Episodes Of Peritonitis Research Articles

#5199 ULTRASOUND EXAMINATION OF THE SUBCUTANEOUS PERITONEAL CATHETER TUNNEL IN CASES NOT RELATED TO INFECTION

Abstract Background and Aims According to the guidelines of the International Society of Peritoneal Dialysis possible indications of ultrasound (US) examination of the catheter tunnel are suspected tunnel infection, initial evaluation of exit-site infection without clinical signs of tunnel involvement, follow-up of exit-site and tunnel infection after treatment and relapsing peritonitis episodes. Other authors suggest US examination of the subcutaneous tunnel in every case of peritonitis. We analyzed the associations between US findings at the catheter tunnel and their clinical impact, exclusively in cases not related to catheter infection. Method The subcutaneous tunnel of the peritoneal catheter was examined with a linear probe of 6.5-10 MHz having covered the exit site with a transparent adhesive film-dressing. For the retrospective investigation covering the last 10 years, we selected peritoneal dialysis patients who performed an US examination without clinical signs or suspect of exit site or tunnel infection. During the US examination, the distance of the external cuff from the exit site, the presence and extend of leakage or size of a hematoma (along the catheter and at the surgical site), the proximity of the inferior epigastric artery to the catheter, the configuration of the subcutaneous tunnel (including inclination and direction of the catheter at the entrance into the peritoneal cavity) and the position of the inner catheter cuff were documented. Results Several US findings were found to be associated to a specific risk or need of intervention in the follow up of the patient. The following table reassumes the US findings and the respective clinical impact. Conclusion US findings documented during the examination of the catheter tunnel in cases not related to infection have a certain clinical impact due to their association to a specific risk or need of intervention, and therefore should not be overseen during the examination.

#4850 20 YEARS' EXPERIENCE OF PERITONEAL DIALYSIS IN SARAWAK, MALAYSIA

Abstract Background and Aims Peritoneal dialysis is a modality of renal replacement therapy first introduced in the 1960s. In the event of the recent COVID 19 pandemic, peritoneal dialysis is gaining popularity due to the increased preference of home dialysis. Sarawak is the largest state in Malaysia with a population of more than 2 million. Unfortunately, 13% of households in the state are living in poverty. We present our experience with continuous ambulatory peritoneal dialysis (CAPD) for the past years in a geographically and socioeconomically challenging region. Method Sarawak General Hospital is the centre of referral for Tenckhoff catheter insertion from other districts in Sarawak. This is a retrospective record review of all CAPD patients who were under our clinic follow up from 2001 to 2022. Data examined included patient's demographic data, incidence of peritoneal dialysis related peritonitis and their outcome. Results All of the patients on CAPD were recorded by December of each year since we started our service in 2001 which shows a rising trend of patients on CAPD, with the highest in December 2022 at 399 patients. The number of patients with dialysis related peritonitis was also collected. Despite having more patients on CAPD, the number of peritonitis episodes per patient-year were in a decreasing trend. This was the result of the implementation of empirical first line intra-peritoneal antibiotics as part of the CAPD Peritonitis Management Protocol in 2015 and Decontamination Protocol in 2016. Conclusion Despite the headwinds of geographic and socioeconomic challenges, the number of patients on CAPD is on the rise. Over the years, peritonitis rate declined approaching to 0.2 episodes per patient-year. This was made possible with the introduction of local decontamination protocol and CAPD peritonitis management protocol, which helped improve the life expectancy and health of renal patients in the region.

#5462 METABOLIC PROFILING IN CHILDREN WITH END STAGE RENAL DISEASE ON PERITONEAL DIALYSIS: PRELIMINARY RESULTS OF AN ONGOING PRESPECTIVE STUDY

