T细胞大颗粒淋巴细胞（LGL）白血病的特征是CD3+T细胞的克隆增殖，并且与类风湿性关节炎（RA）有关联。脾脏肿大是常见的发现，大多数病例表现为细胞减少症。弗尔蒂综合征（FS）的特征是中性粒细胞减少和脾脏肿大，其与RA的关联已在文献中得到经典描述。FS和T细胞LGL白血病在临床特征、发病机制、治疗、遗传学和免疫学基础方面的相似性导致了它们存在于同一疾病谱的建议。我们报告了一个RA患者中T细胞LGL白血病的病例，其临床特征与FS的特征无法区分。2023年版权所有，Prasad et al.

T-cell large granular lymphocytic (LGL) leukemia is characterized by a clonal proliferation of CD3+ T-cells and has been associated with rheumatoid arthritis (RA). Splenomegaly is a common finding and a majority of cases present with cytopenia. Felty syndrome (FS) is characterized by neutropenia and splenomegaly and is also classically described in the literature for its association with RA. Similarities in clinical features, pathogenesis, management, genetics, and immunologic basis of FS and T-cell LGL leukemia have led to the suggestion that they exist on the same spectrum of disease. We present a case of T-cell LGL leukemia in an RA patient with clinical features not distinguishable from features of FS.Copyright © 2023, Prasad et al.