Episodes Of Peritonitis Research Articles

A predictive model of treatment effectiveness of refractory peritoneal dialysis-related peritonitis in patients with peritoneal dialysis: a single-center observational study in South China

Abstract Background To prevent loss of peritoneal function caused by persistent abdominal inflammation, the guidelines recommend early extubation in patients with refractory peritoneal dialysis-associated peritonitis (rPDAP). In attempt to pinpoint high-risk patient cohorts that did not respond to treatment for refractory peritonitis, we created a model to predict the effectiveness of peritonitis treatment. Methods This observational cohort study included peritoneal dialysis (PD) patients from January 1, 2011 to December 31, 2020. Multivariate logistic regression analysis was used to explore the factors affecting the occurrence and prognosis of rPDAP, and to construct a predictive model for the success of rPDAP treatment. Receiver operator characteristic (ROC) curve, calibration and decision curve were drawn to evaluate the predictive performance of the model. Results A total of 1, 397 cases of peritoneal dialysis-associated peritonitis (PDAP) occurred in our center during the study period, of which 558 cases were diagnosed as rPDAP. The incidence of refractory peritonitis was 0.047 cases/patient-year. In the study, 440 cases with rPDAP were included. Among them 304 cases (69.1%) had been successfully cured, while 136 cases (30.9%) were treatment failure, of which 19 cases (4.3%) died, 85 (19.3%) cases transferred to hemodialysis and 32 cases (7.2%) were relapse/recurrent peritonitis. Dialysate culture results showed 132 (30.0%) cases were infected with gram positive bacteria, 161 (36.6%) gram negative bacteria. Multivariate Logistic regression analysis showed that episodes of peritonitis previously ≤ 3 times were correlated with the better prognosis of rPDAP, but white blood cell (WBC) counts in peritoneal dialysate on the 3rd day of peritonitis or WBC counts on the 5th day ≥ 300 × 106/L, the pathogenic microorganism with gram-negative bacteria, as well as longer duration of PD were associated with poor outcomes. The C-statistical value of the training data set was 0.870 (95%CI: 0.821–0.918). The calibration curve and clinical decision-making curve also proved that this nomogram could accurately predict the success of treatment in patients with refractory peritonitis. Conclusion The nomogram model created through internal verification indicated a strong clinical application value and a high prognostic prediction accuracy for rPDAP.

Clinical outcomes in peritoneal dialysis with refractory peritonitis: significance of the day 5 cell count.

Peritoneal dialysis-associated peritonitis is a common and severe complication of peritoneal dialysis, associated with high morbidity and mortality. However, there's a lack of research on refractory peritonitis, which is difficult to manage and has a poor prognosis. Our study aimed to investigate factors affecting clinical outcomes in peritoneal dialysis patients with refractory peritonitis over a 12-year period at a medical faculty hospital in Turkey. We conducted a retrospective study at a single center from January 2009 to December 2020, involving 135 patients with 236 episodes of refractory peritonitis. The average age of the patient cohort was 53.0 ± 15.9years, and 72 (53.4%) of the patients were male. The leading identified causes of end-stage kidney disease were glomerulonephritis, hypertensive glomerulosclerosis, and diabetic nephropathy. Data on microbiological etiology, dialysate white blood cell counts, and patient demographics were analyzed to identify catheter removal risk factors. Statistical significance was set at p ≤ 0.05. Comparative analysis between patients with and without catheter loss revealed no significant differences in gender, age, presence of diabetes, prior hemodialysis, or duration of peritoneal dialysis. However, multivariate logistic regression analysis showed thata dialysate white blood cell count exceeding 1000/mm3 on day 5and hospitalization had a positive associationwith catheter loss, while the presence of gram-positive bacterial growth had an inverse correlation. Our study shows that fifth-day dialysate white blood cell count predicts refractory peritonitis outcomes. Future research should focus on developing tools to manage catheter removal proactively and enhance patient prognosis.

Linking clinical manifestations and causative organisms may provide clues for the treatment of peritoneal dialysis-associated peritonitis

IntroductionDifferent initial manifestations of peritoneal dialysis-associated peritonitis (PDAP) may depend on the type of pathogenic organism. We investigated the association between the clinical characteristics of PDAP and susceptibility to vancomycin and investigated the possibility of using vancomycin monotherapy alone as an initial treatment regimen for some PDAP patients to avoid unnecessary antibiotic exposure and secondary infection.MethodsPatients with culture-positive PDAP were retrospectively analyzed and divided into two groups: peritonitis with only cloudy effluent (PDAP-cloudy) or with cloudy effluent, abdominal pain and/or fever (PDAP-multi). The bacterial culture of PD effluent and antibiotic sensitivity test results were compared between groups. Logistic regression was used to investigate factors predicting susceptibility to vancomycin.ResultsOf 162 episodes of peritonitis which had a positive bacterial culture of PD fluid, 30 peritonitis were in the PDAP-cloudy group, and 132 peritonitis were in the PDAP-multi group. Thirty (100%) peritonitis in the PDAP-cloudy group had gram-positive bacterial infections, which was significantly greater than that in the PDAP-multi group (51.5%) (P < 0.001). Twenty-nine (96.7%) peritonitis in the PDAP-cloudy group were susceptible to vancomycin, compared to 67 (50.8%) in the PDAP-multi group (P < 0.001). The specificity of PDAP-cloudy for vancomycin-sensitive peritonitis was 98.48%. Only one patient (3.3%) in the PDAP-cloudy group experienced vancomycin-resistant peritonitis caused by Enterococcus gallinarum, which could neither be covered by vancomycin nor by the initial antibiotic regimen recommended by the current ISPD guidelines. The presence of only cloudy effluent was an independent predictor of susceptibility to vancomycin according to multivariate analysis (OR = 27.678, 95% CI 3.191-240.103, p = 0.003), in addition to PD effluent WBC counts (OR = 0.988, 95% CI 0.980–0.996, p = 0.004), diabetes mellitus (OR = 3.646, 95% CI 1.580–8.416, p = 0.002), first episode peritonitis (OR = 0.447, 95% CI 0.207–0.962, p = 0.039) and residual renal creatinine clearance (OR = 0.956, 95% CI 0.918–0.995, p = 0.027). Addition of these characteristics increased the AUC to 0.813 (95% CI 0.0.749–0.878, P < 0.001). The specificity of presenting with only cloudy effluent for vancomycin-sensitive peritonitis was 98.48%.ConclusionsCloudy dialysate, as the only symptom at PDAP onset, was an independent predictor of vancomycin-sensitive PDAP, which is an important new insight that may guide the choice of initial antibiotic treatment.