Abstract Background and Aims Peritoneal dialysis (PD) is the main renal replacement treatment for children and adolescents with end stage kidney disease (ESRD). Peritoneal fibrosis is a major complication in long-term PD patients. Aim of the present study is to record the metabolic "fingerprint" of children on PD and to investigate its correlation with PD history and dialysis adequacy as well as the emergence of potential biomarkers that could detect early or predict peritoneal dysfunction. Method Serum samples from 15 patients undergoing peritoneal dialysis were analyzed. Two targeted LC-MS methodologies were used for the determination of 107 metabolites in total. The obtained results were compared based on demographic and clinical parameters, both before and after the dialysis procedure. Serum samples were further divided into subgroups, based on PD duration, creatine clearance, sex, anuria. Reragding metabolic techologies used, all samples were analyzed by a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS / MS) method previously developed and validated in our laboratory for the simultaneous determination of amino acids and their derivatives in biological fluids. Αlso, high flow analysis was carried out (LC-qTOF analysis – HPLC /MS). Results 8-OH-2-deoxyguanosine (8-hydroxy-2' -deoxyguanosine (8-OHdG) was the only metabolite found to differentiate between serum samples collected before and after PD (p<0.05). Grouping the samples by age groups (child, teen and late teen-young adult) we found out that succinate like lactate, N-acetyl-β-d-glucosaminidase (NAG), are potential markers for the quality of PD. Grouping the patients by number of peritonitis episodes (3 groups: no episodes, 1-2 episodes and >3 episodes) cytosine, riboflavin, glutamic acid, methylxantine and malate found to differentiate between the three groups (p <0.05). Regrading the creatinine cleranace, xylose, dCDP, HIAA, pyroglutamic, A CoA and methylxantine seems to be significan biomarkers. Grouping the patients based on the presence or absence of diuresis,HIAA, kynurenic,glucuronic and pantothenic acid found to differentiate between the two groups (p<0.05) Conclusion Based on the literatute the majority of the metabolites showed a statistically significant difference are involved in the inflammation process. Our results are the preliminary results of an ongoing prospective study. Limitation of the study, is the small sample of patients, which does not allow safe clinical interpretation. In any case, metabolomics seems to be a useful tool for the study and identification of biomarkers in patients with ESRD on PD.

#4387 LIQUID BIOPSY IN PATIENTS TREATED WITH BIOCOMPATIBLE PERITONEAL DIALYSIS FLUIDS – ITS RELATIONSHIP WITH CYTOLOGICAL AND HISTOLOGICAL FINDINGS

Abstract Background and Aims Peritoneal fibrosis can limit long term peritoneal membrane function in peritoneal dialysis (PD) patients. It has been related to bioincompatible PD fluids and peritoneal infections. There are no prospective studies regarding correlation between effluent biomarkers and peritoneal biopsy findings. Our aim was to study the possible relation of peritoneal effluent biomarkers and peritoneal morphology alterations. Method Multicenter prospective study in a cohort of stable PD patients treated with biocompatible PD fluids who received a kidney transplant. We collected in each patient peritoneal biopsy samples and peritoneal effluent fluid. We analyzed the relation between effluent biomarkers, phenotype of mesothelial cells (MC) cultured ex vivo, and peritoneal biopsy parameters (mesothelial integrity, fibrosis and hyalinizing vasculopathy). We compared them with patient characteristics, including peritoneal transport parameters. The biomarkers tested were Collagen-1 (COL-1), Fibronectin (FN), Collagen-13 (COL-13), Interleukin-6 (IL-6), Trombospondin-1, Cadherin 13 (CDH-13), CA-125, Gremlin-1 (GREM-1), Matrix metalloproteinase 2 (MMP-2), CC chemokine ligand 18 (CCL18), Plasminogen activator inhibitor 1 (PAI-1) and Vascular endothelial growth factor A (VEGF-A). Results Forty patients were included (mean age 54.5±15 years, 64% male, 24.1% diabetics). Mean time on PD was 25.5±27 months, 62.1% were on automated PD (APD) and 17.2% had prior peritonitis episodes. A normal MC culture phenotype was observed in 78% of patients. In peritoneal biopsies samples we found partial or total mesothelium preservation in 39%, submesothelial thickness in 42% and vasculopathy in 14% of cases. Effluent PAI-1 levels were significantly lower in patients with mesothelial cell loss than in those with mesothelial preservation (21.62 vs. 38.59 pg/ml respectively; p = 0.031). Patients with peritoneal fibrosis showed significantly higher effluent CDH-13 levels (3.51 vs. 2.32 pg/ml; p = 0.048) and supernatant PAI-1 levels (1183 vs. 72.73; p = 0.000) than those without fibrosis. No other statistical differences were found in other biomarkers analysed. Conclusion Most patients treated with biocompatible peritoneal dialysis fluids showed normal mesothelial cell phenotype in peritoneal effluent culture. Lower PAI-1 effluent levels were associated with mesothelial cell loss and higher effluent CDH-13 levels were related to peritoneal fibrosis.

