LAUSR

Dear Editors, Platelet satellitism (PS) is classically described as an in vitro phenomenon of platelet rosetting around the cytoplasm of neutro‐ phils. This condition is observed in ethylenediaminetetraacetic acid (EDTA) anticoagulated blood sample at room temperature.1 The clinical relevance of PS resides in that it is an important cause of spurious thrombocytopenia and it can lead to unnecessary evalu‐ ations and treatment. The appearance of PS is unusual and occurs mainly around neutrophils. PS around other cells like lymphocytes has rarely been mentioned in the literature, and its presence could indicate a malignant process. Therefore, we would like to report our recent finding of PS in abnormal lymphocyte. A 64‐year‐old man followed up in our institution for a medical history of diabetes mellitus presented with lymphocytosis in rou‐ tine analytical control. Automated hematology analyzer (DxH‐800, Beckman Coulter) showed a “variant lymphocyte” flag (Figure 1. Image 7). Complete blood cell analysis revealed a leukocyte count of 19.90 ×109/L, lymphocytosis of 12.8 ×109/L, hemoglobin con‐ centration of 13.6 g/dL, and platelet count of 284 ×109/L. May‐ Grünwald‐stained peripheral blood smear examination revealed a 27% of moderate‐sized abnormal lymphocytes with regular nuclei, mature chromatin, visible nucleoli, and little villi projections in cyto‐ plasm. In addition, we observed platelet satellitism around abnormal lymphocytes in the blood smear review but not around neutrophils or normal lymphocytes (Figure 1. Images 1‐6). The platelet satellit‐ ism around lymphocytes was present in subsequent samples, and the platelet count was stable. The flow cytometric analysis showed an increase in CD19‐positive cells which had a heterogeneous side scatter. Surface immunoglobulin expression was kappa‐restricted and of moderate‐high intensity. CD5, CD10, CD43, and CD103 were not coexpressed with CD19 and CD20 was intensely positive, lead‐ ing to a working diagnosis of a B‐cell lymphoproliferative disorder