Structural and ultrastructural peritoneal membrane changes and permeability alterations during continuous ambulatory peritoneal dialysis.

Normal and abnormal structure of the peritoneum is described in biopsies obtained from 15 cadavers and 13 patients on continuous ambulatory peritoneal dialysis (CAPD) at the onset of their treatment and after several months. In a few patients a loss of ultrafiltration due to a higher permeability of the peritoneum for glucose was observed. This hyperpermeability seems to be due to a patchy or total destruction of the mesothelium; it seems also to be dependent upon the thickness of the fibrous band separating capillaries from the peritoneal cavity. The endothelium of capillaries was normal in all the specimens examined.