Peritoneal sclerosis and fibrosis include a broad spectrum of histopathological changes of the peritoneal membrane. The main macroscopic and microscopic findings include: thickening and sclerosis of the membrane with or without adhesions, dense and fibrous tissue, loss of mesothelial cells, deposition permeated with chronic inflammatory infiltrate, and in its most severe manifestation (encapsulated peritoneal sclerosis, EPS), encasement of the bowel by a new membrane resembling a cocoon(1).

The etiology of peritoneal sclerosis may be multifactorial. Among the postulated etiologies are uremic milieu, acetate containing peritoneal dialysis fluid (PDF), recurrent peritonitis, plasticizers, formaldehyde, pyrogens/endotoxin, multiple abdominal surgeries, chlorhexidine, hypertonic and acidic PDF and inflammatory or foreign body response to the peritoneal catheter.

Several pathologic mechanisms may contribute to the development of peritoneal sclerosis including: loss of normal cellular structure, loss of plasminogen activation from damaged mesothelial cells, impaired fibrinolysis, fibrosis, elevated levels of type I and III procollagen propeptide and the “plasma leak-to-response hypothesis”(2). The latter theory proposes that long term PD therapy leads to increased vascularity of the peritoneum and increased solute transport. Increased vascular surface area may result in plasma extravasation within the peritoneum and accumulation of fibrin-rich plasma exudates over the peritoneal surface. This is followed by migration of cellular components into the plasma and fibrin gel to form a de novo biomembrane.

Peritoneal sclerosis is an infrequent but potentially life-threatening complication of peritoneal dialysis therapy. The incidence is relatively low, estimated at 1.5 to 4.6 cases per 1,000 patient years, and the geographical distribution is variable, with the highest reported prevalence in Japan(3). A retrospective survey of eleven PD centers in Europe showed that the mortality rate of patients with EPS was approximately 50% within 12 months of diagnosis(4).

Diagnosis is based on clinical features such as bowel obstruction, ultrafiltration loss, reduced solute transport, anorexia, nausea, vomiting, weight loss, overhydration, ascites and hemoperitoneum(5). Non-specific laboratory markers (increased C-reactive protein and TGF_ß1 and decreased hemoglobin, serum albumin, CA-125 levels) and plain abdominal x-rays, contrast studies, CT scans or ultrasounds may also aid in establishing a diagnosis. Other methods include laparoscopy and biopsy (2).

Preventive measures recommended for encapsulating peritoneal sclerosis are:

• Avoidance of persistent hemoperitoneum
• Reduction of peritonitis rates
• Avoidance of hypertonic glucose solutions
• Use of biocompatible dialysis solutions
• Avoidance of beta blockers
• Peritoneal rest for at least one month in patients with type I ultrafiltration failure

Although definitive treatment options have not been characterized, the following have been suggested based on limited clinical experience:

• Avoidance of surgical intervention if conservative measures are successful
• Palliative surgery for obstruction and necrosis of the bowel
• Nutrition support
• Discontinuation of peritoneal dialysis
• Corticosteroid and immunosuppressant therapy have been successful in some case reports(4–8).

References

1. Brown EA, Van Biesen W, Finkelstein FO, Hurst H, Johnson DW, Kawanishi H, Pecoits-Filho R, Woodrow G. Length of time on peritoneal dialysis and encapsulating peritoneal sclerosis: position paper for ISPD. Perit Dial Int. 2009;29(6):595-600. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19910558.
2. Nakayama M. The plasma leak-to-response hypothesis: a working hypothesis on the pathogenesis of encapsulating peritoneal sclerosis after long-term peritoneal dialysis treatment. Perit Dial Int. 2005;25 Suppl 4:S71-S76. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16300275.
3. Yokota S, Kumano K, Sakai T. Prognosis for patients with sclerosing encapsulating peritonitis following CAPD. Adv Perit Dial. 1997;13:221-223. Available from: https://www.ncbi.nlm.nih.gov/pubmed/9360686.
4. Balasubramaniam G, Brown EA, Davenport A, Cairns H, Cooper B, Fan SLS, Farrington K, Gallagher H, Harnett P, Krausze S, et al. The Pan-Thames EPS study: treatment and outcomes of encapsulating peritoneal sclerosis. Nephrol Dial Transplant. 2009;24(10):3209-3215. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19211652.
5. Mori Y, Matsuo S, Sutoh H, Toriyama T, Kawahara H, Hotta N. A case of a dialysis patient with sclerosing peritonitis successfully treated with corticosteroid therapy alone. Am J Kidney Dis. 1997;30(2):275-278. Available from: https://www.ncbi.nlm.nih.gov/pubmed/9261041.
6. Diaz-Buxo JA. Peritoneal Sclerosis in a Woman on Continuous Cyclic Peritoneal Dialysis. Semin Dial. 2007;5(4):317-320. Available from: https://onlinelibrary.wiley.com/doi/10.1111/j.1525-139X.1992.tb00238.x/pdf.
7. Del Peso G, Bajo MA, Gil F, Aguilera A, Ros S, Costero O, Castro MJ, Selgas R. Clinical experience with tamoxifen in peritoneal fibrosing syndromes. Adv Perit Dial. 2003;19:32-35. Available from: https://www.ncbi.nlm.nih.gov/pubmed/14763031.
8. Eltoum MA, Wright S, Atchley J, Mason JC. Four consecutive cases of peritoneal dialysis-related encapsulating peritoneal sclerosis treated successfully with tamoxifen. Perit Dial Int. 2006;26(2):203-206. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16623426.

The information and reference materials contained in this document are intended solely for the general education of the reader. It is intended to provide pertinent data to assist you in forming your own conclusions and making decisions. This document should not be considered an endorsement of the information provided nor is it intended for treatment purposes and is not a substitute for professional evaluation and diagnosis. Additionally, this information is not intended to advocate any indication, dosage or other claim that is not covered, if applicable, in the FDA-approved label.

P/N 102495-01 Rev. A 06-2016