Dynamics of blood count after rheohemapheresis in age-related macular degeneration: possible association with clinical changes.

Background: Rheohemapheresis (RHF) is a method that can stop the activity of the dry form of age-related macular degeneration (AMD). The pathophysiologic mechanisms are not well understood, and the effects of the RHF procedures extend beyond the time of the individual procedures.

Patients And Methods: We present the data for 46 patients with AMD treated with a series of 8 rheohemapheretic procedures. Blood count parameters were measured before the first and the last procedures. The clinical effect was judged by changes in the drusenoid pigment epithelium detachment (DPED) area before and after the rheopheretic sessions.

Results: Rheopheresis caused a decrease in hemoglobin (P<0.001), a decrease in leukocytes (P<0.034), and an increase in platelets (P<0.005). We found a negative correlation between the amount of platelets and their volume (P<0.001, Pearson correlation coefficient: -0.509). We identified the platelet/MPV ratio as a good predictor of the clinical outcome. Patients with a platelet/MPV ratio greater than 21.5 (before the last rheopheresis) had a significantly better outcome (P=0.003, sensitivity of 76.9% and specificity of 80%).

Conclusion: Several basic blood count parameters after RHF can be concluded to significantly change, with some of those changes correlating with the clinical results (reduction of the DPED area).