Effects of long-term treatment with low-GDP, pH-neutral solutions on peritoneal membranes in peritoneal dialysis patients

Osteoprotegerin and Inflammation in Incident Peritoneal Dialysis Patients

Objectives: Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor family involved in processes in many inflammatory states. OPG concentration is enhanced in the majority of chronic kidney disease (CKD) patients and those undergoing renal replacement therapy. The aim of the study was to assess the relation of OPG and chronic inflammation in peritoneal dialysis (PD) patients and to evaluate whether OPG concentrations in plasma and dialysate were related to plasma and dialysate levels of proinflammatory mediators (interleukin 6 (IL-6), high-sensitivity C-reactive protein (hsCRP), interleukin 33 (IL-33) and interleukin 1 receptor-like 1IL-1RL1 (IL-1RL1, sST2)). Methods: The study included 37 patients of the Peritoneal Dialysis Center, Department of Nephrology, Transplantology and Internal Medicine, Szczecin, Poland, 4-6 weeks after the onset of peritoneal dialysis therapy. During a peritoneal equilibration test, plasma (at 2 h) and dialysate (at 4 h) OPG, IL-33, 1IL-1RL1 (sST2), IL-6 and hsCRP concentrations were determined. Results: Plasma concentration of OPG did not correlate with dialysate OPG level (Rs = 0.04, p = 0.8). There was a strong positive correlation between plasma OPG concentrations and plasma IL-1RL1 (sST2) (Rs = 0.41; p = 0.01), plasma IL-6 (Rs = 0.38; p = 0.01) and plasma hsCRP (Rs = 0.35; p = 0.02). Dialysate OPG concentrations were positively associated with dialysate IL-1RL1 (sST2) (Rs = 0.37; p = 0.02) and dialysate IL-6 levels (Rs = 0.44; p = 0.005). Multivariate analysis showed that higher IL-1RL1 (sST2) (ß = +0.38, p = 0.006), higher plasma hsCRP (ß = +0.32, p = 0.02) and older age (ß = +0.35, p = 0.01) were independent determinants of higher plasma OPG concentration and that higher concentrations of dialysate IL-6 (ß = +0.37, p = 0.02) were independent determinants of higher dialysate OPG concentration. Conclusions: Both plasma and dialysate OPG levels are associated with the severity of systemic and local inflammation illustrated by the plasma and dialysate concentrations of IL-1RL1 (sST2), hsCRP and IL-6, suggesting that OPG might have a pivotal role in explaining the milieu of systemic and intraperitoneal inflammation.

Role of endothelial hyaluronan in peritoneal membrane transport and disease conditions during peritoneal dialysis

Peritoneal membrane dysfunction in peritoneal dialysis (PD) is primarily attributed to angiogenesis; however, the integrity of vascular endothelial cells can affect peritoneal permeability. Hyaluronan, a component of the endothelial glycocalyx, is reportedly involved in preventing proteinuria in the normal glomerulus. One hypothesis suggests that development of encapsulating peritoneal sclerosis (EPS) is triggered by protein leakage due to vascular endothelial injury. We therefore investigated the effect of hyaluronan in the glycocalyx on peritoneal permeability and disease conditions. After hyaluronidase-mediated degradation of hyaluronan on the endothelial cells of mice, macromolecules, including albumin and β2 microglobulin, leaked into the dialysate. However, peritoneal transport of small solute molecules was not affected. Pathologically, hyaluronan expression was diminished; however, expression of vascular endothelial cadherin and heparan sulfate, a core protein of the glycocalyx, was preserved. Hyaluronan expression on endothelial cells was studied using 254 human peritoneal membrane samples. Hyaluronan expression decreased in patients undergoing long-term PD treatment and EPS patients treated with conventional solutions. Furthermore, the extent of hyaluronan loss correlated with the severity of vasculopathy. Hyaluronan on endothelial cells is involved in the peritoneal transport of macromolecules. Treatment strategies that preserve hyaluronan in the glycocalyx could prevent the leakage of macromolecules and subsequent related complications.

Effect of different dialysis duration on the prognosis of peritoneal dialysis-associated peritonitis: a single-center, retrospective study

BACKGROUND

Peritoneal dialysis (PD)-associated peritonitis is a serious complication observed in peritoneal dialysis patients. Herein, we investigated the clinical characteristics and treatment outcomes of PD peritonitis in patients with different PD durations.

