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Query: UMLS:C0031154 (peritonitis)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vancomycin is a useful antimicrobial agent in patients undergoing chronic hemodialysis treatment; its efficacy in chronic peritoneal dialysis (CPD) has not been established. Serum (VS) and peritoneal fluid (VPF) vancomycin concentrations were measured in two CPD patients with staphylococcal peritonitis. Half-life of VS agreed with the half-life of VPF in each patient, and the VS/VPF ratio was 1.27 in both patients. Distribution volumes were 37.2 and 58.7 l, values approximating total body water in these patients. VS and VPF persisted in the therapeutic range (greater than 5 microgram/ml) for more than 16 days. In one patient, mean peritoneal clearacne was 9.8 ml/min, and overall drug clearance averaged 2.3 ml/min; in the other patient, overall clearance was 2.1 ml/min. These results indicate that therapeutic vancomycin levels can be maintained for more than 16 days with a single 1 g intravenous dose in patients receiving intermittent CPD, as is the case for hemodialysis patients. Because of this, parenteral vancomycin is useful in the treatment of staphylococcal peritonitis in CPD patients.
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PMID:Peritoneal clearance and total body elimination of vancomycin during chronic intermittent peritoneal dialysis. 43 39

The traditional and most frequently employed surgical approach to perforated necrotizing enterocolitis (NEC), laparotomy and bowel resection with enterostomy creation, has been associated with an unacceptably high mortality and major morbidity (sepsis, short-gut syndrome, strictures, long-term total parenteral nutrition (TPN), prolonged and costly hospitalizations with multiple operations, the inevitable open-and-close procedure for "hopeless" extensive gut ischemia in approximately 10% of laparotomy cases, etc.). The use of the laparotomy "patch, drain, and wait" (PD&W) approach to this serious of NEC complication has provided a simple, direct, and effective means of dealing with this problem. The basic principle is to resect no gut and do no enterostomies. The details are presented here as well as the multiple types of "patching" and the importance of use of extensive direct-vision draining with bilateral small Penrose drains from the undersurfaces of both diaphragms into the pelvis with exit sites in both lower quadrants. Proper and effective patching and draining cannot be done blindly,but requires direct vision (laparotomy or laparoscopy). The critical components and timing of the "waiting" are emphasized, including the vital importance of strict avoidance of early post-drainage laparotomy in the 7- to 14-day post-drainage period (whether the drainage is percutaneous, laparotomy PD&W, or laparoscopy PD&W) due to the early, life-threatening-ending hypervascularity that occurs at this time and if left unmolested will function beneficially as life- and gut-saving "good angiogenesis". The bilateral Penrose drains capture fecal fistulas and function quite well as de-facto enterostomies as the peritoneal cavity is rapidly obliterated by adhesions and massive, florid hypervascularity/gut hypoxia triggered "good angiogenesis" (no peritoneal cavity, no peritonitis). Broad-spectrum triple antibiotics and the routine use of TPN contribute to favorable results. The lessons/experiments of nature encountered in newborns with midgut atresia(s) and remarkable levels of gut survival, in the occasional case with only meconium peritonitis and no obstruction ("auto-anastomosis") are pertinent here as the TPN of PD&W is provided in atresia(s) by the maternal-placental circulation and the sterile peritoneal cavity of atresia(s) is simulated by the combination of antibiotics and peritoneal-cavity obliteration. Life- and gut-saving "good angiogenesis" is common to both situations. A 15-year personal experience with the PD&W laparotomy approach to perforated NEC in 23 cases is reported here with no mortality in the initial 60 postoperative days, no major morbidity, and no second operation required in 70% (spontaneous "auto-anastomosis") of cases. All infants with extensive gut ischemia/necrosis (NEC totalis) who would otherwise be classified as "hopeless" and managed by open-and-close only were managed in this experience successfully by PD&W with preservation of both life and an adequate amount of gut, although a second operation was required in these cases to re-establish intestinal continuity. A particularly striking observation was the rapid transition of these infants from profound illness to near-normalcy in a matter of hours after the initiation of PD&W--much like the rapid clinical changes accompanying the lancing of a boil or an abscess. An involvement of hypoxia-induced "good angiogenesis" with marked hypervascularity and involving molecules, genes, and receptors of the vascular endothelial growth factor family of hypoxia-induced angiogenesis molecules is speculated upon, and clinical studies to document these speculations are suggested as well as studies evaluating the potential of laparoscopic PD&W. The usefulness of Argyle chest-tube "venting" and "stenting" by trans-anal passage above colonic "patched" areas as seen in 2 cases is worthy of further study and use.
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PMID:Successful use of the "patch, drain, and wait" laparotomy approach to perforated necrotizing enterocolitis: is hypoxia-triggered "good angiogenesis" involved? 1095 62

