Prolonged Peritoneal Dialysis Research Articles

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

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. 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. 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. 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.

Mechanisms of human umbilical cord mesenchymal stem cells-derived exosomal lncRNA GAS5 in alleviating EMT of HPMCs via Wnt/β-catenin signaling pathway.

Prolonged peritoneal dialysis (PD) can result in epithelial-to-mesenchymal transition (EMT) and peritoneal fibrosis (PF), which can cause patients to discontinue PD. It is imperative to urgently investigate effective measures to mitigate PF. This study aims to reveal mechanisms of exosomal lncRNA GAS5 derived from human umbilical cord mesenchymal stem cells (hUC-MSCs) on EMT of human peritoneal mesothelial cells (HPMCs) under high glucose (HG) conditions. HPMCs were stimulated with 2.5% glucose. The effects on EMT of HPMCs were observed by using an hUC-MSC conditioned medium (hUC-MSC-CM) and extracted exosomes. After hUC-MSCs were transfected with GAS5 siRNA, exosomes were extracted to act on HPMCs for detecting EMT markers, PTEN, and Wnt/β-catenin pathway, lncRNA GAS5 and miR-21 expressions in HPMCs. We found that HG could induce the EMT of HPMCs. Compared with the HG group, the hUC-MSC-CM could alleviate the EMT of HPMCs induced by HG through exosomes. Exosomes in the hUC-MSC-CM entered HPMCs, by transferring lncRNA GAS5 to HPMCs, which down-regulates miR-21 and up-regulates PTEN, thus finally alleviating EMT of HPMCs. The Wnt/β-catenin pathway plays an essential role in alleviating EMT of HPMCs by exosomes in the hUC-MSC-CM. By transferring lncRNA GAS5 to HPMCs, exosomes derived from hUC-MSCs may competitively bind to miR-21 to regulate suppression on target PTEN genes and alleviate EMT of HPMCs through the Wnt/β-catenin pathway. Exosomes from the hUC-MSCs-CM could alleviate the EMT of HPMCs induced by HG via regulating lncRNA GAS5/miR-21/PTEN through the Wnt/β-catenin signaling pathway.

OC-059 TEMPORARY ABDOMINAL CLOSURE NEGATIVE THERAPY IMPROVES DEFINITIVE FASCIAL CLOSURE RATES IN PATIENTS WITH OPEN ABDOMEN MANAGEMENT

Abstract Aims Encapsulating peritoneal sclerosis (EPS) is a rare phenomenon characterised by encasement of the bowel by a thickened peritoneum due to prolonged peritoneal dialysis exposure. We are an international referral centre, typically managing cases with a planned open abdomen (OAM) and scheduled relook after 24–48 hours. We compare outcomes for those patients whose OAM was with simple packing (betadine-soaked-gauze) with negative pressure therapy providing temporary abdominal closure (TAC). Methods A retrospective review of a contemporaneous database of patients who underwent surgery for EPS between 2010–2020 was performed. Primary endpoints were time to definitive closure and closure method (primary fascial closure vs. bridged biologic mesh closure vs. failure to close fascia). Secondary endpoints included comparison of stoma formation, bowel resection, fistulation rate, enterotomy formation, re-operation post closure, and wound infection. Results 99 patients had OAM (56 static packing; 43 TAC.) Patients with TAC were significantly more likely to undergo primary closure of fascia when compared to those patients managed with static packing, (63% vs 13%, p&amp;lt;0.0001, Chi Sq). The TAC group required fewer theatre episodes (n=2.27 vs. 4.78, p&amp;lt;0.0001, t-test) and time in days to achieve closure (n=2.78 vs n=4.68, p&amp;lt;0.005, Chi Sq), with less failure to close episodes and returns to theatre 30 days post closure. Conclusion This study provides definitive evidence of TAC efficacy for fascial closure following OAM. This provides definitive benefit over traditional open abdominal methods. It may provide benefit in definitive open abdominal management in other areas (sepsis and trauma) and requires further study.