METHODS

All peritonitis episodes from January 2007 to December 2020 at Peking University People's hospital PD center were retrospectively analyzed and divided into the long-dialysis duration (≥60 months, LDD) and short-dialysis duration (<60 months, SDD) groups. Clinical characteristics and outcomes were compared between these groups. The risk factors for treatment failure were analyzed using a logistic regression model.

RESULTS

During 14 years, 156 patients had 267 peritonitis episodes. There were 83 (31.1%) peritonitis episodes in the LDD group and 184 (68.9%) in the SDD group. No statistical difference was noted in peritonitis causes and the composition of causative pathogens between the two groups. The hospitalization, treatment failure, and transfer-to-hemodialysis rates, and peritonitis-related mortality were significantly higher in the LDD group than in the SDD group (all p < .05). Logistic regression analysis revealed that PD duration was an independent risk factor for PD-associated hospitalization, treatment failure and peritonitis-related death (p < .05). The receiver operating characteristic curve analysis results showed that when the cutoff value of PD duration was 5.5 years, the sensitivity of predicting PD peritonitis treatment failure was 51.1%, specificity was 78.8%, and the area under the curve was 0.679 (95% confidence interval: 0.594-0.765, p < .001).

CONCLUSIONS

PD duration is an independent risk factor for poor prognosis in PD peritonitis. Careful and active attention should be paid to the prevention of peritonitis in PD patients with long PD duration.

Peritoneal Expression of Membrane Complement Regulators Is Decreased in Peritoneal Dialysis Patients with Infected Peritonitis

In peritoneal dialysis (PD) patients, fungi and Pseudomonas aeruginosa are considered important causative microorganisms for peritonitis with poor prognosis. Our objective was to explore expressions of membrane complement (C) regulators (CRegs) and tissue injuries in the peritoneum of patients with PD-related peritonitis, including fungal and Pseudomonas aeruginosa peritonitis. In peritoneal biopsy tissues obtained at PD catheter removal, we investigated the severity of peritonitis-associated peritoneal injuries and the expression of CRegs, CD46, CD55, and CD59 against peritoneal tissues without any episode of peritonitis. In addition, we evaluated peritoneal injuries among fungal and Pseudomonas aeruginosa-peritonitis (P1) and Gram-positive bacterial peritonitis (P2). We also observed deposition of C activation products such as activated C and C5b-9 and measured sC5b-9 in the PD fluid of patients. As a result, the severity of peritoneal injuries correlated inversely with the expression of peritoneal CRegs. Peritoneal CReg expression in peritonitis was significantly reduced compared to no peritonitis. Peritoneal injuries were more severe in P1 than in P2. CReg expression was further decreased and C5b-9 further increased in P1 than in P2. In conclusion, severe peritoneal injuries due to fungal and Pseudomonas aeruginosa-peritonitis decreased CReg expression and increased deposition of activated C3 and C5b-9 in the peritoneum, suggesting that peritonitis, particularly fungal and Pseudomonas aeruginosa-peritonitis, might induce susceptibility to further peritoneal injuries due to excessive C activation.

Relationship between laparoscopic and microscopic findings of peritoneum in peritoneal dialysis patients

Long-term exposure to the peritoneal dialysis solution (PDS) causes functional and morphological alterations that diminish the efficacy of peritoneal dialysis (PD). Macroscopic and microscopic findings, submesothelial compact zone (SMC) thickness and vascular patency, were associated with PD duration. The relationship between microscopic and laparoscopic morphological findings in PD patients was determined. A total of 78 laparoscopic intraperitoneal findings were recorded during PD catheter removal and 45 peritoneal tissues were obtained from the anterior parietal peritoneum. We examined macroscopic morphological findings in both parietal and visceral peritoneums and bowel movement and assessed the score semiquantitatively. SMC thickness and vascular patency were examined as microscopic findings. Total laparoscopic finding's score (LFS) and microscopic findings, SMC thickness and vascular patency, were associated with PD duration. Total LFS was related to SMC thickness in both visceral and parietal peritoneum, whereas it was related to vascular patency in parietal but not in visceral peritoneum. There was no relationship between microscopic findings and peritoneal surface color, properties, vasculopathy, and adhesion. Total LFS in patients with newly formed membrane and omentum atrophy was higher than in those without. There was a significant relationship between microscopic and laparoscopic findings in PD patients. It is important to evaluate laparoscopic findings in more PD patients to find the predictive findings of encapsulating peritoneal sclerosis development.

