Review

Authors: Annalisa Capobianco, Lucia Cottone, Antonella Monno...

The peritoneum defines a confined microenvironment, which is stable under normal conditions, but is exposed to the damaging effect of infections, surgical injuries, and other neoplastic and non-neoplastic events. Its response to damage includes the recruitment, proliferation, and activation of a variety of haematopoietic and stromal cells. In physiological conditions, effective responses to injuries are organized; inflammatory triggers are eliminated; inflammation quickly abates; and the normal tissue architecture is restored. However, if inflammatory triggers are not cleared, fibrosis or scarring occurs and impaired tissue function ultimately leads to organ failure. Autoimmune serositis is characterized by the persistence of self-antigens and a relapsing clinical pattern. Peritoneal carcinomatosis and endometriosis are characterized by the persistence of cancer cells or ectopic endometrial cells in the peritoneal cavity. Some of the molecular signals orchestrating the recruitment of inflammatory cells in the peritoneum have been identified in the last few years. Alternative activation of peritoneal macrophages was shown to guide angiogenesis and fibrosis, and could represent a novel target for molecular intervention. This review summarizes current knowledge of the alterations to the immune response in the peritoneal environment, highlighting the ambiguous role played by persistently activated reparative macrophages in the pathogenesis of common human diseases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Topics: Autoimmune Diseases; Endometriosis; Female; Humans; Immunity, Cellular; Peritoneal Diseases; Peritoneal Fibrosis; Peritoneal Neoplasms; Peritoneum; Peritonitis; Serositis; Wound Healing

PubMed: 28722107
DOI: 10.1002/path.4942

Review

Authors: Christopher J Danford, Steven C Lin, Martin P Smith...

Encapsulating peritoneal sclerosis (EPS) is a debilitating condition characterized by a fibrocollagenous membrane encasing the small intestine, resulting in recurrent small bowel obstructions. EPS is most commonly associated with long-term peritoneal dialysis, though medications, peritoneal infection, and systemic inflammatory disorders have been implicated. Many cases remain idiopathic. Diagnosis is often delayed given the rarity of the disorder combined with non-specific symptoms and laboratory findings. Although cross-sectional imaging with computed tomography of the abdomen can be suggestive of the disorder, many patients undergo exploratory laparotomy for diagnosis. Mortality approaches 50% one year after diagnosis. Treatment for EPS involves treating the underlying condition or eliminating possible inciting agents (. peritoneal dialysis, medications, infections) and nutritional support, frequently with total parenteral nutrition. EPS-specific treatment depends on the disease stage. In the inflammatory stage, corticosteroids are the treatment of choice, while in the fibrotic stage, tamoxifen may be beneficial. In practice, distinguishing between stages may be difficult and both may be used. Surgical intervention, consisting of peritonectomy and enterolysis, is time-consuming and high-risk and is reserved for situations in which conservative medical therapy fails in institutions with surgical expertise in this area. Herein we review the available literature of the etiology, pathogenesis, diagnosis, and treatment of this rare, but potentially devastating disease.

Topics: Glucocorticoids; Humans; Intestinal Obstruction; Intestine, Small; Parenteral Nutrition, Total; Peritoneal Dialysis; Peritoneal Fibrosis; Peritoneum; Peritonitis; Recurrence; Sclerosis; Tamoxifen; Tomography, X-Ray Computed; Treatment Outcome

PubMed: 30065556
DOI: 10.3748/wjg.v24.i28.3101

Authors: Adrian Fischer, Juliane Wannemacher, Simon Christ...

Internal organs heal injuries with new connective tissue, but the cellular and molecular events of this process remain obscure. By tagging extracellular matrix around the mesothelium lining in mouse peritoneum, liver and cecum, here we show that preexisting matrix was transferred across organs into wounds in various injury models. Using proteomics, genetic lineage-tracing and selective injury in juxtaposed organs, we found that the tissue of origin for the transferred matrix likely dictated the scarring or regeneration of the healing tissue. Single-cell RNA sequencing and genetic and chemical screens indicated that the preexisting matrix was transferred by neutrophils dependent on the HSF-integrin AM/B2-kindlin3 cascade. Pharmacologic inhibition of this axis prevented matrix transfer and the formation of peritoneal adhesions. Matrix transfer was thus an early event of wound repair and provides a therapeutic window to dampen scaring across a range of conditions.

