Online ISSN: 1096-8652 Print ISSN: 0361-8609

American Journal of Hematology
Volume 73, Issue 4, 2003. Pages: 285-289

Published Online: 18 Jul 2003


Copyright © 2003 Wiley-Liss, Inc.


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Case Report
Thrombopoietin concentrations in peripheral blood correlated with platelet numbers in two patients with thrombocytopenia by chronic graft-versus-host disease

Yasuo Hirayama 1 *, Sumio Sakamaki 1, Yasushi Tsuji 1, Tamotsu Sagawa 2, Hiroki Chiba 2, Takuya Matsunaga 2, Hiroyuki Kuroda 2, Toshiro Kusakabe 2, Takehide Akiyama 2, Junji Kato 2, Yoshiro Niitsu 2
1Department of Internal Medicine, Higashi Sapporo Hospital, Sapporo, Japan
2Fourth Department of Internal Medicine Sapporo Medical University, Sapporo, Japan

email: Yasuo Hirayama (yhirayama@hsh.or.jp)


Abstract
Thrombocytopenia is well known to be one of the clinical manifestations of chronic graft-versus-host disease (cGVHD). However, there exist cases in which the cause of thrombocytopenia has been unexplained. Recently, thrombopoietin (TPO) from bone marrow (BM) stromal cells and transforming growth factor (TGF)- from platelets and megakaryocytes have been identified as strong positive and negative regulators of megakaryopoiesis in vivo. We hypothesized that the decreased TPO production from BM could be one of the causes of thrombocytopenia in the patients with cGVHD. In the present study, therefore, TPO and TGF- concentrations in peripheral blood (PB) and BM were measured serially in two patients with acute leukemia who had received fully matched stem cell transplantation from relatives and subsequently developed extensive cGVHD with thrombocytopenia. The results showed that platelet numbers correlated well with the TPO concentrations, which were consistently higher in BM than in PB. The difference in TPO concentrations between BM and PB was decreased when the platelet levels were low, indicating that the amount of TPO production from BM decreased throughout the duration of thrombocytopenia. TGF- concentrations were normal during all periods in which measurements were carried out. Thus, our results suggest that one mechanism of thrombocytopenia in patients with cGVHD is low TPO production by BM cells. Am. J. Hematol. 73:285-289, 2003. © 2003 Wiley-Liss, Inc.



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Received: 22 September 2002; Accepted: 15 April 2003