#4673 POLY(I:C) INDUCES MORPHOLOGICAL CHANGES AND TYPE I INTERFERON-MEDIATED INFLAMMATORY RESPONSE IN MESOTHELIAL CELLS FROM PERITONEUM

Abstract Background and Aims Peritonitis is a major cause of morbidity and discontinuation of the therapy in peritoneal dialysis (PD) patients. Most of peritonitis episodes during PD may be imputed to bacterial infection, although in about 20% of the cases a viral origin may be hypothesized. Toll-like receptors (TLRs) play a critical role in innate immune responses by specifically recognizing molecular patterns from different microorganisms, including bacteria, fungi, and viruses. Polyinosinic:polycytidylic acid (Poly(I:C)) is a synthetic analogue of double-stranded RNA (dsRNA) that mimics the anti-viral immune response by activating TLR3. Upon activation, TLR3 signaling pathway leads to the induction of NF-ΚB pathway and the interferon response (IRF3 activation). The aim of this work is to study the ex vivo and in vivo effect of Poly(I:C) treatment in primary human mesothelial cells (MCs) and mice peritoneum. Methods MCs were collected from effluent fluids of 8 clinically stable PD patients and amplified for ex vivo experiments. MCs were treated with Poly(I:C) (2 ng/μl) or TGFβ1 (2 ng/ml). After 48 hours of stimulation, samples were collected for RNA subsequent analysis. Poly(I:C) was intraperitoneally delivered to mice daily for 10 days, using two different doses: 30 mg/kg (n = 6) and 90 mg/kg (n = 4) of weight. Non-treated mice were used as control (n = 6). Mice were euthanized and peritoneal tissue was collected for the subsequent RNA, protein, and histological experiments. Gene expression analyses of TLRs, interferon-stimulated genes (ISGs), and other inflammatory markers were performed by qPCR. Protein analysis from cell lysates was performed by western blot and cytokine and chemokine levels from cell supernatants were detected by ELISA assay. Results MCs from PD patients expressed a specific subset of TLRs, which were modulated by stimulation with Poly(I:C), being TLR3 the most induced receptor. Additionally, Poly(I:C) induced a bona fide mesothelial to mesenchymal transition (MMT), characterized by the acquisition of a spindle-like morphology, increased expression of mesenchymal markers such as SNAIL, TGFB1, FN1, MMP9, and MMP14, and decreased expression of the epithelial markers ECAD and CALB2. Moreover, Poly(I:C) increased mRNA and protein levels of several cytokines and chemokines, such as TNFα, IL-6, IL-1β, IFNβ, CXCL8, and CXCL9; and ISGs, including CXCL10, MX1, IFIT1, and IFITM1. In vivo, Poly(I:C) administration in mice induced peritoneal inflammation, characterized by increased gene expression of proinflammatory response-related factors, including Ccl5, Arg1, and the ISGs Cxcl10 and Ifit1, in a dose-dependent manner. Conclusion Treatment with Poly(I:C) is sufficient to induce a profibrotic/proinflammatory response in MCs in ex vivo and in vivo settings. These discoveries highlight the role of viral infections in peritoneum damage and may provide insight for further studies aimed at specifically counteracting the effect of viral infections in peritonitis in PD patients.

Laparoscopic peritoneal dialysis catheter insertion: an oasis harnessed-experience and results at a tertiary care centre in India.

Peritoneal dialysis is a life sustaining renal replacement therapy for patients with end stage renal disease. In comparison to hemodialysis it offers better mobility and independence to patients. A number of techniques including open, laparoscopic and fluoroscopy guided, and their modifications, have been described for intraperitoneal catheter insertion. We describe our technique and results of laparoscopic peritoneal dialysis (PD) catheter insertion at a tertiary care centre in India. 48 patients were referred from the department of nephrology at our centre for laparoscopic PD catheter insertion. A two port technique was used in 37 patients and three port technique was implemented in the rest for simultaneous adhesiolysis and/or omentectomy. A straight tip catheter was tunneled through the rectus muscle in all patients. Two patients had incisional hernia from a previous abdominal surgery which was repaired concomitantly with onlay meshplasty. The operative time ranged between 20 and 35min under general anaesthesia. Three patients were subjected to urgent start dialysis of which one patient developed peridrain leak as an early complication which was managed conservatively. All other patients were commenced on peritoneal dialysis two weeks after surgery. There was no other surgical site occurrence or episodes of peritonitis reported in a 6month follow up period with the department of nephrology. In the era of minimal access surgery, the laparoscopic approach is feasible for widespread and safe use for PD catheter insertion. The benefits of PD can thus be made available to patients at civil hospitals even with a basic laparoscopy setup.

