Thrombopoietic cytokines and reversal of thrombocytopenia after liver transplantation

Objectives Thrombopoietin (TPO), the key regulator of platelet production, is mainly produced by the liver and reduced expression of TPO could cause t hrombocytopenia in liver cirrhosis. Reversal of thrombocytopenia by orthoto pic liver transplantation seems to be mediated through an increase in TPO p lasma levels after transplantation, but other cytokines with thrombopoietic activity could augment the actions of TPO on post transplant platelet reco very. Design Measurement of thrombopoietic cytokines before and for 14 days post liver transplantation in a cohort of thrombocytopenic liver transplant pati ents. Methods TPO, interleukin-3 (IL-3), IL-6, and IL-11 plasma levels as well as peripheral platelet count were analysed in thrombocytopenic patients with liver disease undergoing orthotopic liver transplantation (17 patients) and followed for 14 days after the intervention. Results Before liver transplantation, TPO plasma levels were undetectable a nd IL-3, IL-6, and IL-11 levels were normal, Sixteen out of 17 patients sho wed a significant rise of TPO levels within 2 days after transplantation, w ith a peak between days 4 and 6, while IL-3 and IL-6 levels did not show a significant rise. IL-11 levels remained normal, Platelet counts were signif icantly higher than pre-transplantation levels by day 14 post transplantati on. Conclusion Restitution of normal TPO production by liver replacement seems to be of key importance for reversal of thrombocytopenia in liver disease. The early acting thrombopoietic factor IL-3 and the late acting factors IL- 6 and IL-11 do not play a major role for recovery of peripheral platelet co unt after orthotopic liver transplantation. (C)1999 Lippincott Williams & W ilkins.