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.

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.

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.

Clinical risk factors and outcomes of massive ascites accumulation after discontinuation of peritoneal dialysis.

Background: Encapsulating peritoneal sclerosis (EPS) is a serious complication of peritoneal dialysis (PD), with high morbidity and mortality that requires an early diagnosis for effective treatment. PD withdrawal and bacterial peritonitis are important triggers for the onset of EPS. However, few studies have focused on cases of PD withdrawal without a clinical diagnosis of peritonitis, cirrhosis, or carcinomatosis. We aimed to compare the clinical characteristics and computed tomography (CT) images of patients with or without ascites in such situations and assess clinical outcomes in terms of mortality.Methods: Our retrospective review included 78 patients who withdraw PD between January 2000 and December 2017.Results: Ten patients had ascites, and 68 did not have a significant intra-abdominal collection. The ascites group had a significantly longer PD duration (months; 134.41 [range, 35.43-181.80] vs. 32.42 [733-183.47], p < 0.001) and higher peritoneal membrane transport status based on the dialysate-to-plasma ratios of creatinine (0.78 ± 0.08 vs. 0.68 ± 0.11, p = 0.009) and glucose (0.27 ± 0.07 vs. 0.636 ± 0.08, p = 0.001) than the control group. CT parameters, including peritoneal calcification, thickness, bowel tethering, or bowel dilatation, were not all present in each patient with ascites and EPS. During the 12-month study period, the ascites group had a higher risk for developing EPS (70% vs. 0%, p < 0.001) and a higher 12-month all-cause mortality (30% vs. 0%, p = 0.002).Conclusions: Ascites accumulation was not rare after PD discontinuation. A longer PD duration and high peritoneal membrane transport status could predict subsequent ascites accumulation. Furthermore, patients with ascites were at a higher risk of EPS.

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.

Encapsulated peritoneal sclerosis: a single center, retrospective analysis of clinical manifestations, risk factors and prognosis.

BACKGROUND: Encapsulated peritoneal sclerosis (EPS) is a multifactorial chronic intra-abdominal inflammatory disorder affecting the peritoneum diffusely. The aim of this study was to evaluate the rates of EPS in our peritoneal dialysis (PD) population, to perform a general assessment of the clinical presentation and to determine the outcome of affected patients and risk factors. METHODS: The medical records of consecutive 384 patients who started PD therapy between January 2001 and November 2016 were evaluated. Socio-demographic characteristics, comorbidities, PD therapy details and infectious complications were recorded. Medical records were examined to make sure that the cases met the ISPD criteria for EPS diagnosis including clinical features and either radiological and/or histopathological confirmation. Patients diagnosed with EPS were identified, and the incidence, clinical presentation, treatments and recent status of the patients were reviewed. Factors that might be associated with EPS formation and mortality were investigated. RESULTS: Two hundred one of 384 patients were female, mean age was 45.9±15.6 years and mean PD follow up time were 42.6±35 months. EPS was developed in 26 patients and EPS development rate was 6.7%. PD follow-up period and duration of hypertonic solution usage were longer in patients with EPS (P<0.001 and P=0.017 respectively). Patients with and without EPS were similar in terms of modality (P=0.21) but treatment duration with APD modality was longer in patients with EPS (P<0.001). The PD follow-up period was found to be a predictor of EPS formation (P<0.001, RR:1.034 [95% CI: 1.020-1.047]). Age (P<0.001, RR:1.039 (95% CI: 1.024-1.053) and use of hypertonic dialysis solution (P=0.007, RR:0.979 (95% CI: 0.965-0.994)) were the factors affecting survival in EPS patients. CONCLUSIONS: EPS is a relatively rare but fatal complication of peritoneal dialysis and extension of PD duration is a risk for EPS formation. Younger age and usage of hypertonic dialysis solution affects mortality in patients with EPS.