How peritoneal dialysis transforms the peritoneum and vasculature in children with chronic kidney disease-what can we learn for future treatment?

Children with chronic kidney disease (CKD) suffer from inflammation and reactive metabolite-induced stress, which massively accelerates tissue and vascular aging. Peritoneal dialysis (PD) is the preferred dialysis mode in children, but currently used PD fluids contain far supraphysiological glucose concentrations for fluid and toxin removal and glucose degradation products (GDP). While the peritoneal membrane of children with CKD G5 exhibits only minor alterations, PD fluids trigger numerous molecular cascades resulting in major peritoneal membrane inflammation, hypervascularization, and fibrosis, with distinct molecular and morphological patterns depending on the GDP content of the PD fluid used. PD further aggravates systemic vascular disease. The systemic vascular aging process is particularly pronounced when PD fluids with high GDP concentrations are used. GDP induce endothelial junction disintegration, apoptosis, fibrosis, and intima thickening. This review gives an overview on the molecular mechanisms of peritoneal and vascular transformation and strategies to improve peritoneal and vascular health in patients on PD.

Angiogenic Role of Mesothelium-Derived Chemokine CXCL1 During Unfavorable Peritoneal Tissue Remodeling in Patients Receiving Peritoneal Dialysis as Renal Replacement Therapy

Peritoneal dialysis (PD) is a valuable ‘home treatment’ option, even more so during the ongoing Coronavirus pandemic. However, the long-term use of PD is limited by unfavourable tissue remodelling in the peritoneal membrane, which is associated with inflammation-induced angiogenesis. This appears to be driven primarily through vascular endothelial growth factor (VEGF), while the involvement of other angiogenic signaling pathways is still poorly understood. Here, we have identified the crucial contribution of mesothelial cell-derived angiogenic CXC chemokine ligand 1 (CXCL1) to peritoneal angiogenesis in PD. CXCL1 expression and peritoneal microvessel density were analysed in biopsies obtained by the International Peritoneal Biobank (NCT01893710 at www.clinicaltrials.gov), comparing 13 children with end-stage kidney disease before initiating PD to 43 children on chronic PD. The angiogenic potential of mesothelial cell-derived CXCL1 was assessed in vitro by measuring endothelial tube formation of human microvascular endothelial cells (HMECs) treated with conditioned medium from human peritoneal mesothelial cells (HPMCs) stimulated to release CXCL1 by treatment with either recombinant IL-17 or PD effluent. We found that the capillary density in the human peritoneum correlated with local CXCL1 expression. Both CXCL1 expression and microvessel density were higher in PD patients than in the age-matched patients prior to initiation of PD. Exposure of HMECs to recombinant CXCL1 or conditioned medium from IL-17-stimulated HPMCs resulted in increased endothelial tube formation, while selective inhibition of mesothelial CXCL1 production by specific antibodies or through silencing of relevant transcription factors abolished the proangiogenic effect of HPMC-conditioned medium. In conclusion, peritoneal mesothelium-derived CXCL1 promotes endothelial tube formation in vitro and associates with peritoneal microvessel density in uremic patients undergoing PD, thus providing novel targets for therapeutic intervention to prolong PD therapy.

Do low GDP neutral pH solutions prevent or retard peritoneal membrane alterations in long-term peritoneal dialysis?

Several studies have been published in the last decade on the effects of low glucose degradation product (GDP) neutral pH (L-GDP/N-pH) dialysis solutions on peritoneal morphology and function during the long-term PD treatment. Compared to conventional solutions, the impact of these solutions on the morphological and functional alterations of the peritoneal membrane is discussed, including those of effluent proteins that reflect the status of peritoneal tissues. Long-term PD with conventional solutions is associated with the loss of mesothelium, submesothelial and interstitial fibrosis, vasculopathy, and deposition of advanced glycosylation end products (AGEs). L-GDP/N-pH solutions mitigate these alterations, although vasculopathy and AGE deposition are still present. Increased vascular density was found in some studies. Small solute transport increases with PD duration on conventional solutions. Initially, higher values are present on L-GDP/N-pH treatment, but these may be reversible and remain stable with PD duration. Consequently, ultrafiltration (UF) is lower initially but remains stable thereafter. At 5 years, UF and small pore fluid transport are higher, while free water transport decreased only slightly during follow-up. Cancer antigen 125 was initially higher on L-GDP/N-pH solutions, suggesting better mesothelial preservation but decreased during follow-up. Therefore, L-GDP/N-pH solutions may not prevent but reduce and retard the peritoneal alterations induced by continuous exposure to glucose-based dialysis fluids.