Topics: Animals; Epithelium; Extracellular Matrix; Mice; Neutrophils; Peritoneum; Wound Healing

PubMed: 35354953
DOI: 10.1038/s41590-022-01166-6

Review

Authors: Johann Morelle, Mark Lambie, Carl M Öberg...

A healthy and functional peritoneal membrane is key to achieving sufficient ultrafiltration and restoring fluid balance, a major component of high-quality prescription in patients treated with peritoneal dialysis (PD). Variability in membrane function at the start of PD or changes over time on treatment influence dialysis prescription and outcomes, and dysfunction of the peritoneal membrane contributes to fluid overload and associated complications. In this review, we summarize the current knowledge about the structure, function, and pathophysiology of the peritoneal membrane with a focus on clinical implications for patient-centered care. We also discuss the molecular and genetic mechanisms of solute and water transport across the peritoneal membrane, including the role of aquaporin water channels in crystalloid versus colloid osmosis; why and how to assess membrane function using peritoneal equilibration tests; the etiologies of membrane dysfunction and their specific management; and the effect of genetic variation on membrane function and outcomes in patients treated with PD. This review also identifies the gaps in current knowledge and perspectives for future research to improve our understanding of the peritoneal membrane and, ultimately, the care of patients treated with PD.

Topics: Humans; Peritoneal Dialysis; Peritoneum; Water-Electrolyte Balance

PubMed: 37616463
DOI: 10.2215/CJN.0000000000000282

Review

Authors: Joanna Witkowicz

Mesothelial cells are an integral part of the peritoneum and play an important role in maintaining its structural and functional properties. In the recent years a number of studies on mesothelial cells have been performed to evaluate the localization, secretional properties and the ability of regeneration and transdifferentiation of these cells. They are also involved in the repair of the peritoneum damage following surgery or peritonitis. Mesothelial cells produce several cytokines, growth factors and extracellular matrix components, possessing anti-inflammatory and immunomodulatory properties. Because of their plasticity, these cells are able to form a new cell type like fibroblast, endothelial and smooth muscle cell, chondrocyte, osteoblast, adipocyte or neuron. The first step involves mesothelial cell transdifferentiation into progenitor cells with the capacity of further differentiation. In this paper the current knowledge concerning the mesothelial cell differentiation and transplantation has been reviewed. Own mesothelial cells of a patient are used in transplantation. They are sampled, cultured in vitro and then they can be used in the prevention and treatment of post-operative abdominal adhesions, incisional hernias, repair of peritoneal membrane of patients on long-term peritoneal dialysis, the prevention of ischemic myocardial damage, nerve regeneration and genetically modified recombinant protein secretion. Inevitably, more potential applications of transplanted mesothelial cell will be available over the next few years.

Topics: Epithelial Cells; Humans; Peritoneum

PubMed: 18619182
DOI: No ID Found

Authors: Koh Okamoto, Shuji Hatakeyama

Topics: Abdominal Pain; Adenosine Deaminase; Ascites; Ascitic Fluid; Biopsy; Humans; Mycobacterium tuberculosis; Omentum; Peritoneum; Peritonitis, Tuberculous; Tomography, X-Ray Computed; Young Adult

PubMed: 30231225
DOI: 10.1056/NEJMicm1713168

Review

Authors: Gaetano Piccolo, Matteo Barabino, Guglielmo Niccolò Piozzi...

Gallbladder cancer (GBC) is a rare disease with a poor prognosis. Simple cholecystectomy may be an adequate treatment only for very early disease (Tis, T1a), whereas reoperation is recommended for more advanced disease (T1b and T2). Radical cholecystectomy should have two fundamental objectives: To radically resect the liver parenchyma and to achieve adequate clearance of the lymph nodes. However, recent studies have shown that compared with lymph node dissection alone, liver resection does not improve survival outcomes. The oncological roles of lymphadenectomy and liver resection is distinct. Therefore, for patients with incidental GBC without liver invasion, hepatic resection is not always mandatory.