Incidence and outcomes of encapsulating peritoneal sclerosis (EPS) and factors associated with severe EPS.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication of long-term peritoneal dialysis (PD). However, previous studies reported large variations in its mortality rates that may associate with a different degree of EPS severity. This study reports the incidence and outcomes of EPS and identifies the risk factors associated with severe EPS. METHODS: We retrospectively analyzed clinical data of EPS patients from 3 medical centers in Taiwan from January 1982 to September 2015, and classified patients as having mild/moderate or severe EPS. Patients with intractable intestinal obstruction/gut-related sepsis that needed surgical intervention or resulted in mortality were in severe EPS group. Follow-up for outcome was through December 31, 2015. Clinical characteristics, peritoneal dialysis (PD)-related parameters, biochemical and imaging results were analyzed and compared between groups. RESULTS: Fifty-eight of 3202 patients undergoing PD during the study period had EPS (prevalence 1.8%). The incidence of EPS increased for patients on PD for >6-8 years (≤6 yrs. vs. >6-8 yrs., 0.0% vs. 1.8%, p = 0.001). Relative to those on PD for >6-8 years, the risk of EPS significantly increased with PD duration longer than 10 years (>10-12 years vs. >6-8 years: OR: 5.5, 95% CI: 1.7-17.1, p < 0.01). Twenty-three patients fulfilled the criteria for severe EPS. The overall mortality rate of EPS was 35% (20/58), and was 74% (17/23) in the severe EPS group. The average serum levels of C-reactive protein (CRP) and intact-parathyroid hormone (i-PTH), which were checked every 3~6 months within one year before diagnosis of EPS, were higher in severe EPS group than in mild/moderate group (p = 0.02, p = 0.08, respectively). Multivariate analysis revealed severe EPS was independently associated with bowel tethering (based on CT), presentation with bloody ascites, diagnosis of EPS after withdrawal from PD, and i-PTH ≥ 384 pg/mL. Receiver operating characteristic analysis indicated that presentation with 2 or more of the 5 risk factors (EPS diagnosis after PD withdrawal, bloody ascites, bowel tethering, CRP ≥ 29 mg/L, and i-PTH ≥ 384 pg/mL) had a good accuracy (AUC = 0.80, p = 0.001) for prediction of severe EPS. CONCLUSIONS: The incidence of EPS increases with PD duration. Severe EPS has high mortality rate and is associated with bowel tethering, presentation of bloody ascites, diagnosis after PD withdrawal, and higher serum levels of i-PTH before EPS diagnosis. Having 2 or more of the 5 risk factors can provide a good accuracy for prediction of severe EPS.

The peritoneal sieving of sodium: a simple and powerful test to rule out the onset of encapsulating peritoneal sclerosis in patients undergoing peritoneal dialysis.

BACKGROUND AND AIMS: Encapsulating peritoneal sclerosis (EPS) is an uncommon but severe complication of peritoneal dialysis (PD). A reliable screening tool to identify patients at risk of developing or not EPS is currently not available. We aimed to evaluate whether the reduction in dialysate sodium concentration (sodium sieving) at 60 min (ΔDNa60), during a peritoneal equilibration test with 3.86% glucose concentration (3.86%-PET) was able to early rule out patients who will not develop EPS. METHODS: Prospective controlled longitudinal (20-year) cohort study. All eligible incident PD patients attending the hospital underwent a 3.86%-PET during the first 3 months following start of PD and then once a year. The dip in ΔDNa60 and other factors were correlated with eventual EPS onset. RESULTS: Of 161 incident PD patients, with a median PD duration of 37.8 (24.7-58.3) months and 64.1 (34.5-108.3) months of follow-up, 13 patients (8%) developed EPS at a median PD duration of 72.7 (56.6-109.4) months and 105.0 (76.4-143.2) months of follow-up. ΔDNa60 demonstrated the best sensitivity and specificity values, estimated by conventional receiver operating characteristic (ROC) curve analysis with an area under the curve (AUC) of 0.90, 0.83 and 0.85 at 1, 2 and 3 years before the onset of EPS, respectively. Multifactorial analysis showed that the most useful factors for predicting EPS were age at start of PD, duration of PD, small solutes transport (D/PCreat) and ΔDNa60; the AUC at 1, 2 and 3 years before the onset of EPS was, respectively, 0.97, 0.96 and 0.94, the positive predictive value being 0.48, 0.57 and 0.42, and the negative predictive value 1.0, 1.0 and 1.0. CONCLUSIONS: It is possible to predict the occurrence and, better, the non-occurrence of EPS using simple parameters such as age at PD start, duration of PD, and parameters obtained by 3.86%-PET such as D/PCreat and ΔDNa60.