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.

Low-GDP, pH-neutral solutions preserve peritoneal endothelial glycocalyx during long-term peritoneal dialysis

BACKGROUND

During peritoneal dialysis (PD), solute transport and ultrafiltration are mainly achieved by the peritoneal blood vasculature. Glycocalyx lies on the surface of endothelial cells and plays a role in vascular permeability. Low-glucose degradation product (GDP), pH-neutral PD solutions reportedly offer higher biocompatibility and lead to less peritoneal injury. However, the effects on the vasculature have not been clarified.

METHODS

Peritoneal tissues from 11 patients treated with conventional acidic solutions (acidic group) and 11 patients treated with low-GDP, pH-neutral solutions (neutral group) were examined. Control tissues were acquired from 5 healthy donors of kidney transplants (control group). CD31 and ratio of luminal diameter to vessel diameter (L/V ratio) were evaluated to identify endothelial cells and vasculopathy, respectively. Immunostaining for heparan sulfate (HS) domains and Ulex europaeus agglutinin-1 (UEA-1) binding was performed to assess sulfated glycosaminoglycans and the fucose-containing sugar chain of glycocalyx.

RESULTS

Compared with the acidic group, the neutral group showed higher CD31 positivity. L/V ratio was significantly higher in the neutral group, suggesting less progression of vasculopathy. Both HS expression and UEA-1 binding were higher in the neutral group, whereas HS expression was markedly more preserved than UEA-1 binding in the acidic group. In vessels with low L/V ratio, which were found only in the acidic group, HS expression and UEA-1 binding were diminished, suggesting a loss of glycocalyx.

CONCLUSION

Peritoneal endothelial glycocalyx was more preserved in patients treated with low-GDP, pH-neutral solution. The use of low-GDP, pH-neutral solutions could help to protect peritoneal vascular structures and functions.

C1 inhibitor mitigates peritoneal injury in zymosan-induced peritonitis

Peritonitis, due to a fungal or bacterial infection, leads to injury of the peritoneal lining and thereby forms a hazard for the long-term success of peritoneal dialysis (PD) and remains a lethal complication in patients with PD. This study investigated whether C1 inhibitor (C1-INH) could protect against the progression of peritoneal injuries with five daily administrations of zymosan after mechanical scraping of the rat peritoneum to mimic fungal peritonitis. Severe peritoneal injuries were seen in this model, accompanied by fibrinogen/fibrin exudation and peritoneal deposition of complement activation products such as activated C3 and C5b-9. However, intraperitoneal injection of C1-INH decreased peritoneal depositions of activated C3 and C5b-9, ameliorated peritoneal thickening, reduced the influx of inflammatory cells, and prevented the production of peritoneal fibrous layers with both one and two doses of C1-INH each day. Our results suggest that C1-INH might be useful to protect against peritoneal injuries after causes of peritonitis such as fungal infection. This clinically available agent may thus help extend the duration of PD.NEW & NOTEWORTHY Peritoneal injuries associated with peritonitis comprise an important issue to prevent long-term peritoneal dialysis (PD) therapy. Here, we showed that C1 inhibitor (C1-INH), as an anticomplement agent, protected against peritoneal injuries in a peritonitis animal model related to fungal infection. Therefore, C1-INH might be useful to protect against peritoneal injuries after peritonitis due to fungal infection. This clinically available agent may thus help extend the duration of PD.

[Clinical characteristics and treatment outcomes of first peritonitis in patients receiving long-term peritoneal dialysis: a multicenter study]

OBJECTIVE

To analyze the clinical characteristics and treatment outcomes of the first episode of peritoneal dialysis-associated peritonitis (PDAP) in patients receiving long-term peritoneal dialysis.

