Peritoneal Effluent Research Articles

Peritoneal dialysis fluid biocompatibility impact on human peritoneal membrane permeability.

ABSTRACTBackgroundWe have compared the effects of conventional lactate-based peritoneal dialysis fluid (CPDF) with respect to bicarbonate/lactate-based fluid on peritoneal ultrafiltration (UF) and peritoneal permeability, and on variations on gene expression in cells isolated from effluents of patients’ peritoneal bags.MethodsThis was a non-randomized sequential prospective study including all incident peritoneal dialysis (PD) patients (n = 40) recruited in our centre. Peritoneal equilibration tests (PETs) were performed using CPDF or BPDF both containing 2.27% glucose during a 48-h interval in four different sequences. Gene expression variation of selected genes was measured by reverse transcription polymerase chain reaction in mesothelial cells obtained from the total drained fluid during the PET.ResultsIn the overall study, the use of BPDF was associated with significantly lower mass transfer area coefficient for urea and creatinine, longer accelerated peritoneal examination test times for urea and creatinine, lower total pore area available for exchange over diffusion distance and lower UF. There were no differences in the gene expression of aquaporins 1–3, endothelial and inducible nitric oxide synthase (NOS3 and NOS2), or interleukin-6. The SNAIL and E-CADHERIN gene expression normalized ratio was evaluated in peritoneal effluents of cells obtained from CPDF and BPDF. We observed that the SNAIL/E-CADHERIN mRNA ratio decreased when the dialysis sequence started with BPDF and went on to CPDF, but not when the sequence was the opposite.ConclusionThis study shows that those patients who started PD treatment with BPDF were characterized by a better biocompatibility profile. BPDF associates with lower peritoneal permeability to small molecules and lower UF.

Effects of Oral Paricalcitol and Calcitriol Treatment on Peritoneal Membrane Characteristics of Peritoneal Dialysis Patients - A Pilot Study.

Long-term peritoneal dialysis (PD) is frequently complicated by technique failure preceded by peritoneal remodeling. Vitamin D has potent immunomodulatory characteristics: anti-inflammatory, anti-angiogenic, anti-fibrotic properties, and influences on the macrophage phenotype. Little is known about the relation between pleiotropic effects attributed to vitamin D3 and the peritoneal membrane and what is the most appropriate vitamin D sterol in prevention of peritoneal remodeling in PD patients. Animal studies have suggested that paricalcitol has advantageous effects: decrease in plasma markers of inflammation, less peritoneal fibrosis, less pronounced PD-induced omental angiogenesis, and prevention of loss of ultrafiltration. We investigated whether paricalcitol is advantageous over calcitriol in PD patients. A multicenter open-label 1:1 randomized non-blinded clinical pilot study enrolled prevalent continous ambulatory PD (CAPD) patients for a period of 6 months comparing paricalcitol with calcitriol. All patients were treated with biocompatible PD fluids. The primary endpoint was peritoneal transport parameters, exploratory endpoints were biomarkers of peritoneal damage and cell analysis (including M1/M2 macrophages), and safety endpoints were metabolic parameters. Twenty-seven patients were included. Fourteen were randomized to treatment with paricalcitol. There was no difference in peritoneal transport parameters between the groups. We found similar Kt/V, D/P creatinine, D/D0 glucose, ultrafiltration, residual renal function and 24-h urine volume during the study. There was no difference in biomarker concentrations in peritoneal effluents, and no difference in leucocyte differentiation or mesothelial cells between the groups at any time point. Parathyroid hormone (PTH) levels decreased after administration of calcitriol after 12 and 24 weeks compared with baseline (p = 0.001; p = 0.025). Parathyroid hormone levels in the paricalcitol group did not change significantly. In this pilot study we investigated the effect of active vitamin D in PD patients. We found no specific benefit of active vitamin D3 in vitamin D3-sufficient PD patients. Additional studies in preferably incident patients, with an adequate PTH suppression in the intervention groups and during a longer period, are required to test the beneficial effects of active vitamin D3 over no treatment and to investigate whether in 25(OH)D3-deficient PD patients the type of active vitamin D3 matters.