Analysis of risk factors of postoperative mortality in peritoneal dialysis patients with developed peritonitis

Abstract. Peritoneal dialysis (PD)-associated peritonitis can lead to dysfunction in PD delivery as a result of thickening of the peritoneal membrane, usually due to recurrent peritonitis, and result in peritonitis with ileus or intestinal perforation. This study sought to investigate the risk factors that lead to mortality in patients receiving PD who underwent surgery for peritonitis.&#x0D; Methods. The study was designed as a retrospective observational study and included 36 patients who received PD and underwent surgical treatment for peritonitis between 2011 and 2020. Data on patient demographics, comorbid diseases, duration of PD application, number of peritonitis episodes due to PD, surgical procedures performed due to peritonitis, and postsurgical morbidity and mortality rates were collected.&#x0D; Results. It was found that mortality increased with advancing age in patients with coronary artery disease (CAD) compared to those without CAD, and this increase was statistically significant (p = 0.002). In addition, it was determined that the accompanying cirrhosis significantly increased mortality in elderly patients (p = 0.043). In considering the surgical procedures performed, it was found that segmental small-bowel resection (n = 16) was mostly performed due to ileus or intestinal perforation, and no additional pathological findings other than peritonitis were encountered in 12 patients. Mortality occurred in eight patients in the advanced-age group and one patient in the other group among patients operated on for peritonitis. No difference in mortality rate was found according to the surgical procedure (p = 0.512). Binary logistic regression analysis was applied and age, coroner artery diseases (CAD), and dialysis time for risk of mortality. Respectively, age (odds ratio [OR]= 1.09; 95% Cl [1.013-1.193]; p=0.024), CAD [OR] = 43.7; 95% Cl [5.191-368.755]; p &lt;.001 and dialysis time [OR] = 1.786; 95% [1.060-3.010]; p=0.029 was calculated.&#x0D; Conclusions. Mortality increased by 1.09 times for each one-year increase in age after 52.5 years of age and also CAD increased the mortality rate by 43.7 times. Prolonged PD duration increased the mortality rate especially after 11.5 months, increased the peritonitis-related mortality rate by 1.7 times. We propose that since surgical interventions may be performed in peritonitis due to PD; and do not increase peritonitis-related mortality, an appropriate surgical procedure can be performed safely in experienced centers before it is too late.&#x0D;

Assessment of peritoneal thickness using CT in relation to dialysis adequacy in peritoneal dialysis patients

AbstractStudies assessing peritoneal thickness by CT in peritoneal dialysis (PD) patients are lacking. In this study, we aimed to investigate the association between peritoneal thickness as measured by CT and dialysis adequacy with peritoneal membrane characteristics in PD patients. Ninety‐four PD patients were enrolled. Peritoneal thickness was measured by CT. Patients with and without a decrease in Kt/V of at least 0.3 over time were classified as Group 1 and Group 2, respectively. An increase of 0.1 unit of dialysate/plasma (D/P) creatinine over time were considered significant. The relationship between peritoneal membrane thickness, change in Kt/V, and peritoneal membrane characteristics were investigated. There were 31 (33.0%) patients in Group 1. The duration of PD (86.0 ± 64.1 vs. 59.6 ± 45.2 months, p: 0.023), peritoneal thickness (1.02 ± 0.37 vs. 0.87 ± 0.21 mm, p: 0.015), peritoneal calcification (7 [22.6%] vs. 3 [4.8%] patients, p: 0.013], increased D/P creatinine ratio (14 [45.2%] vs. 14 [22.2%] patients, p: 0.031) and CRP (13.9 ± 11.2 vs. 7.1 ± 4.8 mg/L, p: 0.045) were significantly higher in Group 1, whereas albumin (3.6 ± 0.5 vs. 3.8 ± 0.6 g/dL, p: 0.047) and parathyroid hormone (355.2 ± 260.2 vs. 532.1 ± 332.9 ng/L, p: 0.015) levels were significantly lower. Peritoneal thickness was significantly correlated with duration of PD (r: 0.775, p &lt; 0.001) and CRP (r: 0.282, p: 0.006). Regression analysis showed that peritoneal thickness (Exp (B) [95% CI]: 0.029 [0.003–0.253], p: 0.001) was independent predictor of decreased Kt/V in PD patients. In conclusion, prolonged PD duration and increased peritoneal thickness are associated with a decrease in Kt/V over time. CT may be an alternative and noninvasive method instead of peritoneal biopsy for determining the structural changes of the peritoneal membrane .

