPS. There is a need to determine this risk to better inform clinical decision making, but previous studies have not allowed for the competing risk of death.

Methods

This study included new adult PD patients in Australia and New Zealand (ANZ; 1990–2010) or Scotland (2000–08) followed until 2012. Age, time on PD, primary renal disease, gender, data set and diabetic status were evaluated as predictors at the start of PD, then at 3 and 5 years after starting PD using flexible parametric competing risks models.

Results

In 17 396 patients (16 162 ANZ, 1234 Scotland), EPS was observed in 99 (0.57%) patients, less frequently in ANZ patients (n = 65; 0.4%) than in Scottish patients (n = 34; 2.8%). The estimated risk of EPS was much lower when the competing risk of death was taken into account (1 Kaplan–Meier = 0.0126, cumulative incidence function = 0.0054). Strong predictors of EPS included age, primary renal disease and time on PD. The risk of EPS was reasonably discriminated at the start of PD (C-statistic = 0.74–0.79) and this improved at 3 and 5 years after starting PD (C-statistic = 0.81–0.92).

Conclusions

EPS risk estimates are lower when calculated using competing risk of death analyses. A patient’s estimated risk of EPS is country-specific and can be predicted using age, primary renal disease and duration of PD.

Experimental studies on computed tomographic peritoneography. Peritoneal and residual renal function tolerance to iodinated contrast media injected into the peritoneal cavity

Computed tomographic (CT) peritoneography has been widely used as reference standard to evaluate continuous ambulatory peritoneal dialysis-related complications. However, given the varying CT peritoneography approaches used across different institutions, there is no standard value for non-ionic iodinated contrast media (ICM) concentration. Few studies have currently investigated whether non-ionic iodinated contrast media (non-ionic ICM) affects peritoneal function or residual renal function (RRF). This study aimed to determine whether different non-ionic ICM concentrations affect peritoneum and RRF and attempted to evaluate CT peritoneography images to identify the optimal non-ionic ICM concentrations in animals. To this end, 25 male Sprague-Dawley rats were used to establish uraemic models, after which they were injected with a 40-mL mixture of peritoneal dialysate and iohexol at varying concentrations prior to CT peritoneography. Thereafter, two experienced radiologists blinded to the rat groupings evaluated image quality, peritoneal morphology and thickness were assessed using hematoxylin and eosin and Masson staining, and RRF was evaluated using serum creatinine levels hematoxylin and eosin staining of pathological kidney sections. Briefly, non-ionic ICM had negligible effects on the peritoneum and RRF. Our results suggest that a mixture containing 50 mL (350 mgI/mL) iohexol/2 L peritoneal dialysate can be used as reference in rats.

Long-term outcomes in patients with encapsulating peritoneal sclerosis managed with nutritional support

BACKGROUND

Little is known about long-term survivors with encapsulating peritoneal sclerosis (EPS). Published literature focuses on patients managed surgically. We describe our experience of the long-term outcomes in patients with EPS conservatively managed with nutritional support alone.

METHODS

This is a single-centre retrospective observational study of patients who had survived for ≥5 years since diagnosis. EPS survivors were invited for review of symptoms, nutritional assessment and evaluation of quality of life. Radiological progression was assessed based on serial computed tomography (CT) scores for each patient.

RESULTS

A total of 23 patients with a diagnosis of EPS for at least 5 years were identified, with 18 patients alive at the time of the study. Of these 18 patients, 10 patients transferred to haemodialysis (HD) and 8 patients received kidney transplants. Commonest symptoms were nausea (91%) and vomiting (73%). Mean body mass index for patients was within the ideal and healthy range, with only 11% suffering from continued weight loss. In all, 70% EPS survivors on HD received nutritional support compared to 15% of those with transplants; 17% required ongoing parenteral nutrition. Of the 11 patients with serial CT scans at least 4 years apart, 10 had an increase in radiological score for EPS but with no apparent correlation to clinical outcomes. There were no significant differences in the reported quality of life between EPS survivors on HD and those transplanted, with self-rated health status equivalent to that reported for the general end-stage kidney disease (ESKD) population.

CONCLUSION

Long-term survival following EPS managed conservatively with nutritional support is feasible, with the majority no longer requiring nutritional support and having a quality of life similar to other patients with ESKD.