MUL+DO: A multicomponent index for the quick diagnosis of peritonitis in peritoneal dialysis patients

Peritoneal infection is a common problem that has a negative impact on the survival of patients and the technique. The early administration of peritoneal infection treatment reduces complications.The goal of this study is to propose a multicomponent index (MUL+DO) for the quick and efficient diagnosis of peritoneal infection.We selected a training cohort of peritoneal effluent samples which were analyzed by Multistix® 10 SG Siemens test strips for leukocyte detection. Then, each sample was examined according to the gold standard: number of leukocytes, polymorphonuclear percentage and microbiological culture. We constructed the MUL+DO index by adding one point to the MULTISTIX [0-1-2-3] modified chromatic scale if the patient reported pain. The MUL+DO index ranged from 0 to 4. A model validation cohort was then created. MUL+DO was applied to each sample and leukocytes and polymorphonuclear percentage were also assessed.The training cohort ultimately included 134 samples, 34 of which with infection (25.4% [17.6–33.1]). Samples with a MUL+DO value greater than 1 presented a sensitivity and specificity of 100%. The validation cohort included 100 samples with 16 infections (16% [8.3–23.7]).Assuming a sample with a MUL+DO value greater than 1 to be positive, we obtained a sensitivity of 100% and a specificity of 95.2%.The MUL+DO index applied to the training cohort showed a perfect separation of the positive and negative populations. All positive patients presented a score ≥2. In the validation cohort, the MUL+DO reported a sensitivity of 100% and a specificity of 95.2%.

Konjenital nefrotik sendromlu bir infantta periton diyalizine bağlı olarak görülen nadir bir komplikasyon olarak şiloz asit

Chylous ascites is a rare but important non-infectious complication in patients undergoing peritoneal dialysis. A male infant of 1.5-month-old with congenital nephrotic syndrome admitted to our pediatric intensive care unit becasue of deterioration in general appearence, diffuse edematous appearance and respiratory distress. Peritoneal catheter insertion and peritoneal dialysis was performed in the 3rd day of hospitalization. Five days after peritoneal dialysis catheter insertion (on the 8th day of hospitalization) the peritoneal dialysis effluent had a milky appearance. The chemical analysis of the milky effluent showed characteristics of chylous ascites: triglycerides 468 mg/dl. The chylous ascites resolved at the 5th day of our treatment with a low fat diet with medium chain triglycerides and intravenous infusion of somatostatin analogue (octreotide) and the patient was transferred to the pediatric service for maintenance of the treatment.

WNT signaling is required for peritoneal membrane angiogenesis.

The wingless-type mouse mammary tumor virus integration site family (WNT) signaling pathway is involved in wound healing and fibrosis. We evaluated the WNT signaling pathway in peritoneal membrane injury. We assessed WNT1 protein expression in the peritoneal effluents of 54 stable peritoneal dialysis (PD) patients and WNT-related gene expression in ex vivo mesothelial cell cultures from 21 PD patients. In a transforming growth factor-β (TGF-β)-mediated animal model of peritoneal fibrosis, we evaluated regulation of the WNT pathway and the effect of WNT inhibition on peritoneal fibrosis and angiogenesis. WNT1 and WNT2 gene expression were positively correlated with peritoneal membrane solute transport in PD patients. In the mouse peritoneum, TGF-β-induced peritoneal fibrosis was associated with increased expression of WNT2 and WNT4. Peritoneal β-catenin protein was significantly upregulated after infection with adenovirus expressing TGF-β (AdTGF-β) along with elements of the WNT signaling pathway. Treatment with a β-catenin inhibitor (ICG-001) in mice with AdTGF-β-induced peritoneal fibrosis resulted in attenuation of peritoneal angiogenesis and reduced vascular endothelial growth factor. Similar results were also observed with the WNT antagonist Dickkopf-related protein (DKK)-1. In addition to this, DKK-1 blocked epithelial-mesenchymal transition and increased levels of the cell adhesion protein E-cadherin. We provide evidence that WNT signaling is active in the setting of experimental peritoneal fibrosis and WNT1 correlates with patient peritoneal membrane solute transport in PD patients. Intervention in this pathway is a possible therapy for peritoneal membrane injury.