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.

INCIDENCE, CLINICAL OUTCOME AND CHANGES OF PERITONEAL MEMBRANE TRANSPORT STATUS IN TREATED CONTINUOUS AMBULATORY PERITONEAL DIALYSIS (CAPD) RELATED PERITONITIS

Peritoneal dialysis-related peritonitis remains the most common complication and a key barrier to peritoneal dialysis’ long-term success. The present study aimed to report on the incidence of peritonitis and clinical outcomes in CKD patients on CAPD at a hospital in Vietnam’s south and evaluate the peritoneal membrane transport status before and after peritonitis therapy. This study was a cross-sectional study involving 141 participants sampled from the warded adult patients at An Giang center general hospital, in Vietnam. Peritonitis rate was measured in terms of incidences per patient-year. Dialysis fluid was drawn under aseptic conditions and treated using a culture approach to identify bacteria. The response treatment time for each episode of peritonitis after receiving empirical antibiotic medication. We use Peritoneal Equilibration Test (PET) to determine the peritoneal transport status. Peritonitis was found in 29.8% of the cases. The number of episodes of peritonitis per patient-year was 0.035. Negative bacteria account for 81.0 percent of all cases tested. It took an average of 3 to 5 days for a clinical response. Before and after peritonitis, there was no statistically significant connection between transport status groups. The rate of peritonitis identified in this study was significantly lower than that recommended by the International Society for Peritoneal Dialysis (ISPD) recommendations. More research is needed to fully understand the variables that influence the clinical outcomes of peritonitis and the remaining function of the peritoneal membrane.

Survival outcomes of HIV-positive adults on peritoneal dialysis at Helen Joseph renal unit.

HIV is a risk factor for the development of chronic kidney disease. People with chronic kidney disease in the state sector are likely to be prescribed continuous ambulatory peritoneal dialysis (CAPD). Previous studies have raised concern about the safety of CAPD in people living with HIV (PLWH) compared to HIV-negative patients. To compare the risk of peritonitis, and modality and patient survival by HIV status in patients receiving CAPD at Helen Joseph Hospital. A retrospective study of patients receiving CAPD between 01 January 2007 and 31 December 2017 was undertaken. Five-year patient and modality survival were modelled for PLWH and HIV-negative subgroups and analysed using the log-rank test; the effect of CD4 count, HIV viral load, and duration of antiretroviral therapy on these parameters in PLWH were additionally modelled using the Cox Proportional Hazards technique. Eighty-four patients, comprising of 21 PLWH and 63 HIV-negative patients, were analysed. No difference was observed in the proportion of patients who had at least one episode of peritonitis between PLWH (61.2%) and HIV-negative patients (63.5%) (P = 0.547). A trend towards increased risk of peritonitis due to Gram-negative organisms in PLWH was noted (odds ratio: 3.20, 95% confidence interval: 0.86-11.9, P = 0.083). No difference was observed in 5-year patient or modality survival on CAPD between PLWH (log-rank P = 0.161) and HIV-negative patients (log-rank P = 0.240). People living with HIV should not be excluded from CAPD as a mode of kidney replacement therapy (KRT).

Multidrug-resistant organism-peritoneal dialysis associated peritonitis: clinical and microbiological features and risk factors of treatment failure.

