Leukotriene B4 is involved in hemodialysis-associated neutropenia

Biosynthesis of leukotriene B4 (LTB4) was studied in ten patients with end-stage renal failure undergoing chronic hemodialysis with a cuprophane membrane. As compared to healthy subjects the low basal plasma levels of LTB4 quantified by radioimmunoassay after extraction and purification by HPLC showed no significant difference. The time-course of LTB4 release after contact of the blood with the dialysis membrane without further in vitro stimulation was characterized by a rapid increase by about 500% within the first 10 min, appearing approximately at the same time as the known fall of white blood cell count which reaches its nadir after 20 min. Analysis of further release showed a decline of LTB4 biosynthesis to basal levels at the end of hemodialysis. These results indicate that activation of the 5-lipoxygenase pathway is involved in hemodialysis-associated leukopenia and may contribute to the alterations in neutrophils of patients with chronic dialysis therapy.