MO701COMBINED PROCEDURE OF PRE- EXISTING ABDOMINAL WALL HERNIA REPAIR AND PERITONEAL CATHETER INSERTION. LONG TERM FOLLOW- UP IN PERITONEAL DIALYSIS TREATMENT

Abstract Background and Aims Successful peritoneal dialysis (PD) program requires a combination of optimal peritoneal access and low incidence of complications. Between pitfalls of this modality are early mechanical complications such as leak, malfunction, and new abdominal wall hernia formation in the long term of PD treatment. Pre-existing abdominal wall hernia is a relative contraindication for PD. Hernias are also a known and not uncommon complication over the course of PD and one of the causes of technique failure. In our center, a physical examination and an ultrasound for hernias detection are routine procedures before the start of PD. If a hernia is discovered, combined hernia repair and catheter implantation are performed. The aim of this study was to assess to long- term results of this approach. Method The current study presents the retrospective analysis of 10 years' experience of our PD program (1.01.2009 – 31.12. 2018) including all incident PD patients who underwent their first peritoneal catheter placement procedure during the study period. The primary endpoints of the study were the rate of hernia formation in the course of PD treatment, type of hernias, identification risk factors for hernia formation and rate of hernia recurrence after previous repair. The secondary endpoint was the rate of procedure-related complications: infectious, leaks and primary catheter malfunction in patients who underwent surgical catheter insertion compared to percutaneous technique. Patients were followed until the end of PD treatment or until 31.10.2019. Results A total of 211 patients were included in the analysis. Of these, 24.5% underwent surgical procedures and 75.5% percutaneous insertion. Mean follow-up was 23.3 ± 25 months (2 to 96 months). About half (53.1%) of the patients were diabetic, aged 64.2±13 years. In 32 patients (15%) a preventive hernia repair with a simultaneous catheter implantation were performed. Patients who underwent a preventive hernia repair were significantly older than other patients (69.4±11.1 years versus 63.2±13.1 years, P=0.013). During the study period, 203 of 211 patients were treated by PD. Thirty three (16.1%) have developed 38 new hernias. Patients suffering from a new hernia during PD were predominantly male, with longer dialysis vintage than patients without new hernia formation (35.3±22.8 months versus 23±22.9, respectively. P=0.001). Five of 33 patients suffered multiple hernias, including recurrent hernias at the same site. Most common types were inguinal and umbilical (44.7% each other), while only few were incisional or ventral. None of our patients suffered from a pericatheter one. The overall rate of new hernias development was 0.09/patient/years. Neither age, comorbidities, obesity nor polycystic kidney disease did not increase the rate of hernia formation during the course of PD treatment. There was no significant association between type of catheter insertion procedure (surgical/percutaneous) and infections, leakages or catheter function. Leak incidence in diabetic patients was significantly higher in comparison with nondiabetic patients (8% versus 1%, P=0.021). Infectious complications were not different between diabetic and not diabetics patients (5.4% among diabetic patients versus 2% nondiabetic, P=0.29). Conclusion Our findings show that male gender and prolonged peritoneal dialysis duration are the main risk factors for the appearance of hernias in the course of PD therapy. Our data also confirm previous observations that the placement of PD catheter using a paramedian incision approach significantly reduces the incidences of exit site and incision hernias. We suggest that early diagnosis of latent asymptomatic hernias and hernia repair prior to starting PD can improve technique survival.

Proposal of peritoneal biopsy procedures for patients undergoing peritoneal dialysis

Prolonged peritoneal dialysis (PD) is responsible for progressive morphological changes such as deterioration of the peritoneal membrane. These changes increase the risk of encapsulating peritoneal sclerosis (EPS). Histological assessments of peritoneal membrane biopsy samples are fundamental for the evaluation of the peritoneal damage caused by PD. For evaluating serial morphological changes induced in the peritoneum by PD, we recommend to perform peritoneal biopsy examinations not only after the cessation of PD but also before performing PD. At the time of PD catheter insertion, the parietal peritoneum (1.5 × 1.5 cm) and rectus abdominal muscle posterior sheath is sampled at a point 3 cm below the PD catheter insertion site. Furthermore, at the time of PD catheter removal, the parietal peritoneum is sampled at a point 3 cm apart from the PD catheter insertion site to avoid artifacts. The peritoneum should be evaluated to detect mesothelial cell denudation, acellular sclerotic changes and thickness of the submesothelial connective tissue, vasculopathy of the post-capillary venules, vascular angiogenesis, and new encapsulating membrane. The method presented herein allows the minimization of surgical invasiveness and artifacts of the specimens and safe performance of peritoneal biopsy examinations. Morphological evaluation of the peritoneum involving an appropriate biopsy strategy, in conjunction with functional markers of deterioration, such as peritoneal permeability or cytokine levels, is a useful approach for examining peritoneal damage and predicting the prognosis of PD patients, especially the onset of EPS.