Absence of Post-Transplantation Encapsulating Peritoneal Sclerosis after Relatively Short Exposure to Peritoneal Dialysis: Prospective Analysis Using Repeated Abdominal CT Scanning.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is the most severe complication of peritoneal dialysis (PD). Several retrospective reports published between 2007 and 2009 have suggested an increasing incidence of EPS occurring after kidney transplantation. We conducted a prospective observational study to determine the incidence of post-transplantation EPS and identify possible risk factors. METHODS: Consecutive PD patients undergoing kidney transplantation between 2009 and 2013 were included. Encapsulating peritoneal sclerosis was defined as gastrointestinal obstruction combined with radiological evidence of EPS. Gastrointestinal symptoms were assessed using a self-administered Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. Abdominal computed tomography (CT) was performed prospectively at 6 and 18 months post-transplantation. The primary end point was EPS during follow-up. RESULTS: Fifty-three PD patients were included (age 51 ± 14 years). Mean PD duration was 31.3 months. Peritoneal dialysis solutions low in glucose degradation products and icodextrin were used by 86.8% of patients. A fast or average-fast transport status was documented in 83.0%. After a median follow-up of 19 months, complete data of 47 patients were available for analysis. None of the patients developed clinical or radiological signs of EPS. The GSRS score improved from 1.87 to 1.55 (p = 0.024) and body weight increased from 75.9 to 78.3 kg (p = 0.003). Only 1 patient had new onset localized (< 20%) peritoneal thickening on CT 22 months post-transplantation. CONCLUSION: Post-transplantation EPS did not develop in this cohort of patients with a relatively short time of PD exposure. This suggests that these patients can be transplanted safely without concern for the development of EPS, at least within the follow-up period of 19 months.

Significant Decreasing Incidence of Encapsulating Peritoneal Sclerosis in the Dutch Population of Peritoneal Dialysis Patients.

The Dutch Encapsulating Peritoneal Sclerosis (EPS) Registry was started in 2009. Cases were identified by contacting all Dutch nephrologists twice yearly. The predefined criteria for EPS allowed for inclusion of patients with diagnosed and suspected EPS. Cases registered between January 2009 and January 2015 were analyzed with follow-up until September 2015. Fifty-three EPS cases were identified, of which 28.3% were post-transplantation EPS cases. Fourteen patients were initially categorized as suspected EPS, of whom 13 developed EPS. A remarkable 6-fold decrease in the yearly incidence of EPS was observed, from 0.85% in 2009 to 0.14% in 2014. This decrease could not be explained by a decrease in the number of PD patients or average duration of PD treatment in this period. Two-year survival of EPS patients was 52%. The use of tamoxifen and surgical interventions increased significantly over the years. Tamoxifen-treated cases showed a trend to better patient survival and post-transplantation EPS had a significantly favorable outcome. In conclusion, the incidence of EPS has declined significantly in the Netherlands from 2009 to 2014.

Risk factors of severe peritoneal sclerosis in chronic peritoneal dialysis patients.

Peritoneal dialysis (PD) offers the healthiest way for starting renal replacement therapy (RRT) in End Stage Renal Disease patients, however exposes long-term PD patients to a dangerous complication named encapsulating peritoneal sclerosis (EPS). In this study, we searched for possible risk factors of EPS. Data were collected from two PD centers covering period 1995-2012 and comprised 464 patients. Control group defined as PD patients stayed on PD >42 month (n = 122), and case group was 12 confirmed EPS patients. Associations were analyzed using linear regression analysis. Prevalence and incidence of EPS were 2.59% and 8.9% with an incidence of 0.7% patient-years, respectively. The age at start of PD in EPS patients (32.75 ± 10.8 year) was significantly lower compared with control group (49.61 ± 16.18 year, p = .0001). The mean duration of PD in EPS and control group were 2494.4 ± 940.9 and 1890.2 ± 598.8 days (p = .002). Control group had 145 episodes of peritonitis during total duration of 7686 patient months (peritonitis rate of 1/53). This was 1/26 with a total 38 episodes of peritonitis during the total duration of 997 patient months (p = .01) for EPS group. In regression analysis, PD duration, age at PD start and duration of Ultrafiltration failure (UFF) were associated with EPS. Longer time being on PD, younger age, and higher UFF duration were the risk factors for EPS development.