Intraperitoneally Administered Vancomycin Results in Suboptimal Serum and Peritoneal Effluent Drug Levels in Patients with PD-related Peritonitis

Background Intraperitoneal vancomycin is commonly used to treat peritoneal dialysis (PD)-related peritonitis. Therapeutic drug level monitoring helps optimize the use of vancomycin in CKD patients. We studied whether sufficient serum levels were achieved in patients with PD-related peritonitis treated with the commonly used dose of vancomycin in patients with end stage renal disease. Materials and Methods All consecutive patients with PD-related peritonitis during 19 months were studied. Patients received IP Vancomycin 15 mg/kg Q96H and amikacin 2 mg/kg while awaiting culture reports. Vancomycin concentration in serum and dialysate was determined by a validated liquid chromatography-tandem mass spectrometry assay at 1, 12, 24, and 96 h. The primary outcome was the drug levels in serum and peritoneal fluid, and the secondary outcome was peritonitis treatment failure. Results A total of 45 episodes of PD-related peritonitis were treated, of which 41 fulfilled the inclusion criteria and were included in the PK analysis. Recommended serum vancomycin trough level of &gt;15 mg/L was achieved in only two cases. Twenty-one episodes required catheter removal. Conclusion In patients with PD-related peritonitis, intermittent intraperitoneal administration of 15 mg/kg of vancomycin every 96 h does not achieve the recommended serum and dialysate levels of vancomycin. There is an urgent need for pharmacokinetic studies on commonly used IP antibiotics in the PD population to facilitate correct dose recommendations.

Decreased incidence of peritoneal dialysis-associated peritonitis in young children.

Peritonitis is the most common complication of peritoneal dialysis (PD). This study aimed to investigate changes in the incidence, risk factors, microbiology, and clinical outcomes of PD-associated peritonitis in the past decades. This was a retrospective study that included children who initiated chronic PD at our institution between 2000 and 2017. The patients were divided into two groups according to the year of initiation: those who initiated PD between 2000 and 2008 and those who initiated PD between 2009 and 2017. The incidence and characteristics of peritonitis were compared between the groups. A total of 184 patients with a median age of 10.2 years were included in this study. Of the patients, 92 experienced 210 episodes of peritonitis. The incidence rate of peritonitis decreased from 0.35 to 0.21 episodes/patient year during the study period (P = 0.001). During the 2000-2008 period, the 2-year peritonitis-free survival rate was significantly lower for patients under 2 years of age than for the other age groups (P = 0.004), whereas this was not observed during the 2009-2017 period. The multivariable Cox proportional hazard model showed that the <2 years age group had a significantly higher risk of developing peritonitis in the 2000-2008 period. However, this was not evident in the 2009-2017 period. The incidence of PD-associated peritonitis decreased, particularly in children under 2 years of age. Thus, younger age may not be a risk factor for PD-associated peritonitis.

Development and validation of a nomogram for predicting refractory peritoneal dialysis related peritonitis

Objective To identify the risk factors of refractory peritoneal dialysis related peritonitis (PDRP) and construct a nomogram to predict the occurrence of refractory PDRP. Methods Refractory peritonitis was defined as the peritonitis episode with persistently cloudy bags or persistent dialysis effluent leukocyte count >100 × 109/L after 5 days of appropriate antibiotic therapy. The study dataset was randomly divided into a 70% training set and a 30% validation set. Univariate logistic analysis, LASSO regression analysis, and random forest algorithms were utilized to identify the potential risk factors for refractory peritonitis. Independent risk factors identified using multivariate logistic analysis were used to construct a nomogram. The discriminative ability, calibrating ability, and clinical practicality of the nomogram were evaluated using the receiver operating characteristic curve, Hosmer–Lemeshow test, calibration curve, and decision curve analysis. Results A total of 294 peritonitis episodes in 178 patients treated with peritoneal dialysis (PD) were enrolled, of which 93 were refractory peritonitis. C-reactive protein, serum albumin, diabetes mellitus, PD duration, and type of causative organisms were independent risk factors for refractory peritonitis. The nomogram model exhibited excellent discrimination with an area under the curve (AUC) of 0.781 (95% CI: 0.716–0.847) in the training set and 0.741 (95% CI: 0.627–0.855) in the validation set. The Hosmer–Lemeshow test and calibration curve indicated satisfactory calibration ability of the predictive model. Decision curve analysis revealed that the nomogram model had good clinical utility in predicting refractory peritonitis. Conclusion This nomogram can accurately predict refractory peritonitis in patients treated with PD.

Risk factors of peritoneal dialysis-related peritonitis in the Japan Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS).