Peritoneal Dialysis in Pediatric Postoperative Cardiac Surgical Patients.

ABSTRACTBackgroundWe determined the prevalence of acute kidney injury requiring peritoneal dialysis (PD), the factors associated with early PD initiation, prolonged PD and mortality among pediatric postoperative cardiac surgical patients.Materials and MethodsThe hospital records of 23 children, aged 12 years or younger, who had undergone cardiac surgery and required PD subsequently, during a 1-year period were reviewed. Demographic data, intraoperative variables, and postoperative complications were compared between survivors and nonsurvivors of PD, between the short and long duration PD groups, and between the early and late PD initiation groups.ResultsSix hundred and eight pediatric patients who underwent open heart surgery were enrolled in this study. 23 (3.78%) of them required PD. When compared with survivors (n = 11), non survivors (n =12) were more likely to have a higher serum procalcitonin (p = 0.01), higher serum potassium on day 2 (p = 0.001), day 3 (p = 0.04), day of termination of PD (p = 0.001) and a lower urine output on day 3 of PD (p = 0.03). Prolonged PD was associated with time of PD initiation (p = 0.01), a higher postoperative serum creatinine on day 3 (p = 0.01) of PD initiation as well on the day of PD termination (p = 0.01) and the final outcome in terms of survival (p = 0.02). Factors significantly associated with an early PD initiation were CPB time (p = 0.04), sepsis (p = 0.02) and shorter PD duration (p = 0.003).ConclusionPD is very useful mode of renal replacement therapy among pediatric postoperative cardiac surgical patients. The intraoperative and postoperative variables have important association with the time of PD initiation, PD duration and patient survival.How to cite this articleSahu MK, Bipin C, Arora Y, Singh SP, Devagouru V, Rajshekar P, et al. Peritoneal Dialysis in Pediatric Postoperative Cardiac Surgical Patients. Indian J Crit Care Med 2019;23(8):371–375.

Furosemide Response Predicts Acute Kidney Injury After Cardiac Surgery in Infants and Neonates.

Cardiac surgery-induced acute kidney injury occurs frequently in neonates and infants and is associated with postoperative morbidity/mortality; early identification of cardiac surgery-induced acute kidney injury may be crucial to mitigate postoperative morbidity. We sought to determine if hourly or 6-hour cumulative urine output after furosemide in the first 24 hours after cardiopulmonary bypass could predict development of cardiac surgery-induced acute kidney injury and other deleterious outcomes. Retrospective chart review. Pediatric cardiac ICU. All infants younger than 90 days old admitted to the cardiac ICU from October 2012 to December 2015 who received at least one dose of furosemide in the first 24 hours after cardiopulmonary bypass surgery. None. Ninety-nine patients met inclusion and exclusion criteria. In total, 45.5% developed cardiac surgery-induced acute kidney injury. Median time between cardiopulmonary bypass and furosemide was 7.7 hours (interquartile range, 4.4-9.5). Six-hour cumulative urine output was 33% lower (p = 0.031) in patients with cardiac surgery-induced acute kidney injury. Area under the curve for prediction of cardiac surgery-induced acute kidney injury was 0.69 (p = 0.002). Other models demonstrated urine output response to furosemide had significant area under the curves for prediction of peak fluid over load greater than 15% (0.68; p = 0.047), prolonged peritoneal dialysis (area under the curve, 0.79; p = 0.007), prolonged mechanical ventilation (area under the curve, 0.79; p < 0.001), prolonged hospitalization (area under the curve, 0.62; p = 0.069) and mortality (area under the curve, 0.72; p = 0.05). Urine output response to furosemide within 24 hours of cardiopulmonary bypass predicts cardiac surgery-induced acute kidney injury development and other important morbidity in children younger than 90 days old; prospective validation is warranted.