Isolation of bacterial DNA followed by sequencing and differing cytokine response in peritoneal dialysis effluent help in identifying bacteria in culture negative peritonitis.

The treatment of peritoneal dialysis related culture negative peritonitis is empirical which increases the cost of therapy and moreover antibiotic resistance. We aimed the study to isolate bacterial DNA from PD effluent and indentify bacteria causing peritonitis in culture negative situations. We have also studied the cytokine response with different bacteria causing peritonitis. We have isolated bacterial DNA from PD effluent of culture negative and culture positive peritonitis patients. Bacterial DNA was subjected to polymerase chain reaction using universal bacteria specific primers and subsequently to Gram type specific primers for the differentiation of the etiologic agents into Gram-positive and Gram-negative. The amplified products were sequenced and subjected to blast search to identify agent at genus/ species level. Of the 30 molecular method positive samples, 16 (53.33%) samples were positive for Gram-negative bacteria and 4 (13.33%) for Gram-positive, while the remaining10 (33.33%) were positive for both Gram-positive and Gram-negative bacteria. We have found organisms that usually do not grow on normal culture methods. TNF-α was significantly associated with Gram-positive peritonitis and regulatory cytokine IL-10 with Gram-negative peritonitis. The molecular techniques are helpful in detecting and identifying organisms from culture negative PD effluent.

Effluent and serum protein N-glycosylation is associated with inflammation and peritoneal membrane transport characteristics in peritoneal dialysis patients

Mass spectrometric glycomics was used as an innovative approach to identify biomarkers in serum and dialysate samples from peritoneal dialysis (PD) patients. PD is a life-saving treatment worldwide applied in more than 100,000 patients suffering from chronic kidney disease. PD treatment uses the peritoneum as a natural membrane to exchange waste products from blood to a glucose-based solution. Daily exposure of the peritoneal membrane to these solutions may cause complications such as peritonitis, fibrosis and inflammation which, in the long term, lead to the failure of the treatment. It has been shown in the last years that protein N-glycosylation is related to inflammatory and fibrotic processes. Here, by using a recently developed MALDI-TOF-MS method with linkage-specific sialic acid derivatisation, we showed that alpha2,6-sialylation, especially in triantennary N-glycans from peritoneal effluents, is associated with critical clinical outcomes in a prospective cohort of 94 PD patients. Moreover, we found an association between the levels of presumably immunoglobulin-G-related glycans as well as galactosylation of diantennary glycans with PD-related complications such as peritonitis and loss of peritoneal mesothelial cell mass. The observed glycomic changes point to changes in protein abundance and protein-specific glycosylation, representing candidate functional biomarkers of PD and associated complications.

Estimation of lean body mass by creatinine kinetics increases the prevalence of muscle wasting in peritoneal dialysis patients compared to bioimpedance.

Dialysis patients are at increased risk for muscle wasting, and time efficient screening tests are required for to allow for early detection. Creatinine kinetics have been advocated to estimate lean body mass (LBM) in peritoneal dialysis (PD) patients, and can be readily calculated in clinical practice from peritoneal dialysate effluent and urine collections. Bioimpedance is increasingly available, and we compared methods in 434 PD patients (55% men, 33.3% diabetics), mean age 55.2 ± 16.2 years. LBM was lower by creatinine kinetics (47.8 ± 16.6 kg men, 37.8 ± 11.2 kg women) vs. bioimpedance (53.2 ± 11.5 kg men, 39.2 ± 7.2 kg women), p < 0.01. The prevalence of muscle wasting was much greater using creatinine kinetics (72.4% men, 52.4% women) vs. bioimpedance (55.2% men, 37.3%), p < 0.05. Estimates of LBM were much lower using creatinine kinetics compared to bioimpedance. Studies reporting the prevalence of muscle loss in PD patients will differ depending upon the method used to estimate muscle mass.