Peritoneal inflammation precedes encapsulating peritoneal sclerosis: results from the GLOBAL Fluid Study.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is an uncommon condition, strongly associated with a long duration of peritoneal dialysis (PD), which is itself associated with increased fibrosis in the peritoneal membrane. The peritoneal membrane is inflamed during PD and inflammation is often associated with fibrosis. We hypothesized that patients who subsequently develop EPS might have a more inflamed peritoneal membrane during PD. METHODS: We performed a nested, case-control study identifying all EPS cases in the UK arm of the GLOBAL Fluid Study and matching them by centre and duration of PD with two to three controls. Dialysate and plasma samples were taken during repeated peritoneal equilibration tests prior to cessation of PD from cases and controls. Samples were assayed by electrochemiluminescence immunoassay for interleukin-1ß (IL-1ß), tumour necrosis factor α (TNF-α), interferon-γ (IFN-γ) and IL-6. Results were analysed by linear mixed models adjusted for age and time on PD. RESULTS: Eleven EPS cases were matched with 26 controls. Dialysate TNF-α {0.64 [95% confidence interval (CI) 0.23, 1.05]} and IL-6 [0.79 (95% CI 0.03, 1.56)] were significantly higher in EPS cases, while IL-1ß [1.06 (95% CI -0.11, 2.23)] and IFN-γ [0.62 (95% CI -0.06, 1.29)] showed a similar trend. Only IL-6 was significantly higher in the plasma [0.42 (95% CI 0.07, 0.78)]. Solute transport was not significantly different between cases and controls but did increase in both groups with the duration of PD. CONCLUSIONS: The peritoneal cavity has higher levels of inflammatory cytokines during PD in patients who subsequently develop EPS, but neither inflammatory cytokines nor peritoneal solute transport clearly discriminates EPS cases. Increased systemic inflammation is also evident and is probably driven by increased peritoneal inflammation.

Encapsulating peritoneal sclerosis in an Italian center: thirty year experience.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is a rare but life-threatening complication of peritoneal dialysis (PD). Its incidence and prevalence are still not clearly defined. No data exist on the prevalence of EPS in Italy. OBJECTIVES: To evaluate the incidence and prevalence of EPS, and identify potential factors useful for prevention or early diagnosis of EPS. METHODS: A retrospective study in patients starting PD between 1979 and 2013 in one Italian center. Data on demographics, occurrence of EPS, time on PD, peritoneal equilibration test, and therapy for EPS were gathered. RESULTS: EPS occurred in 26/920 patients with a prevalence of 2.8 % and incidence of 1/105 patient-years. The prevalence increased with the time spent on PD: 0.4 % for PD duration <2 years, 3 % (2-4 years), 4 % (4-6 years), 6 % (6-8 years), 8 % (8-10 years), 18 % (10-12 years), 75 % (12-14 years), 67 % (>14 years). EPS prevalence was not higher in PD patients transplanted: 5/172 (2.9 %); only two of them (1.2 %) were diagnosed while with a functioning graft. In only one patient (0.6 %) was the diagnosis made during hemodialysis; the other 23 were diagnosed while still on PD. Mortality due to EPS was 38.5 %, and was associated with PD duration. Therapy with steroids reduced mortality [hazard ratio 0.047 (95 % CI: 0.008-0.273); p < 0.001]. CONCLUSIONS: In our experience the prevalence of EPS is low, but increases progressively with the duration of PD. The transfer to hemodialysis or transplantation does not appear to be a key factor for EPS. Therapy with steroids significantly improves the outcome.

Designing Epidemiology Studies to Determine the Incidence and Prevalence of Encapsulating Peritoneal Sclerosis (EPS).