Diabetic nephropathy is the leading cause of end-stage renal disease worldwide. Although death rates of diabetic patients on hemodialysis and peritoneal dialysis (PD) have decreased substantially, they remain higher than rates in nondiabetics on both modalities. PD offers equal or better survival than hemodialysis for younger diabetic patients during early years of dialysis. PD technique survival does not appear different between diabetic and nondiabetic patients but is inferior to hemodialysis technique survival. PD may accelerate changes in peritoneal membrane structure and function in diabetics. Peritonitis and conventional PD solutions containing high glucose and glucose degradation products are implicated in PD technique failure. Increased peritoneal expression of vascular endothelial growth factor and transforming growth factor-beta1 and excessive accumulation of advanced glycosylation end products may be involved in the progressive increase in membrane permeability, loss of ultrafiltration, and peritoneal fibrosis. Nonglucose PD solutions or solutions containing low glucose degradation products may prevent or delay alterations in peritoneal membrane structure and function in diabetic as well as nondiabetic patients during long-term PD.
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PMID:Peritoneal dialysis in diabetic patients. 1157 55

Peritonitis carcinomatosa, indicating the presence of malignant cells in the peritoneal cavity, is a well-known complication of malignant disease. As a result, so-called malignant ascites develops. Malignant ascites is a debilitating condition for which no effective anti-tumor therapy is available. Frequent draining may be necessary to relieve pain and discomfort. Most studies regarding malignant ascites focus on diagnosis and treatment. In this paper. we will address the subject from a pathophysiologic perspective, using the characteristics of malignant ascites, Starling's equation of capillary forces, and recent knowledge regarding biologically active peptides produced by tumor cells. Following this approach. apart from decreased lymphatic ascites absorption, increased net capillary fluid-production can be identified as a contributing feature of ascites formation. The increased net filtration is due to an increase of overall capillary membrane-surface, increased capillary permeability and a subsequent increase of intraperitoneal protein concentration leading to increased intraperitoneal oncotic pressure. This sequence might be the result of biologically active peptides produced by tumor cells such as vascular endothelial growth factor and basic fibroblast growth factor. Interference with these mediators may serve as a target in future therapeutic strategies.
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PMID:Pathogenesis of malignant ascites: Starling's law of capillary hemodynamics revisited. 1176 4

Peritonitis, a common complication of peritoneal dialysis, is followed by acute changes in the function of the peritoneum. The role of inflammatory cytokines in these processes is not clearly identified. We used adenoviral-mediated gene transfer to transiently overexpress interleukin (IL)-1 beta (AdIL-1 beta) or tumor necrosis factor (TNF)-alpha (AdTNF-alpha) in the rat peritoneum then used a modified equilibrium test to study the histological and functional changes. Overexpression of IL-1 beta or TNF-alpha led to an acute inflammatory response. Both inflammatory cytokines induced an early expression of the angiogenic cytokine, vascular endothelial growth factor, along with increased expression of the profibrotic cytokine, transforming growth factor-beta1, along with fibronectin expression and collagen deposition in peritoneal tissues. Both inflammatory cytokines induced angiogenesis, increased solute permeability, and ultrafiltration dysfunction at earlier time points. Changes in structure and function seen in AdTNF-alpha-treated animals returned to normal by 21 days after infection, whereas AdIL-1 beta-treated animals had persistently increased vasculature with submesothelial thickening and fibrosis. This was associated with up-regulation TIMP-1. TNF-alpha or IL-1 beta both induce acute changes in the peritoneum that mimic those seen in peritoneal dialysis patients who experience an episode of peritonitis. These functional changes were associated with early angiogenesis that resolved rapidly after exposure to TNF-alpha. IL-1 beta exposure, however, led to a different response with sustained vascularization and fibrosis. IL-1 beta inhibition may be a therapeutic goal in acute peritonitis to prevent peritoneal damage.
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PMID:Inflammatory cytokines, angiogenesis, and fibrosis in the rat peritoneum. 1205 31