Prominent Levels of the Profibrotic Chemokine CCL18 during Peritonitis: In Vitro Downregulation by Vitamin D Receptor Agonists.

Peritoneal dialysis (PD) is used as a renal replacement therapy, which can be limited by peritoneal membrane ultrafiltration failure (UFF) secondary to fibrotic processes. Peritonitis, a frequent complication of PD, is a major risk factor for peritoneal membrane fibrosis and UFF. Low peritoneal levels of the chemokine CCL18 are associated with preservation of peritoneal membrane function in PD. Given that CCL18 is involved in fibrotic processes and recurrent peritonitis, it is a risk factor for peritoneal membrane failure; thus, we evaluated CCL18 concentrations in peritoneal effluents from patients undergoing peritonitis episodes. Pharmacological interventions aimed at diminishing the production of CCL18 were also explored. Fivefold higher CCL18 peritoneal concentrations were found during acute bacterial peritonitis, in parallel with the increased infiltration of macrophages. Unexpectedly, CCL18 was also highly (50-fold) increased during sterile eosinophilic peritonitis, and peritoneal eosinophils were found to express CCL18. In vitro treatment of peritoneal macrophages with the vitamin D receptor agonist paricalcitol was able to reduce the secretion and the expression of CCL18 in isolated peritoneal macrophages. In conclusion, our study suggests that the chemokine CCL18 can be a mediator of peritoneal membrane failure associated with peritonitis episodes as well as providing a new potential therapeutic target.

Biologically active form of vitamin B1 in human peritoneal effluent.

Supplementation with vitamin B1 protects the peritoneal membrane from inflammatory and oxidative insults and preserves residual kidney function in rat models of peritoneal dialysis (PD). It is assumed that an active form of vitamin B1, thiamin diphosphate (ThDP), is responsible for this protective effect. However, it has never been shown whether ThDP, a compound known not to cross cellular membranes, is actually detectable in human peritoneal effluent. This study was designed to investigate the concentration, appearance rate, and daily loss of ThDP in the peritoneal effluent of patients treated with PD. We performed 24-hour effluent collection as well as the peritoneal equilibration test (PET) and analyzed the relation between the transport characteristics of the peritoneal membrane and appearance rate of ThDP in a cohort of 26 PD patients. ThDP was detectable in peritoneal effluent in humans. ThDP appearance rate was independent of the transport characteristic of peritoneal membrane, and was not associated with peritoneal transport of other small solutes. We conclude that ThDP can be found in detectable concentrations in the peritoneal effluent in humans and is transported through the peritoneal membrane in a pattern independent of other small solutes. Our finding opens novel opportunities in further research on the protection of peritoneal membrane in humans.

MUL+DO: índice multicomponente para el diagnóstico rápido de peritonitis en pacientes de diálisis peritoneal

Peritoneal infection is a common problem that has a negative impact on the survival of patients and the technique. The early administration of peritoneal infection treatment reduces complications.The goal of this study is to propose a multicomponent index (MUL+DO) for the quick and efficient diagnosis of peritoneal infection.We selected a training cohort of peritoneal effluent samples which were analysed by Multistix ® 10 SG Siemens test strips for leukocyte detection. Then, each sample was examined according to the gold standard: number of leukocytes, polymorphonuclear percentage and microbiological culture. We constructed the MUL+DO index by adding one point to the MULTISTIX [0-1-2-3] modified chromatic scale if the patient reported pain. The MUL+DO index ranged from 0 to 4. A model validation cohort was then created. MUL+DO was applied to each sample and leukocytes and polymorphonuclear percentage were also assessed.The training cohort ultimately included 134 samples, 34 of which with infection (25.4% [17.6-33.1]). Samples with a MUL+DO value greater than 1 presented a sensitivity and specificity of 100%. The validation cohort included 100 samples with 16 infections (16% [8.3-23.7]).Assuming a sample with a MUL+DO value greater than 1 to be positive, we obtained a sensitivity of 100% and a specificity of 95.2%.The MUL+DO index applied to the training cohort showed a perfect separation of the positive and negative populations. All positive patients presented a score ≥2. In the validation cohort, the MUL+DO reported a sensitivity of 100% and a specificity of 95.2%.