Outcomes of the surgical management of encapsulating peritoneal sclerosis: A case series from a single center in Korea

Background

Encapsulating peritoneal sclerosis (EPS) is a rare but near-fatal complication of peritoneal dialysis (PD). Despite the high mortality rate of EPS, the surgical treatment strategy of severe EPS is yet to be established.

Methods

We retrospectively analyzed outcomes of patients with EPS who underwent enterolysis for intractable EPS at Seoul National University Hospital between 2001 and 2018. EPS was diagnosed based on the clinical symptoms and radiological findings of abdominal computed tomography (CT). CT scans were scored according to an EPS scoring system that assessed peritoneal thickening and calcification as well as bowel thickening, tethering, loculation, and dilatation.

Results

Thirteen patients (nine males and four females; age, 48 [29–63] years) underwent enterolysis for severe EPS. PD duration (11 [6–21] years) was not associated with survival. Two patients were newly diagnosed with EPS following kidney transplantation. Five patients died of infectious complications immediately after the surgery. Eight patients survived after the first surgery; however, five of them underwent reoperation but died of persistent infection, fistula formation, or adhesive bowel obstruction. Four young (< 60 years) male patients with relatively low CT scan scores (< 13) survived for > 2 years after the first surgery. Median survival duration from EPS diagnosis was 22 (1.3–184) months and that from the first surgery was 9 (0.3–153) months.

Conclusion

The high mortality rate of EPS suggests the importance of appropriate surgical intervention in young symptomatic male EPS patients with relatively low CT scan scores.

Encapsulating Peritoneal Sclerosis: Pathophysiology and Current Treatment Options

Encapsulating peritoneal sclerosis (EPS) is a life-threatening complication of long-term peritoneal dialysis (PD), which may even occur after patients have switched to hemodialysis (HD) or undergone kidney transplantation. The incidence of EPS varies across the globe and increases with PD vintage. Causative factors are the chronic exposure to bioincompatible PD solutions, which cause long-term modifications of the peritoneum, a high peritoneal transporter status involving high glucose concentrations, peritonitis episodes, and smoldering peritoneal inflammation. Additional potential causes are predisposing genetic factors and some medications. Clinical symptoms comprise signs of intestinal obstruction and a high peritoneal transporter status with incipient ultrafiltration failure. In radiological, macro-, and microscopic studies, a massively fibrotic and calcified peritoneum enclosed the intestine and parietal wall in such cases. Empirical treatments commonly used are corticosteroids and tamoxifen, which has fibrinolytic properties. Immunosuppressants like azathioprine, mycophenolate mofetil, or mTOR inhibitors may also help with reducing inflammation, fibrin deposition, and collagen synthesis and maturation. In animal studies, N-acetylcysteine, colchicine, rosiglitazone, thalidomide, and renin-angiotensin system (RAS) inhibitors yielded promising results. Surgical treatment has mainly been performed in severe cases of intestinal obstruction, with varying results. Mortality rates are still 25–55% in adults and about 14% in children. To reduce the incidence of EPS and improve the outcome of this devastating complication of chronic PD, vigorous consideration of the risk factors, early diagnosis, and timely discontinuation of PD and therapeutic interventions are mandatory, even though these are merely based on empirical evidence.

Cocoon abdomen after chronic peritoneal dialysis

A 66-year-old man presented with nausea, vomiting, and ascites. At laparotomy, an extensive fibrosis of the peritoneum was found to encase the bowel in a cocoon-like fashion. A meticulous dissection was undertaken to strip this encapsulating membrane from the bowel. Histologic study of the excised tissue disclosed extensive hyalinized fibroconnective tissue.