Peritoneal dialysis (PD)-related peritonitis is a major complication of PD. Wide variations in peritonitis prevention, treatment strategies and consequences are seen between countries. These between-country differences may result from modifiable risk factors and clinical practices. A total of 1225 Japanese PD patients were included and prospectively followed in the Peritoneal Dialysis Outcomes and Practice Patterns Study phase 1 (2014-2018) and phase 2 (2018-2022). Associations between PD-related peritonitis and various risk factors were assessed by Cox proportional hazards survival models. During follow-up (median 1.52years), 539 peritonitis episodes were experienced by 364 patients. The country crude peritonitis rate was 0.27 episodes/patient-year. In the fully adjusted model, noticeable patient-level factors associated with experiencing any peritonitis included age {hazard ratio [HR] 1.07 per 5-year increase [95% confidence interval (CI) 1.01-1.14]}, serum albumin level [HR 0.63 per 1g/dl higher (95% CI 0.48-0.82)] and continuous ambulatory peritoneal dialysis (PD) [HR 1.31 versus automated PD (95% CI 1.05-1.63)]. The adoption of antibiotic prophylaxis practice at the time of PD catheter insertion [HR 0.63 (95% CI 0.51-0.78)] or when having complicated dental procedures [HR 0.74 (95% CI 0.57-0.95)] or lower endoscopy [HR 0.69 (95% CI 0.54-0.89)] were associated with lower hazards of any peritonitis, while a routine facility practice of having more frequent regular medical visits was associated with a higher hazard. Identification of risk factors in Japan may be useful for developing future versions of guidelines and improving clinical practices in Japan. Investigation of country-level risk factors for PD-related peritonitis is useful for developing and implementing local peritonitis prevention and treatment strategies.

Pseudotumor Cerebri with Familial Mediterranean Fever in an Adult Patient

Familial Mediterranean fever is an autosomal recessive disease characterized by recurrent episodes of fever, peritonitis, pleuritis and arthritis. Neurological involvement in FMF is rare but serious. Headache, seizures, demyelinating lesions, stroke, posterior reversible leukoencephalopathy syndrome, aseptic meningitis and cranial neuropathy have been reported in the literature. In this paper, we present a combination of FMF and pseudotumor cerebri in an adult patient.

Improving self-dependency in Pakistan: Experience of a locally prepared automated PD machine.

The increasing burden of haemodialysis on healthcare systems merits efforts to make peritoneal dialysis (PD) more accessible to the population in need of kidney replacement therapy. Automated PD (APD) may be a suitable alternative to continuous ambulatory peritoneal dialysis for home dialysis especially for children, elderly and patients who lead a busy schedule in their jobs thus leaving more time for personal and family activities during the day. Recently, a local bioengineering company took the initiative to develop a locally manufactured, low-cost APD cycler in Pakistan, with an aim to improve the self-dependency and home-based kidney replacement therapy. We herein present our first experience of APD on this locally manufactured APD cycler. It was an investigator-led study on the utility of a locally manufactured APD cycler and the safety and efficacy of the standard operating procedures developed and adopted by the study authors. A total of eight patients agreed to participate in this study extending from September 2021 to August 2022. There were four male and four female patients, and the mean age was 52.5 + 19.71 years. The locally manufactured cycler provided more than 1600 h of APD sessions. The APD sessions were well tolerated with only a few instances of minor mechanical and software issues that did not require termination of therapy. There were no episodes of peritonitis; however, one of the patients had an episode of exit site and tunnel infection that did not seem to be related to the procedure. Our experience with locally manufactured APD cycler was successful and without major adverse events. We believe the locally produced APD cycler is a viable cost-effective option for patients requiring PD and may herald a new era of self-dependency for patients considering or undergoing PD in Pakistan.

Effect of a Management Algorithm for Wet Contamination of Peritoneal Dialysis System on the Prevention of Peritonitis: A Prospective Observational Study

Introduction: Wet contamination was a common problem of peritoneal dialysis (PD) system. We developed a management algorithm for wet contamination of PD system (wet contamination) on the basis of the related research literature and clinical practice experience. The purpose of this study was to observe clinical effect of the management algorithm on the prevention of peritonitis. Methods: Patients treated wet contamination in a single PD center between October 2017 and September 2022 were included. A management algorithm was established to treat wet contamination. It comprised identification of the contamination type, addressing contaminated or aging catheters, prophylactic antibiotics, and retraining. Demographic data and clinical data about wet contamination were collected and compared. Results: One hundred and forty-one cases of wet contamination were included in this study. The mean age was 51.7 ± 14.1 years, and 49.6% were female. The proportion of diabetic nephropathy was 9.9%. The median PD duration was 27.0 (1.7–79.7) months. Eighteen episodes (12.8%) of wet contamination-associated peritonitis developed after wet contamination. The main pathogenic bacteria of peritonitis were Gram-positive bacteria (33.3%) and Gram-negative bacteria (27.8%). The incidence of wet contamination-associated peritonitis in the compliance with the management algorithm group was significantly lower than that in the non-compliance with the management algorithm group (0.9 vs. 48.6%; p < 0.001). Non-compliance with management algorithm (OR = 185.861, p < 0.001) together with advance age (OR = 1.116, p < 0.001) and longer distance from home to hospital (OR = 1.007, p < 0.001) were independent risk factors for wet contamination-associated peritonitis. Conclusion: The management algorithm for wet contamination of PD system could reduce the risk of peritonitis.