The reported incidence and prevalence of encapsulating peritoneal sclerosis (EPS) varies markedly between North America, Europe, Japan, and Australia. Although this could reflect differences in clinical practice patterns and access to transplantation as there is no current test for early detection, and some patients may present many years after discontinuation of peritoneal dialysis (PD), there are concerns about under-reporting, particularly for those with milder forms. Currently, only PD vintage has been identified as a significant risk factor for developing EPS, although some patients can develop EPS within months of starting PD. As such, there is a need for epidemiological studies to determine the incidence and prevalence of EPS to allow for patient education and counselling in terms of dialysis modality choice and length of treatment. In addition, carefully designed epidemiological studies could potentially allow for the identification of risk factors and bio-markers that could then be used to identify patients at increased risk of developing EPS in the future. Typically, studies to date have been underpowered with inadequate longitudinal follow-up. We review the different types of epidemiological studies and provide information as to the number of patients to be recruited and the duration of follow-up required to determine the incidence and prevalence of EPS.

Late presentation of encapsulating peritoneal sclerosis following renal transplantation and the potential under-reporting of the incidence and prevalence of encapsulating peritoneal sclerosis.

Encapsulating peritoneal sclerosis is an infrequent but potentially devastating complication of peritoneal dialysis. The reported incidence and prevalence of encapsulating peritoneal sclerosis vary markedly between countries. Currently, peritoneal dialysis vintage remains the major risk factor for encapsulating peritoneal sclerosis, and dialysis vintage differs between countries due to the relative competing risks of transplantation, availability of haemodialysis and peritonitis. However, the diagnosis of encapsulating peritoneal sclerosis is often only established when patients have transferred modality to transplantation or haemodialysis. Switching treatment modality may potentially lead to an under-reporting of encapsulating peritoneal sclerosis, as many countries which collect data on dialysis patients in national registries often have separate registries for dialysis and transplant patients, and this may potentially lead to under-reporting of encapsulating peritoneal sclerosis in patients presenting after renal transplantation. Secondly, the question arises as to how long former peritoneal dialysis patients should be followed before a diagnosis of encapsulating peritoneal sclerosis can be confidently excluded. To highlight this point, we present four cases that developed symptomatic encapsulating peritoneal sclerosis more than 5 years, and in once case more than 10 years after the discontinuation of peritoneal dialysis. Delayed or late presentation may not only delay the diagnosis, but also risk surgical interventions by non-specialists. A more robust system is required to record cases of encapsulating peritoneal sclerosis to determine the incidence and prevalence, and so provide accurate information to both patients and clinicians as to the risks of long-term peritoneal dialysis therapy.

Past and present perspectives on encapsulating peritoneal sclerosis.

Encapsulating peritoneal sclerosis (EPS) is a serious complication of long-term peritoneal dialysis. The mortality rate for EPS has been high, primarily due to complications related to bowel obstruction. However, recent advances in clinical research have established the pathogenesis, the disease course, and a treatment strategy. Currently, there is consensus on therapy; however, treatment with corticosteroids and tamoxifen should be administered in a timely manner. The final therapeutic option for EPS is surgical enterolysis (adhesiolysis). Moreover, a biocompatible peritoneal dialysis solution has become available for patients worldwide, which may further reduce peritoneal deterioration and EPS risk. These activities have promoted a better understanding of and have prompted countermeasures against EPS. EPS is no longer considered a fatal complication.

Accurate definition and management of idiopathic sclerosing encapsulating peritonitis.