METHODS

The clinical data of patients with the first episode of PDAP in 4 general hospitals in Jilin Province from 2013 to 2019 were collected retrospectively. According to the duration of dialysis, the patients were divided into long-term (≥36 months) and short-term (< 36 months) dialysis groups for comparison of the clinical data, treatment outcomes and long-term prognostic events.

RESULTS

A total of 625 patients with PDAP were enrolled, including 93 on long-term and 532 on short-term dialysis. Compared with those on short-term dialysis, the patients on long-term dialysis had significantly higher hemoglobin levels and lower glomerular filtration rates when the first episode of PDAP occurred (P < 0.05), were more susceptible to gram-negative bacterial infections (P < 0.05), and had significantly lower initial treatment response rate (P=0.009) and complete cure rate (P=0.018) and higher extubation rate (P=0.017). Multivariate logistic regression analysis showed that in patients on long-term dialysis, the risks of extubation and treatment failure for the first episode of PDAP were 3.05 times (OR: 3.05, 95%CI: 1.35-6.91, P=0.008) and 2.81 times (OR: 2.81, 95%CI: 1.45-5.44, P=0.002) those in patients with short-term dialysis, respectively. Fungal infection (OR: 45.40, 95%CI: 1.488-1385.5, P=0.029) and mixed bacterial infection (OR: 16.50, 95%CI: 1.106-246.123, P=0.042) were independent risk factors for treatment failure of the first episode of PDAP in patients on long-term dialysis. Maintenance peritoneal dialysis, technical failure, or all-cause mortality did not differ significantly between the two groups. Multivariate Cox regression analysis suggested that long-term dialysis was not an independent risk factor for technical failure (OR: 1.36, 95%CI: 0.84-2.19, P=0.206) or all-cause mortality (OR: 1.51, 95%CI: 0.97-2.35, P=0.068) in patients with PDAP.

CONCLUSIONS

Compared with those on short-term dialysis, patients on long-term dialysis are prone to gram-negative bacterial infection when the first episode of PDAP occurs with worse treatment outcomes but similar long-term outcomes. Long-term dialysis is an independent risk factor of extubation and treatment failure for the first episode of PDAP, and fungal and mixed bacterial infections are independent risk factors for treatment failure of the first PDAP in patients with long-term dialysis.

Metal cations promote α-dicarbonyl formation in glucose-containing peritoneal dialysis fluids

Heat sterilization of peritoneal dialysis fluids (PDFs) leads to the formation of glucose degradation products (GDPs), which impair long-term peritoneal dialysis. The current study investigated the effects of metal ions, which occur as trace impurities in the fluids, on the formation of six major α-dicarbonyl GDPs, namely glucosone, glyoxal, methylglyoxal, 3-deoxyglucosone, 3-deoxygalactosone, and 3,4-dideoxyglucosone-3-ene. The chelation of metal ions by 2-[bis[2-[bis(carboxymethyl)amino]ethyl]amino]acetic acid (DTPA) during sterilization significantly decreased the total GDP content (585 μM vs. 672 μM), mainly due to the decrease of the glucose-oxidation products glucosone (14 μM vs. 61 μM) and glyoxal (3 μM vs. 11 μM), but also of methylglyoxal (14 μM vs. 31 μM). The glucose-dehydration products 3-deoxyglucosone, 3-deoxygalactosone, and 3,4-dideoxyglucosone-3-ene were not significantly affected by chelation of metal ions. Additionally, PDFs were spiked with eleven different metal ions, which were detected as traces in commercial PDFs, to investigate their influence on GDP formation during heat sterilization. Iron(II), manganese(II), and chromium(III) had the highest impact increasing the formation of glucosone (1.2–1.5 fold increase) and glyoxal (1.3–1.5 fold increase). Nickel(II) and vanadium(III) further promoted the formation of glyoxal (1.3 fold increase). The increase of the pH value of the PDFs from pH 5.5 to a physiological pH of 7.5 resulted in a decreased formation of total GDPs (672 μM vs 637 μM). These results indicate that the adjustment of metal ions and the pH value may be a strategy to further decrease the content of GDPs in PDFs.

Effect of lactate as a peritoneal dialysis fluid buffer on rat peritoneal mesothelial cells

Background

Neutral, low-glucose degradation product (GDP) peritoneal dialysis fluid (PDF) is less damaging to the peritoneum than conventional PDF but is still insufficient for biocompatibility. One remaining issue is the problem of buffering.