#1438 Review of the use of peritoneal catheter sealing in peritonitis

Abstract Background and Aims Relapsing peritonitis is a new episode of peritonitis caused by the same microorganism occurring less than 4 weeks after the end of treatment of the previous one. It is associated with the formation of biofilm formation in the lumen of the peritoneal catheter and may lead to its removal. It is associated with increased technique failure, morbidity and mortality and health care costs. The aim of this study is to demonstrate the efficacy of peritoneal catheter sealing with taurolidine-heparin (T-H) in the prevention of relapsing peritonitis and thus avoid more aggressive measures in these cases, such as catheter removal. Method We performed a single-center retrospective analysis study. We analyzed episodes of peritonitis in our peritoneal dialysis (PD) unit over a 5-year period from January 1st 2019 to December 31st 2023. We collected demographic data and risk factors during this period: age, sex, CKD etiology, diabetes, modality, assisted PD, and S. aureus nasal carrier status. We documented peritonitis during the period, causative germs, treatment performed, and catheter sealing. We documented sealing patterns and evolution (cure, recurrence, catheter removal). We performed T-H sealing with a full abdomen and once the treatment had been completed. The catheter sealing with antibiotics was performed right after the intraperitoneal antibiotics’ doses during the treatment. Results We analyzed a total of 84 patients. Demographic characteristics were: mean age 66.5 years (range 24-88 years), 71.4% male, 28.6% diabetic, 45.2% on APD, 11.9% assisted PD, 5.9% nasal S. aureus carriers. Etiology of CKD: 66.7% unaffiliated etiology, 11.9% glomerulonephritis, 7.1% ADPKD, 5.9% chronic tubulo-interstitial nephritis and 1.2% vasculitis, multiple myeloma, anephritis, acute tubular necrosis, lupus, Alport syndrome and nephronophthisis. There were 71 episodes of peritonitis, in 32 patients. The causative germs were: 36.6% coagulase negative staphylococci, 21.1% streptococci, 19.7% negative culture, 7% enterobacteria, 7% polymicrobial, 4.2% S. aureus, 2.8% enterococci and 1.4% corynebacteria. We performed some type of sealing in 47 peritonitis cases: 34% with antibiotic alone, 21.3% with antibiotic plus T-H and 44.6% with T-H alone. A total of 55.3% of the sealings were performed in peritonitis caused by coagulase-negative staphylococci, 65.4% of which were sealed with T-H or antibiotic plus T-H (Table 1). Two of the peritonitis relapsed with conventional treatment (unsealed or sealed with antibiotic) and, after sealing the peritoneal catheter with T-H, no recurrence was observed. The catheter was removed from a patient with peritonitis plus S. aureus tunnelitis, a new catheter was placed deferred, but he had a new episode of peritonitis with S. aureus tunnelitis and the catheter was removed again; this patient's case is special as he has not maintained adequate hygiene measures in addition to lack of adherence to therapy. Conclusion Peritoneal catheter sealing, especially with T-H, appears to be effective in the treatment and prevention of relapsing peritonitis. In our case, we did not observe any recurrent peritonitis after its use. Despite its widespread use, there are hardly any studies on its use and the most recommendable guidelines for its use, which is why we believe that further studies should be conducted to establish guidelines and methods for its use.

#1980 Past peritonitis episodes are linked to decreased peritoneal Immune Cell Function and Associated with Chronic Increased Peritoneal Inflammation

Abstract Background and Aims Chronic peritoneal inflammation and infectious complications occur in a significant proportion of PD patients. A relationship between peritoneal IL-6 levels and local immunocompetence is suspected. To analyse local immunocompetence, an ex-vivo stimulation assay of PD effluent was developed. The aim of this study was to analyse peritoneal inflammation and immunocompetence in a PD cohort in relation to clinical outcomes. Method Prospectively, 245 routinely performed 4-hour PETs (143 patients, 2679 patient-months) of patients exclusively receiving 2. generation PD fluids (two-chamber, pH neutral, low amount of glucose degradation products) were analysed. An ex-vivo cell stimulation protocol of the fresh effluents was performed of all PETs. Peritoneal immune cell function was analysed using ex-vivo Toll-like receptor (LPS/Pam3Cys) stimulated IL-6 release as an index of immunocompetence. The molecular effects of effluent components and the addition of alanyl-glutamine to PD fluid were analysed in heterologous cell stimulation experiments and using an effluent proteomics and metabolomics approach. Results IL-6 in the effluent showed no association with various patient characteristics (incl. RRF, underlying disease, peritonitis episodes, time on PD). A significant association of peritoneal IL-6 with solute transport rates and systemic markers of uremic inflammation was found. IL-6 in effluent (HR 2.54) and stimulated 1 h effluent (HR 0.34) was predictive of subsequent peritonitis episodes. An inverse association was observed with ex-vivo stimulated IL-6 release from peritoneal cells (P = .02), most pronounced in patients with a history of peritonitis (P = .008). Patients with above median elevated IL-6 levels showed reduced peritoneal immune cell function. The results were validated in an independent multi-centre PD cohort (n = 48). A proteomics (n = 17) and targeted metabolomics (patients n = 134, 1004 metabolites) analysis of PD effluents show an overrepresentation of apoptosis and neutrophil degranulation pathways in patients with elevated effluent IL-6 levels and reduced response mechanisms to pathogens when compared to effluents from patients with low effluent IL-6 levels. Heterologous donor-PBMC stimulation (4 Healthy donors) with 4h PET PD-effluents of 20 patients showed reduced immunocompetence with elevated IL-6 (P = .038) and improved immunocompetence when 8 mM alanyl-glutamine were added to the PD fluid during the dwell. These results could also be validated in a post-hoc analysis of a RCT testing alanyl-glutamine addition to PD fluid for 8 weeks in PD patients. Conclusion This is the first longitudinal study to show the relationship between peritoneal inflammation and impaired immune function of peritoneal cells, possibly predisposing to infectious complications. The possible underlying mechanistic link may represent the biological correlate (“immune-paralysis”) for PD patients at increased risk for recurrent episodes of peritonitis.