Topics: Humans; Cholecystectomy; Gallbladder Neoplasms; Hepatectomy; Incidental Findings; Liver; Lymph Node Excision; Lymphatic Metastasis; Neoplasm Staging; Peritoneum; Treatment Outcome

PubMed: 39221070
DOI: 10.3748/wjg.v30.i32.3739

Review

Authors: Mario Bonomini, Francesc E Borras, Maribel Troya-Saborido...

Peritoneal dialysis (PD) is an established home care, cost-effective renal replacement therapy (RRT), which offers several advantages over the most used dialysis modality, hemodialysis. Despite its potential benefits, however, PD is an under-prescribed method of treating uremic patients. Infectious complications (primarily peritonitis) and bio-incompatibility of PD solutions are the main contributors to PD drop-out, due to their potential for altering the functional and anatomical integrity of the peritoneal membrane. To improve the clinical outcome of PD, there is a need for biomarkers to identify patients at risk of PD-related complications and to guide personalized interventions. Several recent studies have shown that proteomic investigation may be a powerful tool in the prediction, early diagnosis, prognostic assessment, and therapeutic monitoring of patients on PD. Indeed, analysis of the proteome present in PD effluent has uncovered several proteins involved in inflammation and pro-fibrotic insult, in encapsulating peritoneal sclerosis, or even in detecting early changes before any measurable modifications occur in the traditional clinical parameters used to evaluate PD efficacy. We here review the proteomic studies conducted thus far, addressing the potential use of such omics methodology in identifying potential new biomarkers of the peritoneal membrane welfare in relation to dialytic prescription and adequacy.

Topics: Biomarkers; Humans; Peritoneal Dialysis; Peritoneum; Peritonitis; Prognosis; Proteome; Proteomics; Renal Dialysis

PubMed: 32752018
DOI: 10.3390/ijms21155489

Review

Authors: Sarah E Herrick, Bettina Wilm

Post-surgical adhesions are internal scar tissue and a major health and economic burden. Adhesions affect and involve the peritoneal lining of the abdominal cavity, which consists of a continuous mesothelial covering of the cavity wall and majority of internal organs. Our understanding of the full pathophysiology of adhesion formation is limited by the fact that the mechanisms regulating normal serosal repair and regeneration of the mesothelial layer are still being elucidated. Emerging evidence suggests that mesothelial cells do not simply form a passive barrier but perform a wide range of important regulatory functions including maintaining a healthy peritoneal homeostasis as well as orchestrating events leading to normal repair or pathological outcomes following injury. Here, we summarise recent advances in our understanding of serosal repair and adhesion formation with an emphasis on molecular mechanisms and novel gene expression signatures associated with these processes. We discuss changes in mesothelial biomolecular marker expression during peritoneal development, which may help, in part, to explain findings in adults from lineage tracing studies using experimental adhesion models. Lastly, we highlight examples of where local tissue specialisation may determine a particular response of peritoneal cells to injury.

Topics: Gene Expression Regulation, Developmental; Gene Regulatory Networks; Genetic Markers; Humans; Peritoneum; Tissue Adhesions

PubMed: 34063089
DOI: 10.3390/biom11050692

Authors: Kevin G Byrnes, Dara Walsh, Leon G Walsh...

The position of abdominal organs, and mechanisms by which these are centrally connected, are currently described in peritoneal terms. As part of the peritoneal model of abdominal anatomy, there are multiple mesenteries. Recent findings point to an alternative model in which digestive organs are connected to a single mesentery. Given that direct evidence of this is currently lacking, we investigated the development and shape of the entire mesentery. Here we confirm that, within the abdomen, there is one mesentery in which all abdominal digestive organs develop and remain connected to. We show that all abdominopelvic organs are organised into two, discrete anatomical domains, the mesenteric and non-mesenteric domain. A similar organisation occurs across a range of animal species. The findings clarify the anatomical foundation of the abdomen; at the foundation level, the abdomen comprises a visceral (i.e. mesenteric) and somatic (i.e. musculoskeletal) frame. The organisation at that level is a fundamental order that explains the positional anatomy of all abdominopelvic organs, vasculature and peritoneum. Collectively, the findings provide a novel start point from which to systemically characterise the abdomen and its contents.

Topics: Humans; Mesentery; Peritoneum

PubMed: 34408242
DOI: 10.1038/s42003-021-02496-1