Acute thrombocytopenia after liver transplant: Role of platelet activation, thrombopoietin deficiency and response to high dose intravenous IgG treatment q Angelo Nascimbene 1, * , Matteo Iannacone 2 , Bruno Brando 3 , Andrea De Gasperi 4 1 Department of Internal Medicine, University of Texas at Houston, 6431 Fannin Street, Suite 1.134, Houston, TX 77030, USA 2 Immunopathogenesis of Liver Infections Unit, San Raffaele Scientific Institute, Via Olgettina 58, Milan 20132, Italy 3 Transfusional Medicine Department, Azienda Ospedaliera Legnano, Legnano, Italy 4 Liver Transplant Unit, Ospedale Niguarda Ca’Granda, Milan, Italy See Editorial, pages x–y Background/ Aims: Thrombocytopenia is common after liver transplantation due to platelet sequestration secondary to hypersplenism. The aim of this study was to further investigate the causes of this condition, as well as the response of thrombocytopenia to high dose intravenous immunoglobulins. Methods: We retrospectively studied 73 patients who underwent liver transplantation. Out of these 73 patients, 27 had severe thrombocytopenia and were treated with high dose intravenous immunoglobulin. Additionally, we retrospectively studied 8 patients undergoing liver transplantation. Results: Our data suggest that splenomegaly is not the only factor responsible for thrombocytopenia after liver trans- plantion and two additional phenomena, namely, reduced platelet production due to reduced thrombopoietin level and sus- tained platelets activation take part in the pathogenesis of this condition. The infusion of high dose immunoglobulins induced a safe, prompt, complete and persistent resolution of severe thrombocytopenia in more than 70% of patients. Conclusions: Based on these findings, treatment with high dose intravenous immunoglobulins should be considered in the management of severe thrombocytopenia after liver transplant, although additional randomized trials are warranted. Ó 2007 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. Keywords: Platelet; Liver transplant; Thrombocytopenia 1. Introduction Thrombocytopenia is a common complication among liver transplant recipients [1]. Early after ortho- topic liver transplantation (OLT), thrombocytopenia affects 90% of patients and it results in an average 60% reduction in platelet count [1–4]. Thrombocytope- nia peaks 4–5 days following surgery and the platelet count returns to preoperative levels 2–3 weeks after transplant [5]. Nearly 8% of OLT patients suffer from severe thrombocytopenia with platelet count lower than 20 · 10 3 /lL. Moderate and severe thrombocyto- penia in the post-OLT setting limits diagnostic assess- 0168-8278/$32.00 Ó 2007 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.jhep.2007.06.012 Received 2 January 2007; received in revised form 23 May 2007; accepted 13 June 2007 Associate Editor: P.A. Clavien q The authors who have taken part in this study declared that they have no relationship with the manufacturers of the drugs involved either in the past or present and did not receive funding from the manufacturers to carry out their research. They did not receive funding from any source to carry out this study. * Corresponding author. Tel.: +1 713 500 6525; fax: +1 713 500 6530. E-mail address: Angelo.Nascimbene@uth.tmc.edu (A. Nascimbene). www.elsevier.com/locate/jhep Journal of Hepatology xxx (2007) xxx–xxx DOCTOPIC: Transplantation Please cite this article in press as: Nascimbene A et al., Acute thrombocytopenia after liver transplant: Role of platelet ..., J He- patol (2007), doi:10.1016/j.jhep.2007.06.012 ARTICLE IN PRESS