Preventing peritoneal membrane fibrosis in peritoneal dialysis patients.

Long-term peritoneal dialysis causes morphologic and functional changes in the peritoneal membrane. Although mesothelial-mesenchymal transition of peritoneal mesothelial cells is a key process leading to peritoneal fibrosis, and bioincompatible peritoneal dialysis solutions (glucose, glucose degradation products, and advanced glycation end products or a combination) are responsible for altering mesothelial cell function and proliferation, mechanisms underlying these processes remain largely unclear. Peritoneal fibrosis has 2 cooperative parts, the fibrosis process itself and the inflammation. The link between these 2 processes is frequently bidirectional, with each one inducing the other. This review outlines our current understanding about the definition and pathophysiology of peritoneal fibrosis, recent studies on key fibrogenic molecular machinery in peritoneal fibrosis, such as the role of transforming growth factor-ß/Smads, transforming growth factor-ß ß/Smad independent pathways, and noncoding RNAs. The diagnosis of peritoneal fibrosis, including effluent biomarkers and the histopathology of a peritoneal biopsy, which is the gold standard for demonstrating peritoneal fibrosis, is introduced in detail. Several interventions for peritoneal fibrosis based on biomarkers, cytology, histology, functional studies, and antagonists are presented in this review. Recent experimental trials in animal models, including pharmacology and gene therapy, which could offer novel insights into the treatment of peritoneal fibrosis in the near future, are also discussed in depth.

Evaluation of peritoneal CEA levels following colorectal cancer surgery.

BACKGROUND: Peritoneal carcinoembryonic antigen (pCEA) levels in the early postoperative period following a curative resection of colorectal cancer (CRC) have not been previously studied. METHODS: Postoperative peritoneal fluids of 36 CRC patients followed by 24 benign colonic disease patients were evaluated for CEA levels and tumor cell presence. Serum CEA levels were also evaluated prior and after surgery. RESULTS: Although high postoperative pCEA levels were observed in some benign patients, more CRC patients exhibited significant elevation of postoperative pCEA (>5 ng/ml) compared to benign patients (50% vs. 23%, P = 0.039). Postoperative median pCEA levels of CRC patients were significantly higher compared to benign patients (5.4 vs. 2 ng/ml, P = 0.011). Specifically, pCEA levels in CRC patients were significantly elevated when measured during the first 24 hr after surgery. Postoperative pCEA levels were associated with colon tumor location compared to rectal location. However, no correlation was found with known risk factors for cancer recurrence or with serum CEA levels. CONCLUSIONS: Postoperative pCEA levels may be significantly elevated following a curative resection for CRC. Its significance within patient's prognostic evaluation remains to be studied. Inclusion of patient's follow-up data may reveal the significance of elevated pCEA levels following CRC resection.

Antimicrobial Susceptibility Profile of Several Bacteria Species Identified in the Peritoneal Exudate of Cows Affected by Parietal Fibrinous Peritonitis after Caesarean Section.

The aim of this study was to identify the species and antimicrobial susceptibility of bacteria involved in parietal fibrinous peritonitis (PFP). We studied 156 peritoneal fluid samples from cows presenting PFP after caesarean section. Bacteria were cultured in selective media and their antimicrobial susceptibility was tested by disk diffusion assay. Bacteria were isolated in the majority (129/156; 83%) of samples. The majority (82/129; 63%) of positive samples contained one dominant species, while two or more species were cultured in 47/129 (36%) samples. Trueperella pyogenes (T. Pyogenes) (107 strains) was the most identified species, followed by Escherichia coli (E. coli) (38 strains), Proteus mirabilis (P. mirabilis) (6 strains), and Clostridium perfringens (C. perfringens) (6 strains). Several other species were sporadically identified. Antimicrobial susceptibility was tested in 59/185 strains, predominantly E. coli (38 strains) and P. mirabilis (6 strains). Antibiotic resistance, including resistance to molecules of critical importance, was commonly observed; strains were classified as weakly drug resistant (22/59; 37%), multidrug resistant (24/59; 41%), extensively drug resistant (12/59; 20%), or pan-drug resistant (1/59; 2%). In conclusion, extensive antibiotic resistance in the isolated germs might contribute to treatment failure. Ideally, antimicrobial therapy of PFP should be based upon bacterial culture and susceptibility testing.

Diagnosis and categorization of malignant effusions: A 6-year review from a single academic institution.

BACKGROUND: Cytologic detection of malignant cells in pleural, peritoneal, or pericardial effusion most likely indicates advanced stage of malignant disease. There are a few studies updating the categorization of malignant effusions. METHODS: The electronic pathology database was searched to identify consecutive cases of malignant effusion during a 6-year period. Patient age and gender, origins of known malignancy, and cytologic diagnoses were recorded and summarized. RESULTS: A total of 1059 specimens included 561 (53%) pleural, 441 (41.6%) peritoneal, and 57 (5.4%) pericardial fluids. Most of the pleural (516, 92.0%), peritoneal (418, 94.8%), and pericardial (53, 93.0%) specimens were derived from patients with a single known malignancy. More common origins involving pleural fluid were lung (152, 27.1%) followed by breast (103, 18.4%) and gastrointestinal tract (76, 13.5%). The most common etiology for women and men was breast (102, 30.8%) and lung (67, 36.2%), respectively. More common origins involving peritoneal fluid were gastrointestinal (158, 35.8%) and gynecologic (156, 35.4%) tracts, and breast (46, 10.4%). The most common etiology for women and men was Mullerian (156, 55.5%) and gastrointestinal tract (94, 68.6%), respectively. Most common origins involving the pericardial fluid were breast (20, 37.7%) and lung (17, 29.8%). Breast and lung were the most common etiology for women (20, 57.1%) and men (8, 44.4%), respectively. CONCLUSIONS: Breast and lung remain to be the most common origin of both malignant pleural and pericardial effusion for women and men, respectively. The most common origin involving peritoneal effusion is Mullerian for women and gastrointestinal tract for men.

