Journal List > Korean J Lab Med > v.30(3) > 1011638

Korean J Lab Med. 2010 Jun;30(3):244-248. Korean.
Published online June 30, 2010.
Copyright © 2010 The Korean Society for Laboratory Medicine
Acquired Amegakaryocytic Thrombocytopenia after Thymectomy in a Case of Pure Red Cell Aplasia Associated with Thymoma
Ah Ra Cho, M.D.,1 Young Joo Cha, M.D.,1 Hye Ryoun Kim, M.D.,1 Eun Kyung Park, M.D.,2 and Eun-Jong Cha, Ph.D.3
1Department of Laboratory Medicine, College of Medicine, Chung-Ang University, Seoul, Korea.
2Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea.
3Personalized Tumor Engineering Research Center (PTERC), College of Medicine, Chungbuk National University, Cheongju, Korea.

Corresponding author: Young Joo Cha, M.D. Department of Laboratory Medicine, Chung-Ang University College of Medicine, 224-1 Heukseok-dong, Dongjak-gu, Seoul 156-755, Korea. Tel: +82-2-6299-2720, Fax: +82-2-6298-8630, Email:
Received December 28, 2009; Revised March 22, 2010; Accepted April 30, 2010.


The association of thymoma with pure red cell aplasia has been well documented, but amegakaryocytic thrombocytopenia is not a recognized paraneoplastic syndrome complicating thymoma. We report a case of thymoma-complicated pure red cell aplasia and amegakaryocytic thrombocytopenia in a 73-yr-old woman. Pure red cell aplasia was diagnosed seven months after the detection of thymoma. One year after the diagnosis of pure red cell aplasia and seven months after thymectomy, bone marrow aspiration and biopsy showed an absence of megakaryocytes, marked erythroid hypoplasia with normal myeloid series. A diagnosis of amegakaryocytic thrombocytopenia and pure red cell aplasia was made. Oral steroid maintenance therapy resulted in recovery of platelet count. She has still transfusion-dependant anemia but platelet and neutrophil counts had been maintained in normal range for more than five months, until the last follow-up. We think that autoreactive T cells may induce a clinical autoimmune response even after eradication of thymoma, and aplastic anemia as a late complication following thymectomy was described in previous cases. This patient also has to be under a close observation because of the possibility to evolve into aplastic anemia.

Keywords: Thymoma; Pure red cell aplasia; Amegakaryocytic thrombocytopenia


Fig. 1
Bone marrow findings. (A) Hypocellular marrow with erythroid aplasia and adequate megakaryocytes at the diagnosis of pure red cell aplasia (hematoxylin and eosin stain, ×400). (B) Hypocellular marrow with erythroid aplasia and megakaryocytic aplasia at the seven months after thymectomy (hematoxylin and eosin stain, ×400).
Click for larger image

Fig. 2
Peripheral blood findings according to the clinical course.

Abbreviation: PRCA, pure red cell aplasia.

Click for larger image


This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0063258).

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