A prospective, proteomics study identified potential biomarkers of encapsulating peritoneal sclerosis in peritoneal effluent

Encapsulating peritoneal sclerosis (EPS) is a potentially devastating complication of peritoneal dialysis (PD). Diagnosis is often delayed due to the lack of effective and accurate diagnostic tools. We therefore examined peritoneal effluent for potential biomarkers that could predict or confirm the diagnosis of EPS and would be valuable in stratifying at-risk patients and driving appropriate interventions. Using prospectively collected samples from the Global Fluid Study and a cohort of Greek PD patients, we utilized 2D SDSPAGE/ MS and iTRAQ to identify changes in the peritoneal effluent proteome from patients diagnosed with EPS and controls matched for treatment exposure. We employed a combinatorial peptide ligand library to compress the dynamic range of protein concentrations to aid identification of low-abundance proteins. In patients with stable membrane function, fibrinogen γ-chain and heparan sulphate proteoglycan core protein progressively increased over time on PD. In patients who developed EPS, collagen-α1(I), γ-actin and Complement factors B and I were elevated up to five years prior to diagnosis. Orosomucoid-1 and a2-HS-glycoprotein chain-B were elevated about one year before diagnosis, while apolipoprotein A-IV and α1-antitrypsin were decreased compared to controls. Dynamic range compression resulted in an increased number of proteins detected with improved resolution of protein spots, compared to the full fluid proteome. Intelectin-1, dermatopontin, gelsolin, and retinol binding protein-4 were elevated in proteome-mined samples from patients with EPS compared to patients that had just commenced peritoneal dialysis. Thus, prospective analysis of peritoneal effluent uncovered proteins indicative of inflammatory and pro-fibrotic injury worthy of further evaluation as diagnostic/prognostic markers.

Multiple extracellular vesicle types in peritoneal dialysis effluent are prominent and contain known biomarkers.

Peritoneal dialysis inevitability results in activation of inflammatory processes and its efficiency is highly variable between patients. An improved method to isolate biomarkers and study pathophysiological mechanisms in peritoneal dialysis effluent (PDE) is expected to be of much benefit for the development of this treatment approach and help with patient management. Extracellular vesicles (EVs) are released as part of normal cellular processes. Their proteome is expected to reflect both type and health of their cell of origin. Although there is a significant interest in using EVs for “liquid biopsies”, little is reported of their presence or composition in plentiful dialysis waste fluids, including peritoneal dialysis effluent (PDE). Here we determined the presence of EVs in PDE and subsequently characterized their proteome. EVs were first isolated from PDE using differential centrifugation, then a further enrichment using size exclusion chromatography (SEC) was performed. The presence of EVs was demonstrated using transmission electron microscopy, and their particle counts were investigated using nanoparticle tracking analysis and dynamic light scattering. Using tandem mass spectrometry, marker proteins from three types of EVs i.e. apoptotic bodies, ectosomes, and exosomes were identified. The proteomic results demonstrated that the isolation of EVs by differential centrifugation helped enrich for over 2,000 proteins normally masked by abundant proteins in PDE such as albumin and SEC markedly further improved the isolation of low abundant proteins. Gene ontology analysis of all identified proteins showed the marked enrichment of exosome and membrane-associated proteins. Over 3,700 proteins were identified in total, including many proteins with known roles in peritoneal pathophysiology. This study demonstrated the prominence of EVs in PDE and their potential value as a source of biomarkers for peritoneal dialysis patients.