Infectious Agents Identified by Real-Time PCR, Serology and Bacteriology in Blood and Peritoneal Exudate Samples of Cows Affected by Parietal Fibrinous Peritonitis after Caesarean Section.

The aim of this study was to identify the pathogens potentially involved in parietal fibrinous peritonitis (PFP). PFP is a complication of laparotomy in cattle, characterized by an accumulation of exudate inside a fibrinous capsule. We have studied 72 cases of PFP in Belgian blue cows, confirmed by a standard diagnostic protocol. Blood was collected to evaluate the presence of antibodies for Mycoplasma bovis(M. bovis), Coxiella burnetii(C. burnetii) and Bovine Herpesvirus 4(BoHV4) by enzyme-linked immunosorbent assays. Peritoneal exudate was obtained from the PFP cavity to perform bacteriological culture, and to identify the DNA of M. bovis, C. burnetii and BoHV4 using real time polymerase chain reaction (qPCR). Bacteriological culture was positive in most peritoneal samples (59/72); Trueperella pyogenes (T. pyogenes) (51/72) and Escherichia coli (E. coli) (20/72) were the most frequently identified. For BoHV4, the majority of cows showed positive serology and qPCR (56/72 and 49/72, respectively). Contrariwise, M. bovis (17/72 and 6/72, respectively) and C. burnetii (15/72 and 6/72, respectively) were less frequently detected (p < 0.0001). Our study proves that PFP can no longer be qualified as a sterile inflammation. Moreover, we herein describe the first identification of BoHV4 and C. burnetii in cows affected by PFP.

Comparison of benign peritoneal fluid- and ovarian cancer ascites-derived extracellular vesicle RNA biomarkers.

BACKGROUND: Extracellular vesicles (EVs) are considered as a new class of resources for potential biomarkers. We analyzed expression of specific mRNA and miRNA in EVs derived from ovarian cancer ascites and the ideal controls, peritoneal fluids from benign patients for potential early detection and prognostic biomarkers. METHODS: Fluids were collected from subjects with benign cysts or endometrioma (n = 10), or low/high grade serous ovarian carcinoma (n = 8). EV particles were captured using primarily ExoComplete filterplate or ultracentrifugation and analyzed by nanoparticle tracking analysis, ELISA, and scanning electron microscopy. EV RNAs extracted from two ascites and three peritoneal fluids were submitted for next-generation sequencing. The expression of 34 mRNA and 18 miRNAs in the EVs isolated from patient fluids and cell line media was determined using qPCR. RESULTS: EVs isolated from patient samples had concentrations greater than 1010 EV particles/mL and 30% were EpCAM-positive based on ELISA. EV particle sizes averaged 113 ± 11.5 nm. The qPCR studies identified five mRNA (CA11, MEDAG, LAMA4, SPINT2, NANOG) and six miRNA (let-7b, miR23b, miR29a, miR30d, miR205, miR720) that were significantly differentially expressed between cancer ascites and peritoneal fluids. In addition, CA11 mRNA was decreased to 0.5-fold and SPINT2 and NANOG mRNA were significantly increased up to 100-fold in conditioned media of cancer cells compared to immortalized ovarian surface and fallopian tube epithelial cell lines, the hypothesized cells of origin for ovarian cancer development. CONCLUSIONS: This study indicates that EV mRNA profiles can reflect the disease stage and may provide a potentially novel source for discovery of biomarkers in ovarian cancer.

Pharmacovigilance as a tool for safety and monitoring: a review of general issues and the specific challenges with end-stage renal failure patients.

Pharmacovigilance is instrumental in helping to ensure patient safety for both newly released drugs and those that are well established in the market. However, while pharmacovigilance procedures are strictly regulated in the clinical trial setting, post-marketing adverse event reporting is not well implemented or enforced. As such, the underreporting of adverse events, in relation to drugs that are on the market, is estimated to be in the region of 90%. The identification of drug safety issues in patients with complex diseases and extensive comorbidities is therefore particularly challenging. Dialysis patients - those with end-stage renal disease and often other comorbidities such as diabetes, hypertension, and cardiovascular disease - are a population with significant treatment challenges. Patients receive dialysis using complex medical devices (eg, a peritoneal dialysis home cycler) and also receive a range of pharmaceutical agents as part of dialysis itself (eg, peritoneal dialysis solutions). Many of the pharmaceutical agents used to treat these patients have been developed in populations without these complications and, therefore, an extensive knowledge of potential problems and contraindications in the dialysis population is lacking. It is important that the nephrology community understands the concept of pharmacovigilance - the pharmacologic science relating to the detection, assessment, understanding, and prevention of adverse effects, particularly long-term and short-term side effects, of medicines. Health care professionals (HCPs) and providers, pharmaceutical companies, global regulatory agencies, and the patients themselves all play unique and critical roles in this process. This review defines the science of pharmacovigilance and the process of adverse event reporting, highlights the new directions that pharmacovigilance has taken, and provides insight for HCPs managing dialysis patients into the important role that they play in helping to shape the understanding of a drug's safety profile in order to continually enhance patient safety.