Clinical efficacy of combined therapy with peritoneal dialysis and hemodialysis

Combined therapy with peritoneal dialysis (PD) and hemodialysis (HD) represents a treatment option for PD patients who cannot maintain adequate solute and fluid removal. It has rapidly gained popularity in Japan, and 15 years of accumulated experiences is available. Serum creatinine, serum β2 microglobulin (β2m), body weight, and blood pressure decreased, whereas hemoglobin increased after initiating combined therapy. These results indicated that both adequacy of dialysis and hydration status were significantly improved. In addition, dialysate-to-plasma ratio of creatinine (D/P Cr) as obtained from peritoneal equilibration test (PET) was decreased, probably due to the functional and histological improvements of the peritoneal membrane. Combined therapy may have a good impact on the prevention of cardiovascular disease through reduction of blood pressure, correction of fluid overload, and improvement of left ventricular hypertrophy. Quality of life may improve as a result of decreases in uremic symptomatology and freedom from bag exchanges. On the other hand, combined therapy with PD and HD has some concerns. A reduction in urine volume during combined therapy indicates a decline in residual renal function, and may have potential negative impacts on life expectancy. Furthermore, induction of combined therapy would increase the overall duration of PD treatment and susceptibility to peritonitis. We have to pay attention to the development of encapsulating peritoneal sclerosis, as the most serious complication of PD, because both prolonged PD duration and increased number of peritonitis episodes are independent risk factors. Here, we propose criteria for the indication and discontinuation of combined therapy. Under these criteria, Kt/V, serum β2m, and uremic symptoms including nutritional status, erythropoiesis-stimulating agent-hyporesponsive anemia, and restless legs syndrome were used as markers of dialysis adequacy. On the other hand, higher blood pressure, heart enlargement or pleural effusion on chest X-ray, and persistent peripheral edema were used as markers of hydration status. Further studies, particularly prospective cohort studies with a large group of cases, are needed to confirm the clinical efficacy of combined therapy with PD and HD.

The Risk Factors and the Impact of Hernia Development on Technique Survival in Peritoneal Dialysis Patients: A Population-Based Cohort Study

There is a lack of consensus on the risk factors for hernia formation, and the impact on peritoneal dialysis (PD) survival has seldom been studied. This was a population-based study and all collected data were retrieved from the National Health Insurance Research Database of Taiwan. Patients who commenced PD between January 1998 and December 2006 were screened for inclusion. Multiple logistic regression and Cox proportional hazards models were applied to estimate the predictors for hernia formation and determine the predictors of PD withdrawal. A total of 6,928 PD patients were enrolled and followed until December 2009, with 631 hernia events and 391 hernioplasties being registered in 530 patients (7.7%). The incidence rate was 0.04 hernias/patient/year. Longer PD duration (per 1 month increase, hazard ratio (HR) 1.019) and history of mitral valve prolapse (MVP) (HR 1.584) were independent risk factors for hernia formation during PD, and female gender (HR 0.617) was a protective factor. On the other hand, there were 4,468 PD withdrawals, with cumulative incidence rates of 41% at 1 year, 66% at 3 years, and 82% at 5 years. Independent determinants for cumulative PD withdrawal included hernia formation during PD (HR 1.154), age (per 1 year increase, HR 1.014), larger dialysate volume (per 1 liter increase, HR 0.496), female gender (HR 0.763), heart failure (HR 1.092), hypertension (HR 1.207), myocardial infarction (HR 1.292), chronic obstructive pulmonary disease (COPD) (HR 1.227), cerebrovascular accident (CVA) (HR 1.364), and history of MVP (HR 0.712) CONCLUSIONS: Prolonged PD duration was a risk factor for hernia formation, and female gender was protective. Hernia formation during PD therapy may increase the risk of PD withdrawal.

Metabolite characterisation in peritoneal dialysis effluent using high-resolution (1) H and (1) H-(13) C NMR spectroscopy.