Multidrug-resistant (MDR) bacterial infection causes difficulty in the therapy of peritoneal dialysis-associated peritonitis (PDAP); however, there are few studies on multidrug-resistant organism (MDRO)-PDAP. In view of growing concerns about MDRO-PDAP, the aim of this study was to investigate the clinical features, risk factors of treatment failure, and causative pathogens of MDRO-PDAP. In total, 318 patients who underwent PD between 2013 and 2019 were included in this multicenter retrospective study. Clinical features, patient outcomes, factors related to treatment failure, and microbiological profiles associated with MDRO-PDAP were analyzed and risk factors for treatment failure associated with MDR-Escherichia coli (E. coli) were further discussed. Of 1,155 peritonitis episodes, 146 eligible episodes of MDRO-PDAP, which occurred in 87 patients, were screened. There was no significant difference in the composition ratio of MDRO-PDAP between 2013-2016 and 2017-2019 (p > 0.05). E. coli was the most prevalent MDRO-PDAP isolate, with high sensitivity to meropenem (96.0%) and piperacillin/tazobactam (89.1%). Staphylococcus aureus was the second most common isolate and was susceptible to vancomycin (100%) and linezolid (100%). Compared to non-multidrug-resistant organism-PDAP, MDRO-PDAP was associated with a lower cure rate (66.4% vs. 85.5%), higher relapse rate (16.4% vs. 8.0%), and higher treatment failure rate (17.1% vs.6.5%). Dialysis age [odds ratio (OR): 1.034, 95% confidence interval (CI): 1.016-1.052, p < 0.001] and >2 previous peritonitis episodes (OR: 3.400, 95% CI: 1.014-11.400, p = 0.047) were independently associated with treatment failure. Furthermore, longer dialysis age (OR: 1.033, 95% CI: 1.003-1.064, p = 0.031) and lower blood albumin level (OR: 0.834, 95% CI: 0.700-0.993, p = 0.041) increased the risk of therapeutic failure for MDR-E. coli infection. The proportion of MDRO-PDAP has remained high in recent years. MDRO infection is more likely to result in worse outcomes. Dialysis age and previous multiple peritonitis infections were significantly associated with treatment failure. Treatment should be promptly individualized based on local empirical antibiotic and drug sensitivity analyses.

Weight loss and weight gains in patients starting peritoneal dialysis; the effect of peritonitis.

Earlier studies reported that peritoneal dialysis (PD) patients gained fat mass after initiating dialysis. Clinical practice and demographics have changed over time with earlier initiation of dialysis and increasing numbers of elderly, co-morbid patients. As such, we wished to review changes in body composition with dialysis. Changes in body composition were compared by dual x-ray absorptiometry (DXA) in 151 adult PD patients, 81 males (54.6%), 50 diabetic (30.1%), mean age 60.5 ± 16.7 years, shortly after starting PD and then a median of 24 months later, to allow for the initial impact of dialysis. Overall, weight appeared stable (71.7 ± 15.4 vs. 71.9 ± 15.3 kg). On follow-up, total weekly urea clearance fell from 2.29 (1.85-3.0) to 1.93 (1.63-2.4) whereas peritoneal glucose absorption increased from 119 (46-217) to 321 (187-805) mmol/day, p < .001, and estimated dietary protein (nPNA) fell from 0.92 ± 0.23 to 0.86 ± 0.23 g/kg/day, p = .006. However, 69 (45.7%) patients gained weight, with greater change in both lean and fat mass index versus those with weight loss (0.8 [-0.5 to 2.0] vs. -0.7 [-2.1 to 0.2] and 0.9 [-0.1 to 2.3] vs. 0 [-2.6 to 0.8] kg/m2 , p < .001), respectively. Although there were no differences in hospital admissions, patients who gained weight experienced fewer episodes of PD peritonitis (0 [0-1] vs. 1[0-2], p = .019). Dietary protein intake declined over time, and more PD patients lost weight. The major difference between those who gained and lost weight was episodes of peritonitis. Greater attention to nutritional support may potentially reduce loss of lean body mass.

Clinical Characteristics of Enterococcus-Associated Peritonitis in Patients with Peritoneal Dialysis.