#2650 A novel approach for exit site care reduces peritoneal dialysis catheter related infections

Abstract Background and Aims Peritoneal dialysis (PD) related infections, including peritonitis and catheter related infections, are associated with significant morbidity and technique failure. Various exit site care protocols are available, most allow to shower in running water after the exit site is well healed. Following an increase in exit site infections (ESI) in our dialysis unit, partially resulting from water derived organisms, we implemented a novel exit site care protocol. The protocol included complete avoidance of water exposure using stoma bag during shower; and change in antibiotic treatment from gentamycin to mupirocin. We aimed to evaluate its efficacy to decrease ESI episodes. Method A prospective single center trial. Study group included PD patients between June 2018 - May 2021 who implemented the new exit-site care protocol. They were compared to a historical control group that included all PD patients between January 2016 to May 2018. In the control group, exit-site care included a daily shower with a bactericidal cleanser containing chlorhexidine 4%, thereafter local gentamycin 0.1% was applied with sterile gauze dressing. In the study group, water exposure during daily wash was avoided using a stoma bag sealed around the catheter exit-site and the tubing. Thereafter, the exit-site was cleaned with a chlorhexidine 0.5%- alcohol 70% solution and local mupirocin 2% was applied with a sterile gauze cover. Primary outcome was catheter related infections, including ESI and tunnel infection. Secondary outcomes were peritonitis and technique loss. Results A total of 113 patients were included, 58 patients in control and 55 in study group. Mean follow up time was 13.28 ± 9.5 months in control and 16.4 12.7 months in study group. ESI rate was significantly lower in study group (0.11/patient year) compared to control group (0.71/ patient year), p&amp;lt;0.001. Time to first ESI was significantly longer in study group, χ² (1) = 25.104, p &amp;lt; 0.001 (Fig. 1). On multivariate logistic regression analysis confirmed the protective effect of the intervention on ESI risk (p &amp;lt;0.001). Longer PD vintage and active cancer predicted ESI (p = 0.01 and 0.02, respectively). There were no tunnel infections during study period compared to 3 episodes during control. Peritonitis rate was significantly lower in study group (0.19/patient years) compared to control group (0.40/patient years), p=0.011. There was no difference in time to first peritonitis episode between groups χ² (1)=2.32, p=0.128. Nine patients were lost to PD due to PD related infection in control group, compared to 5 in study group. Peritonitis related mortality occurred in one patient in control group. Conclusion Protection of exit site from water exposure in conjunction with local Mupirocin cream reduced significantly ESI and peritonitis episodes in peritoneal dialysis patients. This protocol may be more beneficial in areas of poor water quality.

#2920 Peritoneal dialysis for volume overload in heart failure: a single-center experience

Abstract Background and Aims While diuretics are considered the first-line therapy to control volume overload in heart failure (HF), diuretic resistance can develop, limiting the effectiveness of pharmacological therapy. Peritoneal dialysis (PD) is a kidney replacement therapy usually implemented in advanced or acute kidney failure. However, it can be used to allow ultrafiltration and volume control in refractory cases, either due to kidney or refractory congestive HF. The aim of this study was to describe a single-center experience and study the clinical outcomes of a population of patients with HF that initiated PD for volume control. Method Retrospective single-center study with patients who started PD for volume control between January 1st 2011 and December 31st 2023, with a follow-up of 12 months after start of dialysis or until technique dropout. Demographic and clinical information regarding comorbidities, characteristics of HF, therapeutic management and markers of volume overload (NT-proBNP and CA-125) was collected. The impact on both therapy management and overload markers after six months of PD was also studied. Results Nineteen patients were included in this study, 78.9% of male gender and with a mean age of 63.4 ± 17.2 years. Comorbidities included diabetes in 63.2%, hypertension in 73.7%, coronary arterial disease in 57.8% and peripheral arterial disease in 26.3%. The NYHA (New York Heart Association) class was III or IV in 12 patients (63.1%), with an average left ventricle ejection fraction of 40% ± 14.1, due to ischemic and/or valvular causes in 73.7%. PD vintage was 12 months (IQR 0), with a median glomerular filtration rate (GFR) at the start of peritoneal dialysis of 15 ml/min (IQR 11) while nine patients (47.3%) started with a GFR above 15 mL/min. There was an increase in the number of patients being treated with renin-angiotensin-aldosterone system inhibitors, sodium-glucose co-transporter-2 inhibitors and mineralocorticoids receptor antagonists at six months. Outcomes reported low numbers of major adverse cardiac events, episodes of peritonitis and infection of the peritoneal catheter outer orifice. The number of hospitalizations due to HF was also significantly lower after start of PD (p-value = 0.044). There was a decrease in serum NT-proBNP levels after six months of therapy (p-value = 0.571), with a statistically significant decrease in CA-125 (p-value &amp;lt; 0.001). There was only one reported death during follow-up. Conclusion While PD has classically been viewed only as a kidney replacement therapy, it can also be considered a viable option for refractory volume overload associated with HF. Results suggest an optimization of HF guideline-directed therapy and a decreased number of hospitalizations, with consequent better management of the disease and improved quality of life. There was no negative impact associated with the implementation of PD in this population, with the decrease in CA-125 serum levels also suggesting an overall decrease of volume overload with this technique.