Metabolite analysis of peritoneal dialysis (PD) effluent may provide information regarding onset and progression of complications associated with prolonged PD therapy. In this context, the nuclear magnetic resonance detectable small metabolites of PD effluent samples were characterised using high-resolution (1) H and (1) H-(13) C NMR spectroscopy. The various spectra were recorded (at 800 MHz proton frequency) on PD effluent samples obtained after 4-h (intraperitoneal) dwell time from patients with end-stage renal failure and continuing normally on PD therapy. In spite of devastating spectral feature of PD effluent due to the presence of intense resonances from glucose and lactate, we were able to identify 53 small endogenous metabolites (including many complex coupled spin systems) and more than 90% of the total CH cross peaks of (1) H-(13) C heteronuclear single-quantum correlation spectrum specific to various metabolites of PD effluent. We foresee that the characteristic fingerprints of various metabolites of control PD effluent samples will be used to identify and distinguish metabolic differences from PD-related complications.

Accumulation of advanced glycation end products and beta 2-microglobulin in fibrotic thickening of the peritoneum in long-term peritoneal dialysis patients

Characteristics of pathological alterations in long-term peritoneal dialysis (PD) are thickening of submesothelial compact (SMC) zone, small-vessel vasculopathy, and loss of mesothelial cells. Bioincompatible PD fluid plays crucial roles in peritoneal injury. Encapsulating peritoneal sclerosis (EPS), a rare and serious complication, occurred in patients on long-term PD or frequent peritonitis episodes, and ~50 % of EPS developed after PD cessation. We hypothesized that PD-related peritoneal injury factors induced by bioincompatible PD fluid accumulated in the peritoneum and might induce EPS. We therefore examined the accumulation of advanced glycation end products (AGE) and beta 2-microglobulin (β2M) in peritoneum and evaluated the relationship between their accumulation, clinical parameters, and outcome after PD cessation. Forty-five parietal peritoneal specimens were obtained from 28 PD patients, 14 uremic patients, and three patients with normal kidney function. The peritoneal equilibration test was used for peritoneal function. AGE- and β2M-expressing areas were found in vascular walls, perivascular areas, and the deep layer of the SMC in short-term PD patients and extended over the entire SMC in long-term patients. Peritonitis and prolonged PD treatment aggravated peritoneal thickening and the proportion of AGE-expressing areas. The proportion of β2M-expressing areas was increased in long-term PD patients. Thickening of the SMC and the proportions of AGE- and β2M-expressing areas were not related to ascites or EPS after PD withdrawal. It appears that the increased proportion of AGE and β2M deposition induced by long-term exposure of PD fluid may be a marker of peritoneal injury.

Anti-C5a complementary peptide ameliorates acute peritoneal injury induced by neutralization of Crry and CD59

In peritoneal dialysis (PD) therapy, physical stresses such as exposure to peritoneal dialysate, catheter trauma, and peritonitis may induce peritoneal injury that can prevent continued long-term PD therapy. Therefore, protection of the peritoneum is an important target to enable long-term PD therapy in patients with end-stage renal disease. We previously showed that neutralization of the membrane complement regulators (CRegs) Crry and CD59 in rat peritoneum provokes development of acute peritoneal injury due to uncontrolled complement activation. C5a is a key effecter molecule of the complement system released during acute inflammation. Control of C5a has been proposed as a strategy to suppress inflammatory reactions and, because peritoneal injury is accompanied by inflammation, we hypothesized that C5a targeted therapy might be an effective way to suppress peritoneal injury. In the present study we used an established acute peritonitis model induced by neutralization of CRegs to investigate the effects on acute peritoneal injury of inhibiting C5a. Intravenous administration of an anti-C5a complementary peptide (AcPepA) up to 4 h after induction of injury significantly and dose-dependently prevented accumulation of inflammatory cells and reduced tissue damage in the model, accompanied by decreased C3b deposition. We show that C5a contributed to the development of peritoneal injury. Our results suggest that C5a is a target for preventing or treating peritoneal injury in patients undergoing prolonged PD therapy or with infectious complications.

