Journal of Rheumatic Diseases  2015;22(1):51-55

doi:10.4078/jrd.2015.22.1.51

A Case of Essential Thrombocythemia in a Patient with Ankylosing Spondylitis Concomitantly Treated with Adalimumab.

Dae Sung LEE 1 ; Seung Geun LEE ; Ho Jin SHIN ; Sun Hee LEE ; Eun Kyoung PARK ; Hae Jung NA ; Chul Hong PARK ; Ji Heh PARK ; In Sub HAN ; Geun Tae KIM

Affiliations

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Keywords

Ankylosing spondylitis; Essential thrombocythemia; Tumor necrosis factor alpha

Country

Republic of Korea

Language

English

Abstract

Extreme thrombocytosis in patients with ankylosing spondylitis (AS) is rarely reported. Because the relationship between high disease activity and increased platelet counts is somewhat contradictory, severe thrombocytosis in AS patients can be secondary to infection, iron deficiency anemia, drug administration, and hematologic malignancies. Essential thrombocythemia (ET) is a rare acquired stem cell neoplasm characterized by overproduction of platelets by megakaryocytes in the bone marrow in the absence of other causes of thrombocytosis. There is no report in the literature regarding the association between AS and ET. We report on a case of a 34-year-old Korean man with active AS diagnosed as JAK2V617F mutation negative ET during adalimumab treatment.