This paper reviews some important recent findings on the molecular biology of the peritoneal membrane. It attempts to correlate in vitro and in vivo experimental results with the possible clinical consequences. The most common functional alteration during long-term CAPD is increased peritoneal small-solute transport rate, resulting in impaired ultrafiltration and decreased dialysis efficiency. This contribution first discusses the most relevant advances in the biochemistry and molecular biology of the peritoneal membrane following peritonitis and as consequence of the continuous exposure to unphysiological dialysis fluids. In a second part the preliminary experimental and clinical experience with more biocompatible fluids is summarized. The most relevant structural and functional alterations of the membrane following repeated peritonitis is the consequence of the response of the peritoneum to infective organisms involving the inflammatory cytokines and the interaction between membrane resident cell populations: macrophages, mesothelial cells and fibroblasts. In this setting, human biopsy studies and animal experiments have identified an increase in the peritoneal-associated vasculature, which seems to be the primary cause of increased solute transport. The structural and functional alterations in the membrane in long-term peritoneal dialysis are thought to be the consequence of the toxicity of glucose, either directly or indirectly through the generation of glucose degradation products or the formation of advanced glycation end-products. In particular, an important role for vascular endothelial growth factor and nitric oxide as downstream mediators of the alterations has been suggested. Finally, the last part of this paper reviews the actual and future research aimed at an amelioration of the biocompatibility of the dialysis fluids. Replacing glucose by other osmotic agents, changing the sterilization process, replacing the lactate buffer by bicarbonate, blocking the formation of reactive carbonyl products and of the neoangiogenesis are the most promising changes to enhance the biocompatibility. Finally, gene therapy may in the future have an important contribution. Ex vivo gene therapy involves harvesting peritoneum samples to isolate mesothelial cells that will be genetically modified before re-implantation into the peritoneal cavity.
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PMID:Recent concepts in the molecular biology of the peritoneal membrane - implications for more biocompatible dialysis solutions. 1256 56

We examined the expression of four angiogenesis factors (vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), platelet-derived endothelial cell growth factor (PD-ECGF) and basic fibroblast growth factor (bFGF)) in five human ovarian cancer cell lines by Northern blot analysis and immunohistochemical staining. The cancer cells were grown as a subconfluent monolayer culture, a multicellular aggregate (spheroid) in a three-dimensional culture, and a nude mouse-transplanted subcutaneous tumor in order to simulate the cellular conditions of ovarian cancers in peritonitis carcinomatosa, i.e. floating single tumor cells, multicellular aggregates and peritoneally implanted tumors. In each cell line, the expression of VEGF was detected in a monolayer culture and obviously enhanced in a three-dimensional culture. IL-8 was expressed in two of five cultured cell lines, but neither PD-ECGF nor bFGF was detected. Each cell line-derived transplanted tumor expressed immunohistochemical products of the four angiogenesis factors examined. These observations were confirmed by surgical specimens and suggested that ovarian cancer cells expressed different kinds and/or doses of angiogenesis factors depending on the form of the changed tumor cells during peritoneal implant formation.
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PMID:Expression of angiogenesis factors in monolayer culture, multicellular spheroid and in vivo transplanted tumor by human ovarian cancer cell lines. 1286 Feb 81

