Morphological changes of human peritoneum during peritoneal dialysis / 中华肾脏病杂志

ABSTRACT

Objective To investigate the morphological changes of peritoneum during peritoneal dialysis (PD) and elucidate the possible mechanism of its functional deterioration. Methods Peritoneal biopsies were obtained from normal subjects( n = 10), uremic predialysis patients( n = 12) at catheter insertion and PD patients ( n = 10) at the time of catheter remove or reinsertion or renal transplantation, peritoneal morphology was studied by light microscopy, scanning electron microscopy and transmission electron microscopy. Results Normal peritoneal membrane consisted of a monolayer of mesothelial cells on a basement membrane, and a layer of connective tissue containing cells, blood vessels, lymphatic vessels and so on. Mesothelial cells were polygonal, often elongated, and had numerous microvilli on their luminal surface. Sometimes the microvilli ended with roundish formation or resembled a corona. There were lots of oval or roundish pinocytotic vesicles in the cytoplasm of mesothelial cell. Submesothelial connective tissue contained many collagen and elastic fibers. The peritoneal morphology of uremic predialysis patients was similar to that of normal subjects. But significant abnormalities of peritoneal morphology were observed in PD patients and the changes were progressive. Microvilli were the first site of damage, including microvilli shortening, gradual reduction in number and following total disappearance. Then mesolhelial cell detachment from basement membrane and total disappearances were found. Finally the peritoneal membrane only consisted of submesothelial connective tissue denudation of cells. Conclusions PD can modify peritoneal morphology and structure. The morphological change is progressive and might be one of the important causes of peritoneal failure. Peritoneal biopsy can provide lots of valuable informations about the impact of PD, and thus further study on the relationship between peritoneal structure and its function is very useful for understanding of the physiopathology of peritoneum during PD.