Simultaneous Removal And Reinsertion of the PD Catheter in Relapsing Peritonitis

Background:Relapsing peritonitis in peritoneal dialysis (PD) is associated with lower cure rates and more hemodialysis (HD) transfers, as catheter removal is recommended in these situations. The aim of our study was to evaluate the continuation of PD without perioperative transfer to HD in patients who underwent a simultaneous catheter removal and replacement for relapsing peritonitis.Methods:This was a retrospective monocentric study. Patients with simultaneous catheter removal and replacement for relapsing peritonitis or peritonitis at high risk of relapse (fungal or Pseudomonas infection) between 1 January 2007 and 31 December 2016 were included. The events of interest were the continuation of PD without perioperative transfer to HD, postoperative complications, new infection with the same organism, and technique survival.Results:Of the 271 incident patients in PD during this period, 11 had a simultaneous catheter removal and replacement for relapsing peritonitis (8) or high risk of relapse peritonitis (3). Eight (72.7%) patients pursued PD without transfer to HD. Six infections were due to microorganisms other than gram-positive cocci. At 1 year, 7 (63.6%) of the 11 patients were still on PD. After the surgery, there were no peritonitis or catheter-related infections caused by the same organism.Conclusion:Simultaneous catheter removal and replacement for peritonitis appears to be an effective procedure for maintaining patients on PD.

Surgical Treatment for Encapsulating Peritoneal Sclerosis: 24 Years’ Experience

Background

Encapsulating peritoneal sclerosis (EPS) is a serious complication of long-term peritoneal dialysis. The mortality rate for EPS is high, primarily due to complications related to bowel obstruction. Surgery was previously contraindicated; however, surgical enterolysis is performed for patients in whom bowel obstruction fails to improve.

Methods

This was a retrospective observational study of patients with EPS who received surgical intervention at a single center between November 1993 and October 2017. The severity of intestine damage was characterized by grade-3 peritoneal calcification on abdominal computed tomography (CT) scan and degeneration of the small intestinal wall in surgery.

Results

Two-hundred and forty-three patients with EPS opted for surgery. Among them, 58 had recurrence and required re-surgery; a total of 318 EPS surgeries were performed. Death was related to EPS in 61 patients (25.1%), of whom 15 died postoperatively. Sixty-seven patients (27.6%) died from other causes. The actuarial survival rates at 1, 2, 3, 5, and 8 years after EPS diagnosis were 91%, 83%, 77%, 66%, and 53% respectively. The 50% actuarial survival points after EPS diagnosis and surgery were 104 months and 85 months, respectively. Peritoneal calcification and small intestinal wall degeneration grading showed significant association with the mortality curve for EPS-related death.

Conclusion

Excellent outcomes for EPS are achieved with surgery. The degree of peritoneal deterioration affected the clinical outcomes. Currently, EPS is no longer recognized as a fatal complication.

Encapsulating Peritoneal Sclerosis in Long-Termed Peritoneal Dialysis Patients

Background

Encapsulating peritoneal sclerosis (EPS) is a rare but serious clinical complication of long-term peritoneal dialysis (PD) patients with high mortality. The purpose of this study was to assess the clinical characteristics of patients with EPS and to search for possible factors useful for EPS prevention and early diagnosis.

Method

This retrospective study was performed in a single dialysis center in Taiwan between August 1990 and April 2014. Overall, a total of 565 patients were included and the medical records of those patients who had developed EPS (EPS group) and those who had not developed EPS (control group) were collected. We compared several factors between these two groups.

Result

In the univariate analysis, EPS was significantly associated with a change of transport state (Delta 2) (p = 0.007), duration of PD (p < 0.001), duration of peritonitis treatment (p = 0.001), number of peritonitis episodes (p = 0.002), and fungus related peritonitis (p = 0.031). After multivariate logistic model analysis, we found that only the duration of PD was independently significantly associated with EPS (p = 0.034). In addition, we used the ROC curve and found that a duration of peritoneal dialysis of about 8.4 years is the best cut-off point to predict EPS occurrence.

Conclusion

In this study, long-termed PD duration is the only strong independent risk factor for EPS development. Total peritonitis times, total peritonitis treatment duration, and marked increased peritoneal D/P_cr ratio were also significantly associated with the duration of PD.

Biocompatible dialysis fluids for peritoneal dialysis

BACKGROUND

Biocompatible peritoneal dialysis (PD) solutions, including neutral pH, low glucose degradation product (GDP) solutions and icodextrin, have previously been shown to favourably influence some patient-level outcomes, albeit based on generally sub-optimal quality studies. Several additional randomised controlled trials (RCT) evaluating biocompatible solutions in PD patients have been published recently. This is an update of a review first published in 2014.

OBJECTIVES

This review aimed to look at the benefits and harms of biocompatible PD solutions in comparison to standard PD solutions in patients receiving PD.

