Generation of leukotriene B4 by hemodialyzer membranes: A novel index of biocompatibility

Summary Leukotriene B₄ (LTB₄) plays an important role in acute and chronic inflammatory and hypersensitive reactions. We studied the time course of LTB₄ biosynthesis in whole blood in 18 patients with end-stage renal failure maintained on regular hemodialysis with two different membranes, cuprophane and polyacrylonitrile (AN 69). The basal levels of LTB₄ from dialysis patients did not differ significantly from a normal control group. Compared to predialytic values, the cuprophane membrane caused a maximal release of LTB₄ by a factor of about 4.5 (p<0.01) within the first 10 to 20 minutes. Thereafter the level fell and returned to baseline range at the end of the hemodialysis session. With the use of the AN 69 membrane no significant increase of LTB₄ could be demonstrated. The changes in LTB₄ concentration showed a close temporal correlation to the alterations in white blood cell count. We conclude that (1) LTB4 is a biologically important mediator of neutrophil activation during hemodialysis, and (2) LTB₄ may be a sensitive marker of biocompatibility in vivo.Abbreviations LTB₄ Leukotriene B₄ - 5-HETE 5-Hydroxyeicosatetraenoic acid