Long-term continuous ambulatory peritoneal dialysis (CAPD) often causes peritoneal fibrosis and sclerosis with a loss of function, and some CAPD patients develop sclerosing encapsulating peritonitis. Glucose-based peritoneal dialysis fluids readily produce glucose degradation products by heat sterilization, and glucose degradation products accelerate the formation of advanced glycation end-products (AGE) in the peritoneal cavity. The accumulation of AGE is observed in peritoneal mesothelial and submesothelial layers in CAPD patients, accompanied by enhanced expression of various growth factors and peritoneal thickening. The expression of transforming growth factor-beta1 (TGF-beta1), macrophage-colony stimulating factor, and vascular endothelial growth factor (VEGF) is distributed in the peritoneum similarly to that of AGE. In CAPD patients with low ultrafiltration (UF) capacity, peritoneal membrane is thickened owing to an increase in the number of cells such as fibroblasts and macrophages and collagen in the submesothelial layer. AGE is detected in the fibroblasts and macrophages as well as degenerated collagen. These cells in the submucosal layer are almost positive for the receptor for AGE (RAGE) and uptake AGE. The intensity of AGE accumulation and the expression of growth factors are associated with the severity of UF impairment. In fact, the accumulation of AGE and the expression of growth factors are recognized most markedly in the peritoneum of CAPD patients with low UF and sclerosing encapsulating peritonitis. In conclusion, long-time CAPD with heat-sterilized peritoneal dialysis fluid promotes AGE accumulation in the peritoneal membrane and alteration in peritoneal cell function and dialysis quality, followed by peritoneal sclerosis, and, finally, sclerosing encapsulating peritonitis.
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PMID:Advanced glycation end-products and peritoneal sclerosis. 1549 Apr 20

Peritoneal fibrosis (or sclerosis) is a complication of peritoneal dialysis (PD) and includes a wide spectrum of peritoneal structural changes, ranging from mild inflammation to severe sclerosing peritonitis and encapsulating-sclerosing peritonitis. In parallel with fibrosis, the peritoneum shows a progressive increase in capillary number (angiogenesis) and vasculopathy, which are involved in both the elevation of small solute transport across the peritoneal membrane and ultrafiltration failure. The most important substances from the PD solutions responsible for peritoneal deterioration are glucose and glucose degradation products, which stimulate transforming growth factor (TGF)beta and vascular endothelial growth factor (VEGF) production by mesothelial cells (MCs). TGFbeta is a potent pro-fibrotic factor and induces epithelial-mesenchymal transition (EMT) of the MC. Local production of VEGF during PD appears to play a central role in the processes leading to peritoneal neo-angiogenesis and functional decline. This review discusses the mechanisms implicated in peritoneal structural alteration and points to EMT of MC as the protagonist and initiator of peritoneal membrane injury, through an increment of the submesothelial fibroblast population. We also propose possible mechanisms of regulation and new targets for inhibition of EMT.
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PMID:Epithelial to mesenchymal transition as a triggering factor of peritoneal membrane fibrosis and angiogenesis in peritoneal dialysis patients. 1581 2

The development of animal models in peritoneal dialysis has led to some breakthroughs in the application of this dialysis modality in clinical practice. These breakthroughs are (1) a better understanding of the physiology and pathophysiology of solute transport and ultrafiltration mechanisms, (2) the observation and integration of the long-term structural and functional alterations of the membrane, (3) a better understanding of the biocompatibility issues involved in PD, leading to the clinical introduction of more biocompatible dialysis solutions and finally, (4) the development of colloid osmotic solutions containing polyglucose polymers for application in the long dwells. Intravital miscroscopy provides information in live animals about diverse functional parameters, such as blood flow rate, vessel diameter, permeability to macromolecules, leukocyte-endothelium interaction, capillary recruitment, and lymph vessel kinetics. Also evaluation of different parameters in a living experimental animal, allowing integration of function and structure is possible. A variety of chronic PD models have been developed, mainly to study effects of long-term peritoneal dialysate exposure on peritoneal membrane function and structure. The implementation of different blocking agents of biochemical substances in these models has elucidated many molecular biological mechanisms involved in these processes. The important roles of aquaporins, vascular endothelial growth factor, nitric oxide, advanced glycation end product formation and their receptor (RAGE) upregulation and the integrated roles of all these factors in the fibrotic alterations of the membrane as observed in patients on long-term PD have been investigated. More recently, genetically modified mice have been used as an important tool to investigate the molecular basis of peritoneal changes during dialysis and during acute peritonitis.
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PMID:What did we learn from animal models in peritoneal dialysis? 1672 Sep 94


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