SEARCH METHODS

The Cochrane Kidney and Transplant Specialised Register was searched up to 12 February 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All RCTs and quasi-RCTs in adults and children comparing the effects of biocompatible PD solutions (neutral pH, lactate-buffered, low GDP; neutral pH, bicarbonate(± lactate)-buffered, low GDP; glucose polymer (icodextrin)) in PD were included. Studies of amino acid-based solutions were excluded.

DATA COLLECTION AND ANALYSIS

Two authors extracted data on study quality and outcomes. Summary effect estimates were obtained using a random-effects model, and results were expressed as risk ratios and 95% confidence intervals (CI) for categorical variables, and mean differences (MD) or standardised mean differences (SMD) and 95% CI for continuous variables.

MAIN RESULTS

This review update included 42 eligible studies (3262 participants), including six new studies (543 participants). Overall, 29 studies (1971 participants) compared neutral pH, low GDP PD solution with conventional PD solution, and 13 studies (1291 participants) compared icodextrin with conventional PD solution. Risk of bias was assessed as high for sequence generation in three studies, allocation concealment in three studies, attrition bias in 21 studies, and selective outcome reporting bias in 16 studies.Neutral pH, low GDP versus conventional glucose PD solutionUse of neutral pH, low GDP PD solutions improved residual renal function (RRF) preservation (15 studies, 835 participants: SMD 0.19, 95% CI 0.05 to 0.33; high certainty evidence). This approximated to a mean difference in glomerular filtration rate of 0.54 mL/min/1.73 m2 (95% CI 0.14 to 0.93). Better preservation of RRF was evident at all follow-up durations with progressively greater preservation observed with increasing follow up duration. Neutral pH, low GDP PD solution use also improved residual urine volume preservation (11 studies, 791 participants: MD 114.37 mL/day, 95% CI 47.09 to 181.65; high certainty evidence). In low certainty evidence, neutral pH, low GDP solutions may make little or no difference to 4-hour peritoneal ultrafiltration (9 studies, 414 participants: SMD -0.42, 95% CI -0.74 to -0.10) which approximated to a mean difference in peritoneal ultrafiltration of 69.72 mL (16.60 to 122.00 mL) lower, and may increase dialysate:plasma creatinine ratio (10 studies, 746 participants: MD 0.01, 95% CI 0.00 to 0.03), technique failure or death compared with conventional PD solutions. It is uncertain whether neutral pH, low GDP PD solution use led to any differences in peritonitis occurrence, hospitalisation, adverse events (6 studies, 519 participants) or inflow pain (1 study, 58 participants: RR 0.51, 95% CI 0.24 to 1.08).Glucose polymer (icodextrin) versus conventional glucose PD solutionIn moderate certainty evidence, icodextrin probably reduced episodes of uncontrolled fluid overload (2 studies, 100 participants: RR 0.30, 95% CI 0.15 to 0.59) and augmented peritoneal ultrafiltration (4 studies, 102 participants: MD 448.54 mL/d, 95% CI 289.28 to 607.80) without compromising RRF (4 studies, 114 participants: SMD 0.12, 95% CI -0.26 to 0.49; low certainty evidence) which approximated to a mean creatinine clearance of 0.30 mL/min/1.73m2 higher (0.65 lower to 1.23 higher) or urine output (3 studies, 69 participants: MD -88.88 mL/d, 95% CI -356.88 to 179.12; low certainty evidence). It is uncertain whether icodextrin use led to any differences in adverse events (5 studies, 816 participants) technique failure or death.

AUTHORS' CONCLUSIONS

This updated review strengthens evidence that neutral pH, low GDP PD solution improves RRF and urine volume preservation with high certainty. These effects may be related to increased peritoneal solute transport and reduced peritoneal ultrafiltration, although the evidence for these outcomes is of low certainty due to significant heterogeneity and suboptimal methodological quality. Icodextrin prescription increased peritoneal ultrafiltration and mitigated uncontrolled fluid overload with moderate certainty. The effects of either neutral pH, low GDP solution or icodextrin on peritonitis, technique survival and patient survival remain uncertain and require further high quality, adequately powered RCTs.

Should End-of-Life Preferences Be Discussed Routinely before High-Risk Surgery?