La péritonite sclérosante et encapsulante

Encapsulating peritoneal sclerosis is a rare but devastating complication of long-term peritoneal dialysis with a high mortality rate. The incidence is between 0.5 and 2.5%, decreasing with time. PSE is defined as a clinical syndrome with signs of gastrointestinal obstruction, inflammation parameters, radiological and macroscopic changes. The duration of treatment and the cessation of peritoneal dialysis are the main risks. About 75% occured in patients on hemodialysis or after kidney transplantation. Morphological alterations are disappearance of mesothelial layer, submesothelial fibrosis, interstitial sclerosis and vasculopathy. Ultrafiltration failure, fast transport status of the peritoneal membrane and loss of sodium sieving, the most powerful predictor, are the functional abnormalities. Biomarkers in peritoneal effluent include cancer antigen 125, interleukin-6. The pathophysiology is probably a consequence of a multiple-hit process in which expression of growth factors and cytokines play a central role. Medical strategies (corticosteroids, tamoxifen) in association with parenteral nutrition and/or surgery (enterolysis) are discussed. Prevention is the use of physiological peritoneal dialysis solutions, icodextrine instead of high glucose concentration solutions and peritoneal lavage after peritoneal dialysis stopping.

THE ASSOCIATION OF DYSLIPIDEMIA WITH INTRAPERITONEAL INFLAMMATION AND PERITONEAL DIALYSIS TECHNIQUE SURVIVAL

The aim of the study was to determine the relationship between the dyslipidemia, intraperitoneal inflammation and peritoneal dialysis (PD) survival.&#x0D; Patients and methods. A total of 40patients with end-stage renal disease treated with continuous ambulatory peritoneal dialysis (PD) have been included in a prospective, observational study (average age was 49.3 ± 12.7). All patients were determined the blood lipid spectrum and IL-10, TNF-a, MCP-1 levels in peritoneal dialysis effluent (PDE). PD adequacy indicators evaluated by determining the concentration of urea and creatinine in plasma, urine and dialysate, calculated weekly creatinine clearance (CrCl), dialysis (Kt/ Vd), renal (Kt/ Vr) and total weekly urea clearance (Kt/ V).&#x0D; Results. Dyslipidemia defined as increase of atherogenic lipoprotein fractions and inhibition ofHDL cholesterol was identified in 70% of the PD-patients. LDL cholesterol level and, accordingly, an atherogenic index (AI) were significantly dependent on the duration of PD treatment (R2 = 2.18 ± 0.15 (95% CI 1.87, 2.5), p &lt; 0,0001 and R2 = 2.77 ± 0.27(95% CI 2.2, 3.3), p &lt; 0,0001). The blood levels of total cholesterol, LDL-C and TG in the patients with diabetes were significantly higher compared with the diabetes-free patients (p = 0.007, p = 0.001 andp = 0.02, respectively).&#x0D; Reducing the HDL cholesterol level was associated with high intraperitoneal production of pro-inflammatory mediators TNF-a (r = - 0.53;p = 0.001) and anti-inflammatory IL-10 (r = - 0.783;p &lt;0.0001), whereas hypertriglyceridemia and high VLDL cholesterol are associated with an increase of MCP-1 (r = 0.6;p = 0.0003 and r = 0.55;p = 0.002, respectively).&#x0D; The Cox proportional hazards regression analysis demonstrated the significant effect of VLDL cholesterol, LDL cholesterol and AI on the survival of PD technique survival (x2 = 24.8; p &lt; 0.0001). The results of the Kaplan–Meier analysis and log-rank test also identified that there was a significant difference in the cumulative technical survival rate between the patients with AI level &lt; 3.5 and &gt; 3.5 (log-rank test: x2 = 19.8, P = 0.001.&#x0D; Conclusions. Our results can be considered dyslipidemia in PD-patients not only as a traditional risk factor for CVD, but also as a predictor of chronic intraperitoneal inflammation and decrease of PD technical survival.