This study aims to investigate the clinical characteristics of enterococcus-associated peritonitis in patients with peritoneal dialysis (PD). In this retrospective study, patients with PD-associated enterococcal peritonitis (Group E) who were treated in our center between January 2010 and September 2020 were included. Patients with PD-associated streptococcus peritonitis (Group S) and patients with coagulase-negative staphylococcus peritonitis (Group CNS) were matched 1:1 as cohort-control groups. The clinical characteristics and prognosis of these patients were analyzed. A total of 21 peritonitis episodes were noted in nine males and nine females, with an average age of 60.33±14.79 years and an average dialysis duration of 63.56±35.23 months. Mixed infection was observed in 7 out of 21 cases. A total of 22 strains of enterococci were identified in bacterial culture, all sensitive to vancomycin. There were significant differences in white blood cell (WBC) count and blood urea nitrogen (BUN) level among three groups on admission (p<0.05). In all three groups, WBC count on the second and third day post-treatment was higher in Group E than in other groups (p<0.05). The cure rate in Group E was lower than in other groups (p<0.01). The mortality rate in Group E was slightly higher than in other groups (p>0.05). Kaplan-Meier analysis revealed a significant difference in the cumulative survival among three groups (p<0.05). Enterococcus peritonitis is a rare and severe complication of peritoneal dialysis. Although vancomycin is effective for the treatment of Enterococcus infection, Enterococcus peritonitis still has a high rate of treatment failure, poor response to treatment, and poor prognosis as compared to CNS and streptococcus-related infections.

Hospital-acquired peritonitis in patients on peritoneal dialysis: A call to action.

Peritonitis remains a significant complication of peritoneal dialysis (PD), and severe episodes of peritonitis lead to structural and functional alterations of the peritoneal membrane, which can result in a permanent transfer to hemodialysis. Although PD is designed primarily to be delivered in the community setting, patients on PD get hospitalized for a number of reasons. In this commentary, we highlight the enormous risks each hospitalization has on the occurrence of peritonitis in patients on PD and the need to understand factors that predispose patients to hospital-acquired peritonitis. Furthermore, we suggest directions on several strategies that could not only reduce the risks of developing peritonitis but also improve outcomes of patients on PD who get hospitalized for an unrelated illness.

Low immunoglobulin G concentrations are not associated with an increased risk of peritoneal dialysis-related peritonitis.

Peritonitis is a common and severe complication of peritoneal dialysis (PD) and is associated with high morbidity and sometimes also with mortality. Identification of risk factors, as well as protective mechanisms for peritonitis, is important to reduce peritonitis-induced morbidity. According to the current literature, IgG concentrations might be associated with peritonitis in PD-treated patients. In this study, we aimed to investigate possible associations between dialysate or serum IgG concentration and peritonitis risk in a longitudinal cohort of PD-treated patients. We analyzed prospectively collected data obtained during the first standard peritoneal permeability analysis (SPA), performed in incident PD patients, aged >18 years who started PD treatment in our tertiary-care university hospital from January 1, 1994 until December 31, 2008. Patients were divided in groups according to dialysate or serum IgG concentrations and according to peritonitis incidence. A possible association between low dialysate or serum IgG concentrations and time to the first peritonitis episode was investigated using cox proportional hazard models. 120 patients were included in our analyses with a median follow-up time of 36 (16-92) months. No significant association between dialysate, nor serum IgG and time to peritonitis was found (HR 0.27 (95% CI 0.65-1.62), p = 0.911 and HR 0.87 (95% CI 0.70-1.68), p = 0.708, respectively). Moreover, IgG concentrations were not associated with peritonitis incidence, nor with the recurrence of peritonitis. Finally, we found no significant difference in dialysate or serum IgG concentrations between patients who remained peritonitis-free (58.0 ± 35.6 mg/L in dialysate, 11.1 ± 4.4 g/L in serum), and those who experienced a peritonitis episode during follow-up (59.5 ± 41.9 mg/L in dialysate, 10.3 ± 4.3 g/L in serum), respectively. Dialysate or serum IgG are not major determinants of local peritoneal defense against peritonitis.

Relationship between serum iPTH and peritonitis episodes in patients undergoing continuous ambulatory peritoneal dialysis.