Encapsulating peritoneal sclerosis (EPS) is a rare but devastating complication of peritoneal dialysis. It is characterized by peritoneal neovascularization, fibrosis, and calcification ultimately leading to intestinal obstruction and eventual failure. Surgery for EPS has a mortality approaching 50% and most patients require some form of postoperative life-sustaining therapy (LST) during their admission. A 43-year-old gentleman with progressive EPS and significant comorbidities was assessed for enterolysis after a failed first attempt at another center. Because of his comorbidities, postoperative mortality was quoted above 50%. The patient favored surgery to improve his survival and quality of life, but was reluctant to receive prolonged LST in the event of failure of surgical therapy. The surgical team, in conjunction with a palliative care physician, therefore held extensive discussions with the patient and his partner regarding LST and its limitations. Clinical parameters to trigger a transition to palliative care were identified and agreed. Limitations on LST that are directly expressed by patients can represent a contraindication to surgery for many surgeons. Surgical Buy-In is a concept described as a perceived contract, or covenant, between the patient and clinician regarding implied consent for postoperative LST. Currently, preoperative discussions regarding limitations of LST are infrequent, and there can be reticence among patients and surgeons to have these conversations, leading to dissatisfaction on behalf of the patient and their family. After the Montgomery legal ruling, the provision and perception of informed consent are particularly pertinent. The palliative care physician is uniquely placed to contribute to such discussions as part of the surgical multidisciplinary team.

A Clinical Risk Prediction Tool for Peritonitis-Associated Treatment Failure in Peritoneal Dialysis Patients

A tool to predict peritonitis-associated treatment failure among peritoneal dialysis (PD) patients has not yet been established. We conducted a multicentre, retrospective cohort study among 1,025 PD patients between 2006 and 2016 in Thailand to develop and internally validate such a tool. Treatment failure was defined as either a requirement for catheter removal, a switch to haemodialysis, or peritonitis-associated mortality. Prediction model performances were analysed using discrimination (C-statistics) and calibration (Hosmer-Lemeshow test) tests. Predictors were weighted to calculate a risk score. In total, 435 patients with 855 episodes of peritonitis were identified; 215 (25.2%) episodes resulted in treatment failure. A total risk score of 11.5 was developed including, diabetes, systolic blood pressure <90 mmHg, and dialysate leukocyte count >1,000/mm³ and >100/mm³ on days 3-4 and day 5, respectively. The discrimination (C-statistic = 0.92; 95%CI, 0.89-0.94) and calibration (P > 0.05) indicated an excellent performance. No significant difference was observed in the internal validation cohort. The rate of treatment failure in the different groups was 3.0% (low-risk, <1.5 points), 54.4% (moderate-risk, 1.5-9 points), and 89.5% (high-risk, >9 points). A simplified risk-scoring scheme to predict treatment failure may be useful for clinical decision making regarding PD patients with peritonitis. External validation studies are needed.

Encapsulating peritoneal sclerosis

Encapsulating peritoneal sclerosis (EPS) is a debilitating condition characterized by a fibrocollagenous membrane encasing the small intestine, resulting in recurrent small bowel obstructions. EPS is most commonly associated with long-term peritoneal dialysis, though medications, peritoneal infection, and systemic inflammatory disorders have been implicated. Many cases remain idiopathic. Diagnosis is often delayed given the rarity of the disorder combined with non-specific symptoms and laboratory findings. Although cross-sectional imaging with computed tomography of the abdomen can be suggestive of the disorder, many patients undergo exploratory laparotomy for diagnosis. Mortality approaches 50% one year after diagnosis. Treatment for EPS involves treating the underlying condition or eliminating possible inciting agents (i.e. peritoneal dialysis, medications, infections) and nutritional support, frequently with total parenteral nutrition. EPS-specific treatment depends on the disease stage. In the inflammatory stage, corticosteroids are the treatment of choice, while in the fibrotic stage, tamoxifen may be beneficial. In practice, distinguishing between stages may be difficult and both may be used. Surgical intervention, consisting of peritonectomy and enterolysis, is time-consuming and high-risk and is reserved for situations in which conservative medical therapy fails in institutions with surgical expertise in this area. Herein we review the available literature of the etiology, pathogenesis, diagnosis, and treatment of this rare, but potentially devastating disease.