Sustained low peritoneal effluent CCL18 levels are associated with preservation of peritoneal membrane function in peritoneal dialysis.

Peritoneal membrane failure (PMF) and, ultimately, encapsulating peritoneal sclerosis (EPS) are the most serious peritoneal dialysis (PD) complications. Combining clinical and peritoneal transport data with the measurement of molecular biomarkers, such as the chemokine CCL18, would improve the complex diagnosis and management of PMF. We measured CCL18 levels in 43 patients’ effluent and serum at baseline and after 1, 2, and 3 years of PD treatment by retrospective longitudinal study, and evaluated their association with PMF/EPS development and peritoneal risk factors. To confirm the trends observed in the longitudinal study, a cross-sectional study was performed on 61 isolated samples from long-term (more than 3 years) patients treated with PD. We observed that the patients with no membrane dysfunction showed sustained low CCL18 levels in peritoneal effluent over time. An increase in CCL18 levels at any time was predictive of PMF development (final CCL18 increase over baseline, p = .014; and maximum CCL18 increase, p = .039). At year 3 of PD, CCL18 values in effluent under 3.15 ng/ml showed an 89.5% negative predictive value, and higher levels were associated with later PMF (odds ratio 4.3; 95% CI 0.90–20.89; p = .067). Moreover, CCL18 levels in effluent at year 3 of PD were independently associated with a risk of PMF development, adjusted for the classical (water and creatinine) peritoneal transport parameters. These trends were confirmed in a cross-sectional study of 61 long-term patients treated with PD. In conclusion, our study shows the diagnostic capacity of chemokine CCL18 levels in peritoneal effluent to predict PMF and suggests CCL18 as a new marker and mediator of this serious condition as well as a new potential therapeutic target.

Unusual Listeria monocytogenes peritonitis in peritoneal dialysis patient with liver cirrhosis: a case report and review of literature.

Spontaneous Listeria peritonitis is well described in liver failure, but is uncommon in peritoneal dialysis patients. Atypical cases where peritonitis symptoms develop after systemic manifestations are rare and challenging for diagnostic. A 57-year-old peritoneal dialysis patient with history of ethylic cirrhosis was admitted after epileptic seizure. On admission, patient was soporous without signs of peritonitis and meningitis. Patient's peritoneal effluent was clear, with normal leukocytes. Cranial CT scan showed no abnormalities. Laboratory exams revealed positive inflammatory syndrome. Despite antibiotic therapy, next day, symptoms aggravated with coma development. Peritoneal effluent became cloudy and its leukocyte count rose up. Effluent microscopy revealed Gram-positive bacilli. Patient was started with intraperitoneal Vancomycin and Amikacin. Patient's clinical condition deteriorated with lethal outcome. Post-mortem analysis of effluent and blood culture showed growth of L. monocytogenes. Apart from idiopathic etiology, goat-milk curd, that patient had started consuming 10days before admission, could theoretically be considered as possible infection vehicle. L. monocytogenes peritonitis in peritoneal dialysis patients is rare, but must be considered in immunocompromised or patients with concomitant liver failure, especially after Gram-positive bacilli identification in peritoneal effluent. In case of suspiscion of Listeria peritonitis, Ampicillin should be initiated, because bacteria often poorly respond to currently recommended empiric regimens.