Methods

Using cultured rat peritoneal mesothelial cells (PMCs), the present study examined the difference between the effects of neutral low-GDP lactate PDF and neutral low-GDP bicarbonate/lactate PDF on cells. The effects of lactate stimulation on these cells were also examined.

Results

Lactate PDF enhanced mRNA expressions of α-smooth muscle actin (αSMA) and type 1 and type 3 collagens and lowered expression of e-cadherin mRNA in PMCs compared to bicarbonate/lactate PDF. Lactate stimulation increased mRNA expressions of αSMA, matrix metalloproteinase 2 (MMP2), and basic fibroblast growth factor (bFGF) and suppressed e-cadherin mRNA expression. Transforming growth factor (TGF)-β1 and TGF-β2 and collagen type 1 and 3 mRNA expressions were also enhanced by lactate stimulation.

Conclusions

These results suggest that lactate as a PDF buffer may act on PMCs to promote epithelial-mesenchymal transition (EMT) and production of TGF-β, bFGF, and collagen.

Comparison between standard single chamber versus dual chamber low glucose degradation product peritoneal dialysis fluids

Dual chamber (DC) peritoneal dialysis (PD) dialysates contain fewer glucose degradation products (GDPs), so potentially reducing advanced glycosylation end products (AGEs), which have been reported to increase inflammation and cardiovascular risk. We wished to determine whether use of DC dialysates resulted in demonstrable patient benefits. Biochemical profiles, body composition, muscle strength, and skin autofluorescence measurements of tissue AGEs (SAF) were compared in patients using DC and standard single chamber dialysates. We studied 263 prevalent PD patients from 2 units, 62.4% male, mean age 61.8 ± 16.1 years, 78 (29.7%) used DC dialysates. DC patients were younger (55.9 ± 16.4 vs. 64.2 ± 15.4 years), and more had lower Davies comorbidity score (median 1 (0-1) vs. 1 (0, 2)), slower peritoneal transport (D/P creatinine 0.67 ± 0.12 vs. 0.73 ± 0.13), greater extracellular water-to-total body water (ECW/TBW) ratio (0.46 ± 0.05 vs. 0.42 ± 0.06), all P < .001, whereas there were no differences in the duration of PD (median (IQR) 19 (8-32) vs. 14 (8-23) months), residual renal function (Kt/V_urea 0.71 ± 0.71 vs. 0.87 ± 0.82), urine volume (642 (175-1200) vs. 648 (300-1200) mL/day), hand grip strength (26.9 ± 10.5 vs. 24.9 ± 10.7 kg), C-reactive protein (4(1-10) vs. 4(2-12) mg/L), and SAF (median 3.60 (3.02, 4.40) vs. 3.50 (3.00, 4.23)) AU. In our cross-sectional observational study, we were not able to show a demonstrable advantage for using low GDP dialysates over conventional glucose dialysates, in terms of biochemical profiles, residual renal function, muscle strength, or tissue AGE deposition. More patients using low GDP dialysates were slower peritoneal transporters with higher ECW/TBW ratios.

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.

Blood pressure and volume management in dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Blood pressure (BP) and volume control are critical components of dialysis care and have substantial impacts on patient symptoms, quality of life, and cardiovascular complications. Yet, developing consensus best practices for BP and volume control have been challenging, given the absence of objective measures of extracellular volume status and the lack of high-quality evidence for many therapeutic interventions. In February of 2019, Kidney Disease: Improving Global Outcomes (KDIGO) held a Controversies Conference titled Blood Pressure and Volume Management in Dialysis to assess the current state of knowledge related to BP and volume management and identify opportunities to improve clinical and patient-reported outcomes among individuals receiving maintenance dialysis. Four major topics were addressed: BP measurement, BP targets, and pharmacologic management of suboptimal BP; dialysis prescriptions as they relate to BP and volume; extracellular volume assessment and management with a focus on technology-based solutions; and volume-related patient symptoms and experiences. The overarching theme resulting from presentations and discussions was that managing BP and volume in dialysis involves weighing multiple clinical factors and risk considerations as well as patient lifestyle and preferences, all within a narrow therapeutic window for avoiding acute or chronic volume-related complications. Striking this challenging balance requires individualizing the dialysis prescription by incorporating comorbid health conditions, treatment hemodynamic patterns, clinical judgment, and patient preferences into decision-making, all within local resource constraints.