Oxidative metabolism of polymorphonuclear leukocytes in continuous ambulatory peritoneal dialysis

To evaluate the oxidative metabolism of polymorphonuclear leukocytes (PMNL) in continuous ambulatory peritoneal dialysis (CAPD) patients compared with those of hemodialysis (HD) patients, chronic renal failure (CRF) patients not yet on dialysis, and healthy controls; and to discover factors contributing to the oxidative function in CAPD patients.

Thirty-five CAPD, 22 HD, 11 CRF patients were assessed; all were free from infections at the time of examination. Thirty-one healthy volunteers served as controls.

The oxidative metabolism was estimated by the production of superoxide anion, which was detected by luminol-dependent zymosan stimulated chemiluminescence (CL) with whole blood assessment. The volume of superoxide production equivalent to 1 mL of circulating blood (T-CL), that equivalent to 10(4) neutrophils (CL/N) and the velocity of superoxide production (V-CL), were measured as parameters for the oxidative function of PMNL.

There were no differences in all CL parameters between CAPD and HD patients. T-CL and CL/N of dialysis patients were equal to controls but those of CRF patients were significantly decreased. V-CL of dialysis patients, as well as CRF patients, was smaller than that of controls but the difference was not significant. Among nutritional status, degree of anemia, dialytic efficacy and duration of dialysis in CAPD patients, only serum albumin concentration (Alb) correlated well to all CL parameters. Hypoalbuminemic patients (Alb < 3.6 g/dL, n = 20) had significantly decreased T-CL and CL/N compared to normoalbuminemic patients (Alb > or = 3.6 g/dL, n = 15), and decreased CL/N and V-CL compared to controls. No differences in CL parameters were observed between the patients with a history of peritonitis (n = 15) and without a history of peritonitis (n = 20).

Oxidative metabolism of PMNL in CAPD patients was maintained with respect to superoxide productive volume, while the oxidative velocity was relatively impaired. Furthermore, it seems that albumin has a great influence on the oxidative metabolism of PMNL in CAPD patients.