CUPROPHAN INDUCES GREATER CD62 EXPRESSION ON PLATELETS IN HEMODIALYSIS PATIENTS

During hemodialysis, the contact of blood and membranes result in platelet activation. Previous results on platelets activation during hemodialysis are not uniform. Platelet activation has recently been shown to play a key role in the development of advanced atherosclerotic lesions. Therefore we aimed to assess platelet activation induced by cuprammoniumtreated cellulose (cuprophan) and polysulfone dialyzers.in hemodialysis patients. Twenty-one end stage renal failure patients (9 M and 12 F; aged 43.5 ± 15.8 years, mean ± SD) who were on the chronic hemodialysis for at least three months were included in the study. The patients were sequentially dialyzed by cuprophan and polysulfone membrane, for a month with each membrane. Blood samples were obtained predialysis and postdialysis on the last dialysis session of one-month period with both membranes. As activation marker, CD62 expression of platelets was used. A flow cytometric analysis was performed in whole blood instead of platelet rich plasma used in previous studies to eliminate the activation caused by centrifiigation and washing. There was no significant change in the percentages of CD62-positive platelets by either membrane. However, postdialysis mean CD62 intensity of a platelet by cuprophan membrane significantly increased in comparison to predialysis value (p=0.01). Polysulfone membrane did not induce any significant change in mean CD62 intensity. Although postdialysis circulating activated platelets (the percentage of CD62-positive platelets x platelet count) by cuprophan were higher compared to predialysis count (p=0.037), there was not any significant difference by polysulfone. In conclusion: Cuprophan membrane induces platelet activation in chronic hemodialysis patients. There is a need for fitrther studies in terms of clinical implications of this study. However, we suggest that hemodialysis with dialyzers which cause platelet activation, may have an additional effect to morbidity for these patients.