LEUKOPENIA AND RHEOLOGICAL ANOMALIES IN LEUKOCYTES DURING HEMODIALYSIS IN PATIENTS WITH CHRONIC-RENAL-FAILURE

In order to clarify the relation between leukopenia during hemodialysi s and leukocyte adhesiveness, the number of circulating leukocytes, th eir filterability through 5-mu m diameter pores, and the concentration of neutrophil elastase in plasma were measured in peripheral blood co llected at the beginning of hemodialysis (dialyzer, cuprophane membran e), 15 min into dialysis, and end of dialysis (duration of dialysis, 1 80 min) in 15 patients with chronic renal failure. Leukopenia was most marked at 15 min in all patients. In accordance with the change in nu mber of circulating leukocytes, the filtration time of the leukocytes, as determined by a modification of the Nuclepore filtration method (f iltered blood volume 0.5 mi, leukocyte count 2,500/mu l, suction press ure 10 cm H2O, temperature 37 degrees C) was significantly longer at 1 5 min versus the beginning and end of the dialysis (p < 0.005 and p < 0.025, respectively). Addition of the chemotactic peptide, N-formyl-me thionyl-leucyl-phenylalanine (FMLP; 20 nM), to the suspensions immedia tely increased the leukocyte filtration time. Such FMLP-induced increa ses were significantly greater at 15 min versus the beginning of dialy sis (p < 0.05). This heightened sensitivity of cells to FMLP appeared to persist until the end of dialysis (p < 0.05 versus the beginning). Plasma levels of neutrophil elastases were highest at the end of dialy sis versus those at the beginning and after 15 min (both p < 0.005). R esults suggest that the changes in filterability of leukocytes may be related to decreases in their number in the circulation. Neutrophil el astase appeared to accumulate in plasma so that its maximal value at t he end of dialysis would reflect the preceding changes in leukocyte rh eology.