Sclerosing peritonitis, a rare complication after intestinal transplant. Report of one case successfully treated with adjustment of immunosuppression

Sclerosing peritonitis is a complication described in different clinical situations, such as patients that underwent prolonged peritoneal dialysis or renal transplantation with previous history of peritoneal dialysis. The origin of this entity is unclear so far and it is believed that several mechanisms may contribute to its development. The hallmark of sclerosing peritonitis is the continuous accumulation of fibrocollagenous deposits in the intestinal wall and mesenteries causing progressive adhesion of the intestinal loops and mesenteric retraction resulting in intestinal obstruction. Also, it has been described as a rare complication after intestinal transplant that might lead to graft failure. In this report, we describe a case of sclerosing peritonitis after intestinal transplantation that was successfully treated with modifications in the immunosuppressive regime allowing restitution of gastrointestinal transit and intestinal autonomy.

Early Initiation of Peritoneal Dialysis after Arterial Switch Operations in Newborn Patients

Background and aim: We investigated the clinical outcome of early initiated peritoneal dialysis (PD) use in our newborn patients who underwent arterial switch operation (ASO) for transposition of the great arteries (TGA) and had routine intraoperative PD catheter implantation. We determined the risk factors for PD, factors associated with prolonged PD, morbidity, and mortality. The aim of the present study was to describe our experience of using PD in this patient cohort. Materials and Methods: Eighty two patients who were diagnosed with TGA and TGA-ventricular septal defect (VSD) and who had undergone TGA correction operation in Başkent University, Istanbul Medical Research and Training Hospital between 2007 and 2012 were retrospectively investigated. All the patients were under 30 days old. PD catheters were routinely implanted intraoperatively at the end of the operation. PD was initiated in transient renal insufficiency. In the absence of oliguria and increased creatinine level, PD was established in the presence of one of the following: clinical signs of fluid overload, hyperkalemia (>5 mEq/L), persistent metabolic acidosis, lactate level above 8 mmol/L or low cardiac output syndrome. The patients were divided into two groups according to the need for postoperative PD (PD group and non-PD group). PD was initiated in 32 (39%) patients after the operation, whereas 50 (61%) patients did not need dialysis. The clinical outcomes and perioperative data of the two groups were compared. Results: The demographics in the two groups were similar. Cardiopulmonary bypass time was longer in the PD group [non-PD group, 175.24 ± 32.39 min; PD group, 196.22 ± 44.04 min (p < 0.05)]. Coronary anomaly was found to be higher in the PD group [non-PD group, n = 2 patients (4.0%); PD group, n = 7 patients (21.9%); p < 0.05]. There was more need for PD in TGA + VSD patients [simple TGA patients, n = 14; TGA + VSD patients, n = 18 (p < 0.05)]. PD rate was higher in patients whose sterna were left open at the end of the operation (p < 0.05). The ventilator time [non-PD group, 4.04 ± 1.51 days; PD group, 8.12 ± 5.21 days (p < 0.01)], intensive care unit stay time [non-PD group, 7.98 ± 5.80 days; PD group, 15.93 ± 18.31 days (p < 0.01)], and hospital stay time were significantly longer in the PD group [non-PD group, 14.98 ± 10.14 days; PD group, 22.84 ± 20.87 days (p < 0.01)]. Conclusion: We advocate routine implantation of PD catheters to patients with TGA-VSD, coronary artery anomaly, and open sternum in which we have determined high rate of postoperative PD need.

Proof-of-principle study to detect metabolic changes in peritoneal dialysis effluent in patients who develop encapsulating peritoneal sclerosis

Prolonged peritoneal dialysis (PD) therapy can result in the development of encapsulating peritoneal sclerosis (EPS), characterized by extensive sclerosis of the peritoneum with bowel adhesions often causing obstruction. As a proof-of-principle study, holistic profiling of endogenous metabolites has been applied in a prospective collection of PD effluent collected in multiple UK renal centres over 6 years in order to investigate metabolic differences in PD effluent between PD therapy patients who later developed clinically defined EPS (n = 11) and controls, who were matched for PD vintage, age and gender (n = 11). 'Fit-for-purpose' analytical methods employing gas chromatography-mass spectrometry (MS), direct injection MS and quality control samples were developed and validated. These methods were applied in a proof-of-principle study to define metabolic differences in PD effluent related to subsequent development of EPS. Changes in amino acids, amines and derivatives, short-chain fatty acids and derivatives and sugars were observed prior to EPS developing, and changes in the metabolomic profiles could be detected. There is potential for applying metabolic profiles to identify patients at risk of developing EPS although long-term prospective studies with larger patient cohorts are required.