Peritonitis is considered as one of the most serious complications that cause hospitalization in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). There is limited evidence on the impact of the parathyroid hormone (PTH) on the first peritoneal dialysis (PD)-associated peritonitis episode. We aimed to investigate the influence of serum intact parathyroid hormone (iPTH) on peritonitis in patients undergoing PD. This was a retrospective cohort study. Patients undergoing initial CAPD from a single center in China were enrolled. The baseline characteristics and clinical information were recorded. The primary outcome of interest was the occurrence of the first PD-associated peritonitis episode. Five Cox proportional hazard models were constructed in each group set. In group set 1, all participants were divided into three subgroups by tertiles of the serum concentration of iPTH; in group set 2, all participants were divided into three subgroups based on the serum concentration of iPTH with 150pg/ml interval (<150, 150-300, and >300pg/ml). Hazard ratios and 95% confidence intervals (CIs) were calculated for each model. The multivariate linear regression analysis elimination procedure assessed the association between the clinical characteristics at baseline and the iPTH levels. Restricted cubic spline models were constructed, and stratified analyses were also conducted. A total of 582 patients undergoing initial PD (40% women; mean age, 45.1±11.5years) from a single center in China were recruited. The median follow-up duration was 25.3months. Multivariate Cox regression analysis showed that, in the fully adjusted model, a higher serum iPTH level (tertile 3, iPTH>300pg/ml) was significantly associated with a higher risk of PD-associated peritonitis at 3years [tertile 3: hazard ratio (HR)=1.53, 95%CI=1.03-2.55, p=0.03; iPTH>300pg/ml: HR=1.57, 95%CI=1.08-2.27, p=0.02]. The hazard ratio for every 100pg/ml increase in serum iPTH level was 1.12 (95%CI=1.05-1.20, p<0.01) in the total cohort when treating iPTH as a continuous variable. An elevated iPTH level was significantly associated with an increased risk of peritonitis in patients undergoing CAPD.

Novel Aspects of the Immune Response Involved in the Peritoneal Damage in Chronic Kidney Disease Patients under Dialysis.

Chronic kidney disease (CKD) incidence is growing worldwide, with a significant percentage of CKD patients reaching end-stage renal disease (ESRD) and requiring kidney replacement therapies (KRT). Peritoneal dialysis (PD) is a convenient KRT presenting benefices as home therapy. In PD patients, the peritoneum is chronically exposed to PD fluids containing supraphysiologic concentrations of glucose or other osmotic agents, leading to the activation of cellular and molecular processes of damage, including inflammation and fibrosis. Importantly, peritonitis episodes enhance peritoneum inflammation status and accelerate peritoneal injury. Here, we review the role of immune cells in the damage of the peritoneal membrane (PM) by repeated exposure to PD fluids during KRT as well as by bacterial or viral infections. We also discuss the anti-inflammatory properties of current clinical treatments of CKD patients in KRT and their potential effect on preserving PM integrity. Finally, given the current importance of coronavirus disease 2019 (COVID-19) disease, we also analyze here the implications of this disease in CKD and KRT.

Characteristics and outcomes of hospital-acquired and community-acquired peritonitis in patients on peritoneal dialysis: a retrospective cohort study.

Peritonitis remains a significant complication of peritoneal dialysis. However, there is limited information on the clinical characteristics and outcomes of hospital-acquired peritonitis compared to community-acquired peritonitis in patients undergoing peritoneal dialysis. Furthermore, the microbiology and outcomes of community-acquired peritonitis may vary from hospital-acquired peritonitis. Therefore, the aim was to gather and analyse data to address this gap. Retrospective review of the medical records of all adult patients on peritoneal dialysis within the peritoneal dialysis units in four university teaching hospitals in Sydney, Australia, who developed peritonitis between January 2010 and November 2020. We compared the clinical characteristics, microbiology and outcomes of community-acquired peritonitis and hospital-acquired peritonitis. Community acquired peritonitis was defined as the development of peritonitis in the outpatient setting. Hospital-acquired peritonitis was defined as: (1) developed peritonitis anytime during hospitalisation for any medical condition other than peritonitis, (2) diagnosed with peritonitis within 7days of hospital discharge and developed symptoms of peritonitis within 3days of the hospital discharge. Overall, 904 episodes of peritoneal dialysis-associated peritonitis were identified in 472 patients, of which 84 (9.3%) episodes were hospital-acquired. Patients with hospital-acquired peritonitis had lower mean serum albumin levels compared to those with community-acquired peritonitis(22.95g/L vs. 25.76g/L, p = 0.002). At the time of diagnosis, lower median peritoneal effluent leucocyte and polymorph counts were observed with hospital-acquired peritonitis compared to community-acquired peritonitis (1236.00/mm3 vs. 3183.50/mm3, p < 0.01 and 1037.00/mm3 vs. 2800.00/mm3, p < 0.01, respectively). Higher proportions of peritonitis due to Pseudomonas spp. (9.5% vs. 3.7%, p = 0.020) and vancomycin-resistant Enterococcus (2.4% vs. 0.0%, p = 0.009), lower rates of complete cure (39.3% vs. 61.7%, p < 0.001), higher rates of refractory peritonitis (39.3% vs. 16.4%, p < 0.001) and higher all-cause mortality within 30days of peritonitis diagnosis (28.6% vs. 3.3%, p < 0.001) were observed in the hospital-acquired peritonitis group compared to the community-acquired peritonitis group, respectively. Despite having lower peritoneal dialysis effluent leucocyte counts at the time of diagnosis, patients with hospital-acquired peritonitis had poorer outcomes, including lower rates of complete cure, higher rates of refractory peritonitis and higher rates of all-cause mortality within 30days of diagnosis, compared to those with community-acquired peritonitis.