AIM: To review the literature on idiopathic sclerosing encapsulating peritonitis (SEP), also known as abdominal cocoon syndrome. METHODS: The PubMed, MEDLINE, Google Scholar, and Google databases were searched using specific key words to identify articles related to idiopathic SEP. These key words were "sclerosing encapsulating peritonitis," "idiopathic sclerosing encapsulating peritonitis," "abdominal cocoon," and "abdominal cocoon syndrome." The search included letters to the editor, case reports, review articles, original articles, and meeting presentations published in the English-language literature from January 2000 to May 2014. Articles or abstracts containing adequate information about age, sex, symptom duration, initial diagnosis, radiological tools, and surgical approaches were included in the study. Papers with missing or inadequate data were excluded. RESULTS: The literature search yielded 73 articles on idiopathic (primary) SEP published in 23 countries. The four countries that published the greatest number of articles were India (n = 21), Turkey (n = 14), China (n = 8) and Nigeria (n = 3). The four countries that reported the greatest number of cases were China (n = 104; 53.88%), India (n = 35; 18.13%), Turkey (n = 17; 8.80%) and Nigeria (n = 5; 2.59%). The present study included 193 patients. Data on age could be obtained for 184 patients (range: 7-87 years; mean ± SD, 34.7 ± 19.2 years), but were unavailable for nine patients. Of the 184 patients, 122 were male and 62 were female; sex data could not be accessed in the remaining nine patients. Of the 149 patients whose preoperative diagnosis information could be obtained, 65 (43.6%) underwent operations for abdominal cocoon, while the majority of the remaining patients underwent operations for a presumed diagnosis of intestinal obstruction and/or abdominal mass. Management information could be retrieved for 115 patients. Of these, 68 underwent excision + adhesiolysis (one laparoscopic); 24 underwent prophylactic appendectomy in addition to excision + adhesiolysis. Twenty patients underwent various resection and repair techniques along with excision + adhesiolysis. The remaining three patients were managed with antituberculosis therapy (n = 2) and immunosuppressive therapy (n = 1). CONCLUSION: Idiopathic SEP is a rare disorder characterized by frequently recurring bouts of intestinal obstruction. Surgical therapy is the gold standard management strategy.

Long-term outcome of encapsulating peritoneal sclerosis (EPS) patients in a single center.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is the most serious complication of peritoneal dialysis (PD) with a high mortality rate. The objective of the present study was to determine the clinical characteristics, the incidence rate, and the long-term outcome of EPS patients compared with control patients. METHODS: Two hundred and seventy patients with end-stage kidney disease were started on PD from 1987 to 2013 in the Juntendo University Hospital. EPS was diagnosed by clinical findings, radiological findings, and macroscopic inspection at the time of laparoscopy or surgical operation. Patient medical records were analyzed retrospectively, including clinical characteristics, laboratory findings, treatment modality, and outcomes. Using a Kaplan-Meier analysis, we compared the survival rate between EPS patients and control PD patients, matched for age, gender, diabetes, and duration of PD. RESULTS: Among 270 PD patients, 13 patients (4.8 %) developed EPS. The mean duration of PD was 120.5 ± 42.8 months. There were no significant difference in demographic findings between EPS and control PD patients. Among the EPS patients, seven patients died, of which four deaths were directly attributed to EPS. All four patients that had had surgical enterolysis were doing well and had no recurrences. No significant difference in the survival rate between EPS and control PD patients was observed in the Kaplan-Meier analysis. CONCLUSIONS: There was no significant difference in the survival rate between EPS patients and control PD patients. It appears that an early diagnosis by laparoscopy and accurate treatment, including surgical enterolysis, might improve mortality.

Histological and clinical findings in patients with post-transplantation and classical encapsulating peritoneal sclerosis: a European multicenter study.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) commonly presents after peritoneal dialysis has been stopped, either post-transplantation (PT-EPS) or after switching to hemodialysis (classical EPS, cEPS). The aim of the present study was to investigate whether PT-EPS and cEPS differ in morphology and clinical course. METHODS: In this European multicenter study we included fifty-six EPS patients, retrospectively paired-matched for peritoneal dialysis (PD) duration. Twenty-eight patients developed EPS after renal transplantation, whereas the other twenty-eight patients were classical EPS patients. Demographic data, PD details, and course of disease were documented. Peritoneal biopsies of all patients were investigated using histological criteria. RESULTS: Eighteen patients from the Netherlands and thirty-eight patients from Germany were included. Time on PD was 78(64-95) in the PT-EPS and 72(50-89) months in the cEPS group (p>0.05). There were no significant differences between the morphological findings of cEPS and PT-EPS. Podoplanin positive cells were a prominent feature in both groups, but with a similar distribution of the podoplanin patterns. Time between cessation of PD to the clinical diagnosis of EPS was significantly shorter in the PT-EPS group as compared to cEPS (4(2-9) months versus 23(7-24) months, p<0.001). Peritonitis rate was significantly higher in cEPS. CONCLUSIONS: In peritoneal biopsies PT-EPS and cEPS are not distinguishable by histomorphology and immunohistochemistry, which argues against different entities. The critical phase for PT-EPS is during the first year after transplantation and therefore earlier after PD cessation then in cEPS.