Peritoneal Dialysis in Infants and Children After Open Heart Surgery

Infants and children who undergo surgical repair of complex congenital heart diseases are prone to developing renal dysfunction. The purpose of this study was to investigate the risk factors associated with prolonged peritoneal dialysis (PD) and the mortality of pediatric patients with acute renal failure (ARF) after open heart surgery. From June 1999 to May 2007, a total of 542 children underwent open heart surgery for congenital heart disease. Fifteen (2.8%) experienced ARF and seven (1.3%) required PD. The clinical and laboratory variables were compared between the survivor and non-survivor groups of ARF patients that needed PD. The non-survivors (n=3, 43%) had a Longer cardiopulmonary bypass time (154+/-21 vs. 111+/-8 minutes, p=0.012) and longer aorta clamping time (92+/-40 vs. 66+/-15 minutes, p=0.010) than the survivors (n=4, 57%). Before the PD, the pH and base excess of the arterial blood gas analysis in the survivors was much higher than that non-survivors (7.30+/-0.04 vs. 7.16+/-0.10, p=0.039; -5.15+/-3.13 vs. -12.07+/-2.9mmol/L, p=0.031). Furthermore, the survivors had a shorter interval between the onset of ARF and the day the PD was begun (1.2+/-0.4 vs. 4.3+/-1.2 days, p=0.001), and shorter duration of PD (6.6+/-2.7 vs. 13.0+/-3.5 days, p=0.036) than non-survivors. Early intervention with PD is a safe and effective method for managing patients with ARF after open heart surgery. The cardiopulmonary bypass and aortic clamping duration, time of initiating PD, duration of the PD, sepsis, and relative complications may predict the prognosis of these patients.

The relationship between bone morphogenic protein-7 and peritoneal transport characteristics

After prolonged peritoneal dialysis (PD) and exposure to a non-physiological dialysis solution, peritoneal mesothelial cells undergo the epithelial-to-mesenchymal transition. In other biological systems, bone morphogenic protein-7 (BMP-7) is a key factor that controls this process. However, the role of BMP-7 in peritoneal physiology has not been studied. We studied the peritoneal transport characteristics of 50 consecutive new PD patients at 4 and 52 weeks after PD. Peritoneal permeability will be determined by the standard peritoneal equilibration test (PET). BMP-7 in PD effluent (PDE) at mRNA and protein level at 4 weeks was quantified. At 4 weeks, the mRNA expression of BMP-7 in PDE significantly correlated with peritoneal transport characteristics, including the dialysate-to-plasma creatinine ratio at 4 h (D/P4) (r = 0.422, P = 0.015) and mass transfer area coefficient (MTAC) of creatinine (r = 0.457, P = 0.008). The PDE BMP-7 level by ELISA also had marginal correlation with D/P4 (r = 0.287, P = 0.072) and MTAC creatinine (r = 0.287, P = 0.073), although the result did not reach statistical significance. For the subgroup of patients who remained free of peritonitis, the PDE BMP-7 level by ELISA had significant correlation with the change in D/P4 (r = 0.441, P = 0.017) and MTAC creatinine in 52 weeks (r = 0.415, P = 0.025). The PDE BMP-7 level remained independently associated with the change in peritoneal transport adjusting for age, sex, serum C-reactive protein and PDE transforming growth factor-beta level. In patients who had peritonitis during the study period, the PDE BMP-7 level did not affect the change in peritoneal transport. Conclusion. We find that the peritoneal BMP-7 level correlates with peritoneal transport characteristics, and a high PDE BMP-7 level is associated with a gradual increase in peritoneal transport parameters with time. It remains unclear, however, whether this effect is beneficial, and the therapeutic role of exogenous BMP-7 on peritoneal transport requires a further study.

An emerging and devastating acute abdomen in a patient under peritoneal dialysis: encapsulating peritoneal sclerosis

Peritoneal dialysis (PD) has been applied to patients with end-stage renal disease for more than 2 decades. It should raise physicians' concern about the serious complications of prolonged PD therapy, particularly encapsulating peritoneal sclerosis (EPS), the most potentially life-threatening one. The prevalence and mortality rate of EPS increase as PD duration increases. We report a case of EPS presented with blood-tinged effluents and abdominal pain.