Machine-learning algorithms define pathogen-specific local immune fingerprints in peritoneal dialysis patients with bacterial infections

The immune system has evolved to sense invading pathogens, control infection, and restore tissue integrity. Despite symptomatic variability in patients, unequivocal evidence that an individual's immune system distinguishes between different organisms and mounts an appropriate response is lacking. We here used a systematic approach to characterize responses to microbiologically well-defined infection in a total of 83 peritoneal dialysis patients on the day of presentation with acute peritonitis. A broad range of cellular and soluble parameters was determined in peritoneal effluents, covering the majority of local immune cells, inflammatory and regulatory cytokines and chemokines as well as tissue damage–related factors. Our analyses, utilizing machine-learning algorithms, demonstrate that different groups of bacteria induce qualitatively distinct local immune fingerprints, with specific biomarker signatures associated with Gram-negative and Gram-positive organisms, and with culture-negative episodes of unclear etiology. Even more, within the Gram-positive group, unique immune biomarker combinations identified streptococcal and non-streptococcal species including coagulase-negative Staphylococcus spp. These findings have diagnostic and prognostic implications by informing patient management and treatment choice at the point of care. Thus, our data establish the power of non-linear mathematical models to analyze complex biomedical datasets and highlight key pathways involved in pathogen-specific immune responses.

Detection of human immunodeficiency virus-1 ribonucleic acid in the peritoneal effluent of renal failure patients on highly active antiretroviral therapy.

We evaluated the shedding of human immunodeficiency virus (HIV)-1 particles into continuous ambulatory peritoneal dialysis (CAPD) effluents of HIV-positive patients with end-stage renal disease (ESRD). A total of 58 HIV-positive patients with ESRD on highly active antiretroviral therapy (HAART) who had Tenckhoff catheters inserted between September 2012 and February 2015 were prospectively reviewed and followed for 18 months. Peritoneal dialysis (PD) effluent samples from functioning CAPD catheters and plasma samples were obtained at three points during regular clinic visits on days 45 ± 37, 200 ± 19 and 377 ± 13 after catheter insertion. All specimens were stored at -20°C, and each batch was analysed by Roche quantitative HIV-1 polymerase chain reaction assay to detect HIV-1 particles. Clustered logistic regression was used to test for independent predictors of HIV-1 detection in CAPD effluents. HIV-1 RNA above 20 copies/mL assay limit was detectable in 19% (first batch), 26.3% (second batch) and 20% (third batch) of PD effluent specimens. HIV-1 RNA was detectable in PD fluid, without corresponding detection in the paired plasma in 3.4% (first batch), 5.3% (second batch) and 10% (third batch) of samples. Detection of HIV-1 in plasma sample (odds ratios 3.94; 95% confidence interval 1.14-13.55; P = 0.030), body mass index, serum albumin and HAART regimen were found to be significantly associated with HIV-1 detection in PD effluents. HIV particles are shed in detectable amounts into CAPD effluents even in patients with suppressed plasma viral load, raising concerns of a localized sanctuary site and potential infectivity of HIV-positive CAPD patients on a full complement of HAART.

Sclerosing Encapsulating Peritonitis in A Peritoneal Dialysis Patient

Clinical Image A 56-year-old male presented with abdominal pain, vomiting and peritoneal irritation signs on physical examination. He had history of IgA nephropathy in peritoneal dialysis since fourteen years ago with multiple episodes of bacterial peritonitis responding to intraperitoneal antibiotics. Void residual urine output. His peritoneal permeability was high requiring automated peritoneal dialysis with elevated glucose load for appropriate volume overload management. He refused hemodialysis repeatedly. In the last year the patient reported anorexia, weight loss and several minor episodes of abdominal pain accompanied by constipation or diarrhea that were blamed on a known diverticular disease. In admission the peritoneal effluent was clear. A CT of abdomen showed diffuse thickening of the peritoneum with linear calcifications and bands of fibrosis that were arranged between the loops of small intestine and forming several compartments which were confined. The laparotomy showed a peritoneum of “carapacelike” appearance (Figure 1), brownish, with a thick fibrous cover that included all intestinal loops (Figures 2 and 3) suggestive of abdominal cocoon due to a sclerosing encapsulating peritonitis. Treatment with adhesiolysis, antibiotics, parenteral nutrition, tamoxifen and hemodialysis was unsuccessful; patient died ten days later because of septic shock.