Calculated inflammatory markers derived from complete blood count results, along with routine laboratory and clinical data, predict treatment failure of acute peritonitis in chronic peritoneal dialysis patients

Background & Aims Complete blood count (CBC)-derived inflammatory markers are predictive biomarkers for the prognosis of many diseases. However, there was no study on patients with peritoneal dialysis-associated peritonitis (PDAP). We aimed to investigate the value of these markers in predicting treatment failure of acute peritonitis in chronic PD patients. Methods The records of 138 peritonitis episodes were reviewed and divided into treatment success or failure groups in a single center for 10 years. CBC-derived markers and other routine data were recorded before peritonitis treatment was initiated. Univariate and multivariate regression analyses and the receiver operating characteristic (ROC) curve about the predictors of treatment outcomes were performed. Results Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), and derived NLR were significantly higher in the failure group. Univariate logistic regression results showed that NLR and PLR were risk factors of treatment outcomes. The backward stepwise multivariate logistic regression results demonstrated that NLR [adjusted odds ratio (aOR), 1.376; 95% confidence intervals (CI), 1.105–1.713; p = .004], PLR (aOR, 1.010; 95%CI, 1.004–1.017; p = .002) were risk factors, but hemoglobin-to-lymphocyte ratio (HLR) (aOR, 0.977; 95%CI, 0.963–0.991; p = .001), and SII (aOR, 0.999; 95%CI, 0.998–1.000; p = .040) were protective factors. A combination of age, PD vintage, Gram-positive peritonitis, staphylococcus aureus, culture-negative, NLR, PLR, HLR, and SII would improve prognostic performance. The area under this ROC curve was 0.85, higher than other factors. Conclusions NLR, PLR, HLR, and SII were associated with PDAP outcomes. Age, PD vintage, NLR, and PLR were significant risk factors in PDAP patients.

Differentiation of Spontaneous Bacterial Peritonitis from Secondary Peritonitis in Patients with Liver Cirrhosis: Retrospective Multicentre Study

Ascitic fluid infection is a serious complication of liver cirrhosis. The distinction between the more common spontaneous bacterial peritonitis (SBP) and the less common secondary peritonitis in patients with liver cirrhosis is crucial due to the varying treatment approaches. This retrospective multicentre study was conducted in three German hospitals and analysed 532 SBP episodes and 37 secondary peritonitis episodes. Overall, >30 clinical, microbiological, and laboratory parameters were evaluated to identify key differentiation criteria. Microbiological characteristics in ascites followed by severity of illness and clinicopathological parameters in ascites were the most important predictors identified by a random forest model to distinguish between SBP and secondary peritonitis. To establish a point-score model, a least absolute shrinkage and selection operator (LASSO) regression model selected the ten most promising discriminatory features. By aiming at a sensitivity of 95% either to rule out or rule in SBP episodes, two cut-off scores were defined, dividing patients with infected ascites into a low-risk (score ≥ 45) and high-risk group (score < 25) for secondary peritonitis. Overall, the discrimination of secondary peritonitis from SBP remains challenging. Our univariable analyses, random forest model, and LASSO point score may help clinicians with the crucial differentiation between SBP and secondary peritonitis.

Catheter insertion techniques for improving catheter function and clinical outcomes in peritoneal dialysis patients.

Catheter insertion techniques for improving catheter function and clinical outcomes in peritoneal dialysis patients.