#1262 Risk factors of peritoneal dialysis associated peritonitis caused by gram-negative bacteria: a single-center retrospective study over 16 years

Abstract Background and Aims To analyse the clinical characteristics, pathogen distribution, and treatment outcomes of peritoneal dialysis associated peritonitis (PDAP) caused by gram-negative bacteria, and explore the risk factors for the occurrence and treatment failure of gram-negative bacterial peritonitis. Method We performed a single-center retrospective study included 544 PD patients who underwent regular follow-up between January 1, 2007, and December 31, 2022. After excluding culture-negative peritonitis, fungal peritonitis, and tuberculous peritonitis, based on the pathogens, all episodes were divided into the gram-negative peritonitis group (GNP) and the non-gram-negative peritonitis group (non-GNP). Demographic characteristics, laboratory examinations, pathogenic bacteria, and treatment outcomes were collected and compared between the two groups of peritonitis. Results Over the course of 16 years, 297 episodes of peritonitis occurred in 179 patients. Although the overall incidence of peritonitis is showing a year-on-year downward trend, the incidence of GNP has not changed significantly. However, the percentage of GNP cases among all peritonitis cases is on the rise. After excluding episodes of culture-negative peritonitis, fungal peritonitis, and tuberculous peritonitis, a total of 226 cases of peritonitis were included in the study. Among them, females accounted for 50.0%, with an average age of 63.04 ± 11.58 years and a median PD duration of 42 (21, 73) months. Escherichia coli was the main pathogen responsible for gram-negative bacterial peritonitis in our center (37/80, 46.3%), followed by Klebsiella pneumoniae (9/80, 11.3%). The GNP group had significantly higher white blood cell counts in peritoneal effluent on day 0, day 3, and day 5 after peritonitis onset compared to the non-GNP group (p &amp;lt; 0.001 for all). In terms of treatment outcomes, the GNP group had significantly higher rates of developing refractory peritonitis, treatment failure, and peritonitis-associated death compared to the non-GNP group (p &amp;lt; 0.001 for all). Multivariate logistic regression analysis revealed that enteric infection was an independent risk factor for GNP occurrence (OR = 6.315, 95% CI 3.364-11.854, p &amp;lt; 0.001). White blood cell counts on day 3 of peritoneal effluent (OR = 2.666, 95% CI 1.099-6.469, p = 0.030) and post-PDAP blood white blood cell counts (OR = 1.389, 95% CI 1.060-1.820, p = 0.017) were independent risk factors for treatment failure in GNP. Conclusion Over the past 16 years, the incidence rate of GNP in our center has shown no significant decrease, and the proportion of GNP cases has been increasing year by year. Escherichia coli is the main pathogen responsible for GNP in our center. GNP cases are more difficult to treat and have a poorer prognosis compared to non-GNP cases. Therefore, it is important to strengthen preventive measures for peritoneal dialysis patients, reduce the risk of enteric infection, and actively treat patients who have already developed gram-negative bacterial peritonitis to avoid adverse outcomes.

#2355 Eradication of Staphylococcus aureus carriage in patients undergoing peritoneal dialysis

Abstract Background and Aims Peritonitis is a common and serious complication of peritoneal dialysis (PD). A single episode of severe peritonitis or multiple peritonitis episodes frequently leads to diminished peritoneal ultrafiltration capacity, hospitalization, and a switch to hemodialysis. Prevention of infection is the mainstay for the reduction of peritonitis rate. According to the current guidelines, we use nasal antibiotic prophylaxis if patients are identified as nasal Staphylococcus aureus carriers on screening prior to PD beginning. Eradication of S. aureus Regular with nasal mupirocin reduces the rate of exit-site infections but has uncertain effects on the risk of peritonitis. The aim of this study was to evaluate the rate of S. aureus peritonitis in our cohort of patients receiving PD. Method A retrospective single-center study was conducted in a large Italian PD center. We reviewed all cases of bacterial peritonitis from 1999 to 2023. Demographic and clinical characteristics of the patients and microbiological features of the bacteria identified in cultures were extracted from electronic health record. From 2011, all patients were screened before surgery for Methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) with nares swabs. All patients with positive nasal colonization for MSSA and MRSA were treated with nasal mupirocin (nasal ointment twice daily for 5 consecutive days every 4 weeks) until eradication was confirmed by a nasal swab. According to our protocol, from 2011, screening for S. aureus carriage along peritoneal fluid culture was performed in all patients on PD with an episode of peritonitis to verify nasal colonization with S. aureus. The study was approved by the regional ethical committee of Emilia Romagna (507/2021/OSS/AOUMO SIRER ID 2845). Results Overall, 345 cases of peritonitis were reviewed in 214 patients who received peritoneal dialysis. In our center, the rate of peritonitis was 0.23 episodes/patient-year. After the introduction of nasal screening for S. aureus carriage, the episodes of S. aureus peritonitis decreased in frequency (0.0093 episodes/patient-year vs. 0.034 episodes/patient-year) and as absolute number (17.8% vs 3.6%; p = 0.001). No differences were observed in the rate of catheter removal in the two populations (p = 0.99). The age of 109 patients screened for S. aureus carriage was 64.1 ± 17 years. Males accounted for 58.9% and automated PD (APD) was chosen by 66% of the subjects. After an average period of 1.6 years from the start of PD, 7 patients experienced S. aureus peritonitis in the absence of exit-site or tunnel catheter infection. Nasal screening at the time of peritonitis showed that half of them were carriers of S. aureus and half were negative (one patient was not screened). Colonization from S. aureus was found in another 9 patients whose peritonitis was caused by a different type of bacteria (44% S. epidermidis, 33.3% Enterobacteriaceae, 11.1% Acinetobacter, and 11.1% culture-negative peritonitis). Conclusion Our data document that screening for S. aureus, along with other preventive measures, contributes to significantly reducing the rate of S. aureus peritonitis in patients screened and treated for S. aureus carriage at the time of PD start. Routine screening and the use of a mask during connection are required because recolonization occurs frequently in this population.

