Absence of gadolinium deposits in the peritoneal membrane of patients with encapsulating peritoneal sclerosis

Background. Encapsulating peritoneal sclerosis (EPS) is a severe complication of long-term peritoneal dialysis (PD) characterized by the development of an extensive fibrosis of the visceral peritoneum that may eventually lead to intestinal constriction. Its cause remains elusive. Nephrogenic systemic fibrosis (NSF), a disabling disease that can follow gadolinium-based contrast injection during magnetic resonance imaging, is characterized by systemic fibrosis of the skin, joints, liver, heart and vessels. Affected tissues are infiltrated by CD34+ and CD68+ fibroblasts. In the present study, we tested the hypothesis that EPS could have been triggered by a previous gadolinium injection. Methods. We performed histopathological analysis of the peritoneal membrane of two EPS and two control patients all exposed to long-term PD, including immunostaining with CD34 and CD68. The presence of gadolinium and other metals was also assessed by conventional and energy-filtered transmission electron microscopy.