Assessing the Validity of an Abdominal CT Scoring System in the Diagnosis of Encapsulating Peritoneal Sclerosis

Abstract

Background and objectives: Encapsulating peritoneal sclerosis (EPS) is a severe peritoneal fibrotic reaction in patients on long-term peritoneal dialysis (PD). The early clinical features may be nonspecific. The purpose of the study is to assess the reliability and diagnostic utility of abdominal CT scanning in the diagnosis of EPS.Design, setting, participants, & measurements: Abdominopelvic CT scans of 27 patients diagnosed with EPS on clinical and radiologic grounds in our unit from 1997 to 2006 were retrospectively analyzed. In addition, 35 control CT scans were scored: 15 from hemodialysis patients (HD controls) and 20 from patients on PD (PD controls). Scans were anonymized and scored independently by three radiologists.Results: Inter-rater agreement was moderate to very good (kappa ‫؍‬ 0.40 to 0.75) for peritoneal calcification, bowel distribution, bowel wall thickening, and bowel dilation but poorer for loculation of ascites and peritoneal thickening. There was a strongly significant difference between the total CT scan scores at EPS diagnosis and controls (P < 0.00001). Each individual parameter also showed significant differences between EPS and controls (P < 0.006). Bowel tethering and peritoneal calcification were the most specific parameters, and. loculation was the least discriminatory parameter. Interestingly, prediagnostic scans a median of 1.5 yr before EPS diagnosis were normal or near-normal in 9 of 13 EPS patients.Conclusions: CT scanning is a valid and reliable adjunct to the diagnosis of EPS but may not be useful as a screening tool, as the prediagnostic scans did not show abnormalities in many patients who subsequently developed EPS.

Sclerosing encapsulating peritonitis

“…The characteristic pre-visceral membrane which encases the tethered and matted bowel loops is demonstrated only in the late stages of the disease. 17 On CT scans, peritoneal thickening, peritoneal calcification, loculated fluid collections, and tethering of the small bowel appear to be diagnostic of SEP. More importantly, in a Case Report 18 Nevertheless, Tarzi and colleagues 19 suggested that CT scanning may not be useful as a screening tool for SEP as the scan is frequently normal even a few months before the fulminant illness. 19 Another possible explanation for their findings is that CT scanning may not be sensitive enough to detect early SEP.…”

Towards Standardized Reporting in Studies of Encapsulating Peritoneal Sclerosis

“…The resulting scores differentiated the groups well and produced good interobserver agreement; however, CT scores did not necessarily reflect disease activity (13).…”

Encapsulating Peritoneal Sclerosis in Incident PD Patients in Scotland

“…At present radiological techniques are unable to establish a diagnosis of "early" EPS. CT scans which were performed coincidentally in PD patients prior to development of EPS did not show features indicating developing EPS (Tarzi et al 2008). Thus there is no evidence that regular screening of long-term PD patients by radiological techniques would be able to detect pre-symptomatic EPS or beneficially alter PD management.…”