#1513 Update on the peritonitis trend in central Spain

Abstract Background and Aims Peritonitis is one of the most common and severe complications associated with peritoneal dialysis (PD) traditionally cited as the primary cause of catheter loss and discontinuation of the dialysis technique. Nevertheless, the incidence and severity of peritonitis has been significantly reduced over time. Therefore, we aimed to update the current impact of peritonitis in PD patients. Method We performed an observational, multi-centre, prospective cohort including 3,037 patients who started PD between 2003-2020 followed for a median of 1.6 [0.8-2.9] years. Results We observed 2 941 episodes of peritonitis, with a peritonitis rate (PR) of 0.46 episodes per patient year and a mean of 2.6 years CI 95% [2.4-2.8] to first peritonitis episode. As expected, gram-positive organism was identified in the 69.3% of the cases, followed by gram-negative (19.6%) and sterile culture (15.6%). The usual course of the peritonitis is favourable, with complete recovery in the 76.4% of the cases, whereas just the 37.6% require admission during a median of 5 [3-9] days, with a peritonitis recurrence of 11.2%. A fatal peritonitis (resulted in PD cessation) was observed in 11.7% of the patients with an overall mortality of 0.7% (considering all the deaths within the 90 days after peritonitis). Factors associated with a 90-days mortality rate related to PD rate were age &amp;gt; 65 years (OR 2.99 [1.84-4.85]), Charlson index (OR 1.19 [1.07-1.33]), and the type of microorganism: fungus (OR 9.8 [4.16-23.43], multi-bacterial (OR 7.97 [0.91-69.88] and gram- negative OR (2.41 [1.45, 3.99]). Comparing patients who developed peritonitis (P) (N = 1230) vs patients who not developed peritonitis (NP) (N = 1807), P patients were older (P 59 ± 15.5 years vs NP 55 ± 15.5 years, p &amp;lt; 0.001) and associated higher comorbidity (such as Charlson index, cardiovascular and diabetes mellitus history) than NP patients. P patients more commonly had a prior history of renal replacement therapy (kidney transplant P 9.2% vs NP 6.9% and hemodialysis 18.8% vs 17.1%) compared with NP patients. PR has significantly decreased over three consecutive 5-year periods: from 0.51 [0.48-0.54] peritonitis cases per year during 2003-2008 to 0.45 [0.43-0.48] during 2009-2014 (p 0.03), and further dropping to 0.41 [0.38-0.44] for the period 2015-2020 (p &amp;lt; 0.001). Conclusion Over the past 17 years, the incidence and severity of peritonitis have significantly reduced, despite PD patients becoming older and associated high comorbidities.

#988 Peritoneal dialysis related peritonitis: insights from a long-term analysis of an Italian center

Abstract Background and Aims Peritonitis is a common and severe complication of peritoneal dialysis (PD). For comparative analysis standardized definitions are crucial, but most studies have been used heterogenous methods to measure outcomes. The ISPD 2022 guidelines have revised and clarified numerous definitions and proposed new peritonitis categories. Thus, deeper comprehension concerning the incidence, prevalence, and outcome of cause- and time specific peritonitis in contemporary cohorts is required. Method Between 1st January 2009 and 31st May 2023, 267 patients who started PD at our institution were included in the study (Tab. 1). All PD-related peritonitis episodes that occurred in our unit during the study period were collected. The new definitions and outcomes of ISPD 2022 recommendations were employed. Results During the study period 113 patients (42.3%) experienced 219 peritonitis (Tab. 2). The overall peritonitis rate was 0.25 episode/patient year. During the study period, 230 patients (88.5%) discontinued the dialytic technique; among them 122 were transferred to HD. Peritonitis represented the main cause of hemodialysis (HD) transfer (35.2%). Patient cumulative probability of remaining peritonitis-free at one year was 84.2%. The initial antibiotic regimen (cefazolin in association with tobramycin ip) was effective in 131 episodes (141/219, 64.3%), while the medical cure and refractory peritonitis rates were equal to 70.3 and 22.4%, respectively. The rates of peritonitis associated death, HD transfer, catheter removal and hospitalization were 6.8%, 18.3%, 18.7% and 64.4%, respectively. Relapsing, repeat, recurrent and enteric peritonitis accounted for 7.8%, 6.8%, 4.1% and 2.7% of all episodes, respectively. Catheter insertion, catheter related and pre-PD peritonitis were 4.2, 2.1 and 0.5%. Gram-positive and Gram-negative bacteria accounted for 74.1% and 21.3% of peritonitis, respectively. Initial antibiotic regimen was more effective in Gram-positive (76.4%) than Gram-negative (35.1%) microorganisms (p &amp;lt; 0.0001). Culture-negative peritonitis accounted for 25.6% of all specimens. In comparison with positive-culture peritonitis, culture-negative episodes showed a higher medical cure rate (88.4%, 46/52 vs 68.9%, 104/151; p &amp;lt; 0.01) and were significantly less likely to be complicated by hospitalization (48.1%, 25/52 vs 72.2%, 109/151; p &amp;lt; 0.05), catheter removal (9.6%, 5/52 vs 22.5%, 34/151; p &amp;lt; 0.05), HD transfer (9.6%, 5/52 vs 21.9%, 33/152; p &amp;lt; 0.05) and death (0%, 0/52 vs 8.6%, 13/151, p &amp;lt; 0.05). However, initial antibiotic regimen response was similar between culture-negative and culture-positive episodes (71.2%, 37/52 vs 62.3%, 94/151, p = ns). Rates of relapsing, repeat and recurrent peritonitis were 0.023, 0.018 and 0.011 episode/patient-year, respectively accounting for 7.8, 6.8 and 4.1% of all episodes The composite outcome of either catheter removal or death due to peritonitis was higher in relapsing (42.1%, 8/19, p &amp;lt; 0.05) and recurrent (44.4%, 4/9, p &amp;lt; 0.05) episodes than generic peritonitis (19.1%, 34/178) but similar to repeat peritonitis (3/15, 20%, p = ns). Although peritonitis from enteric causes represented only 2.7% of all episodes, they needed catheter removal in one-third of events (33.3%) and caused patient death (66.6%) in the remaining cases. Conclusion Although representing the leading cause of HD transfer cause, more than 50% of incident PD patients never experienced peritonitis. Carrying a worse outcome than generic peritonitis, entities such as relapsing, recurrent and enteric peritonitis should be aggressively treated. Conversely, culture-negative peritonitis showed a better prognosis as compared to positive-culture episodes. However, aiming at the prevention of microbial resistances, the reduction of culture-negative cases is necessary to minimize patient exposure to empiric therapy with multiple antibiotics. In our experience first-line empirical antibiotic therapy was effective in almost 65% of the cases. Nevertheless, the efficacy of this regimen was unsatisfactory in Gram-negative microorganisms requiring further microbiological and pharmacokinetic evaluation.

