Abstract
We report the pathological findings of the peritoneum in a patient with chronic eosinophilic peritonitis. Peripheral blood eosinophilia was confirmed before insertion of Tenckhoff catheter. Eosinophilic peritonitis continued from the second day after initiation of peritoneal dialysis for 18 months. Pathological findings showed numerous eosinophils in peritoneal blood vessels. Mast cells were also detected in the peritoneum, while neoangiogenesis was not prominent. The highly permeable state of the peritoneal membrane may be due to inflammatory mediators, such as tryptase. Mast cells may be involved in high peritoneal permeability in such patients.