Is heparin therapy necessary in CAPD peritonitis?

Abstract

Objective: Heparin therapy in continuous ambulatory peritoneal dialysis (CAPD) peritonitis seems well established; it is costly due to the necessity of hospitalization. There are no clinical studies that show a benefit of such a treatment. The aim of this study was to investigate whether heparin therapy in CAPD peritonitis isnecessary. Design and Patients: 194 samples of peritoneal dialysates were collected from 17 patients over a period of 24 months. Samples were subdivided into three groups: those without peritonitis (< 100 leukocytes/μL), those with mild peritonitis (100-499 leukocytes/μL), and those with severe peritonitis (≤ 500 leukocytes/μL). Measurements: The number of leukocytes per μL dialysate and total protein concentrations were determined. Furthermore, dialysate concentrations of thrombin-antithrombin III- (TAT-) complexes (indicator of thrombin formation), D-dimers (indicator of fibrinolysis), and plasminogen activator inhibitor 1 (PAI-1) were measured. Results: The dialysate protein concentration progressively increased from no peritonitis to mild and severe inflammation. In parallel, dialysate TAT-complex and D-dimer concentrations increased. Thrombin-antithrombin Ill-complex and D-dimer concentrations correlated strongly in 179 cases (r = 0.76; 62 samples showing peritonitis, 117 samples with no evidence of peritonitis). In the remaining 15 samples of 3 patients, high PAI-1 levels(> 40 ng/mL) and low D-dimer concentrations were found. Eleven of the 15 samples showed evidence of peritonitis. In these 11 samples with evidence of peritonitis, high levels of TAT-complexes were detected, while D-dimer concentrations were found to be very low, pointing to a blocked fibrinolysis. The PAI-1 levels were not related to leukocyte counts or protein concentrations in the dialysates. Conclusions: Based on our findings, the routine intraperitoneal administration of heparin in CAPD peritonitis is not necessary. In rare cases an imbalance between coagulation and fibrinolysis due to high PAI-1 levels exists (15 of 194 dialysate samples, 11 of the 15 samples showing peritonitis). These cases - which do require heparinization - can be identified by demonstrating low D-dimer levels in CAPD dialysate at times of peritonitis.