#1125 CAPD in ESRD and CLD patients with refractory ascites: a 12-month follow-up study

Abstract Background and Aims Refractory ascites secondary to chronic liver disease among ESRD patients are a major source of morbidity and mortality. Hemodialysis is frequently interrupted due to intradialytic hypotension and other complications which make ultrafiltration removal among CLD patients, a big challenge. This results in sub-optimal clearance which translates into poor quality of life along with recurrent admissions. CAPD in these patients is effective in providing a good clearance as well as removal of ascites with adequate ultrafiltration removal. There is a lack of data regarding the feasibility, safety, and clinical outcomes of CAPD among CLD patients with ascites. We conducted a study with objectives to evaluate serum albumin levels at baseline and 12 months, and to determine peritonitis rates and dialysis modality suitability in CLD patients. Method Study Design A retrospective cohort study. Study Population All hemodialysis patients with refractory ascites due to CLD. Refractory ascites was defined as the need for &amp;gt;5 therapeutic paracentesis in the last 3 months after optimal clinical, dietary and fluid management. All CLD patients were extensively counselled regarding high protein intake. Each patient visited either the Nephrologist or PD Nurse, renal dietician at least once in 4-6 weeks. Results Over a period of five years, 34 patients were included in the analysis to assess the efficacy of Continuous Ambulatory Peritoneal Dialysis (CAPD) for ascites management in chronic liver disease. Baseline characteristics are presented in Table 1. The frequency of ascites drainage prior to CAPD was every 3.4 weeks. Open catheter insertion was performed in 31 out of 34 patients. Serum albumin levels increased from 2.98 ± 0.4 g/dL at baseline to 3.1 ± 0.28 g/dL at 12 months (p = 0.21) (Fig. 1). Child-Pugh Score and MELD score remained stable. Bacterial peritonitis episodes were higher at 12 months (3 vs 9; p = 0.04). PD-related complications at one year included one omental wrap, three pericatheter leaks, and one umbilical hernia. At the 12-month follow-up, 32 patients survived. One patient died from myocardial infarction, and another experienced severe hepatic encephalopathy and aspiration pneumonia. Conclusion PD was well tolerated in patients with refractory ascites, presenting no additional hypoalbuminemia risk. Continuous multidisciplinary monitoring for malnutrition remains critical. Peritonitis risk was elevated relative to SBP in HD patients yet was on par with typical PD rates, without an increase in hospital admissions.

Cognitive Dysfunction Screening in Peritoneal Dialysis Patients: A Cross-Sectional Study.

Mild cognitive impairment (MCI) in peritoneal dialysis (PD) patients has been described as a risk factor for worse outcomes such as peritonitis, technique failure, and mortality. In this study, we aimed to determine the prevalence of MCI in a population of PD patients and identify the possible risk factors associated with MCI. We performed an observational, cross-sectional study to evaluate cognitive function using the Montreal Cognitive Assessment (MOCA) test and the Mini Mental State Examination (MMSE) test in PD patients. Patients with diagnosis of dementia or severe neurologic impairment, active cancer, or infection were excluded. We evaluated 66 patients (mean age 60 years); 53% were male. Prevalence of MCI assessed by MOCA test and MMSE test was 65% and 33%, respectively. Predictors of MCI with MOCA test were higher age (P = 0.0001), lower education level (P = 0.005), need of a helper (P = 0.009), and continuous ambulatory PD modality (P = 0.019). Higher Charlson comorbidity index (P = 0.002), coronary artery disease (P = 0.006), and peripheral artery disease (P = 0.033) were also associated with MCI. Lower Kt/V (P = 0.012) and lower levels of normalized protein catabolic rate (nPCR; P < 0.000) were related to MCI. MCI patients had more episodes of peritonitis (P = 0.047). Multivariable analysis showed that lower education, Kt/V, and nPCR were the most relevant factors connected to MCI (P = 0.029, P = 0.037, and P = 0.019, respectively). In our PD population, MCI was detected in more than half of the patients. Patients with MCI were older, had lower education level, more disease burden, and higher risk for developing peritonitis. Lower Kt/V and nPCR levels were associated with MCI.