Limulus amebocyte lysate reactivity, complement activation, and patients' symptoms. Comparison of dialyzer membranes

This study was undertaken to clarify the role of Limulus amebocyte lysate reactive material (LAL-RM) in the activation of complement in patients during hemodialysis with cuprophan membranes. The authors measured LAL-RM and complement C3a levels predialysis and at 15 and 60 minutes of dialysis in 16 patients dialyzed for 8 weeks on cuprophan membranes and then for a succeeding 8 weeks on cellulose acetate membranes. Patients' symptoms on dialysis with each membrane were assessed. The LAL-RM levels of these patients were compared to those of six patients dialyzed on cellulose acetate membranes only. The LAL-RM and C3a levels rose significantly in the 16 patients while on dialysis with cuprophan membranes, but there was no correlation between the LAL-RM and C3a levels. C3a levels rose significantly in the 16 patients while on dialysis with cellulose acetate membranes, but there was no rise in LAL-RM levels. C3a levels were significantly lower while the patients were on dialysis with the cellulose acetate membranes. The six patients on dialysis with the cellulose acetate membranes only had no detectable LAL-RM in their blood. Patients' symptoms were less while on dialysis with the cellulose acetate membrane, but the difference did not achieve statistical significance. We conclude that LAL-RM plays a very minor role, if any, in the complement activation caused by cuprophan membranes and that cellulose acetate membranes do not release LAL-RM.