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Licensed Unlicensed Requires Authentication Published by De Gruyter February 23, 2022

The flagging features of the Sysmex XN-10 analyser for detecting platelet clumps and the impacts of platelet clumps on complete blood count parameters

Peng Xu, Kui Fang, Xiling Chen, Yangruiqi Liu, Zheqing Dong, Ji Zhu and Keda Lu



Platelet clumps present in anticoagulant specimens may generate a falsely decreased platelet count and lead to an incorrect diagnosis. A clear understanding of the ability of a haematology analyser (HA) to detect platelet clumps is important for routine work in the clinical laboratory.


Citrate-anticoagulated whole-blood samples were collected from various patients as a negative group. Adenosine diphosphate (ADP)-induced platelet aggregation was performed on those negative samples to mimic platelet-clump-containing (positive) samples. The ‘platelet clumps’ and ‘platelet abnormal’ flags generated by the Sysmex XN-10 instrument were used to assess the flagging performance of this HA and demonstrate its flagging features. The complete blood count (CBC) results of paired negative and positive samples were compared to evaluate the impact of platelet clumps on the CBC parameters.


A total of 187 samples were eligible for this study. The total accuracy, sensitivity, and specificity of the platelet clumps flag were 0.786, 0.626, and 0.947, respectively. The total accuracy, sensitivity, and specificity of the platelet abnormal flag were 0.631, 0.348, and 0.914, respectively. A separate assessment focusing on the positive samples with low platelet counts showed that the total sensitivities of the platelet clumps and platelet abnormal flags were 0.801 and 1.000, respectively. Platelet clumps may interfere with the leukocyte count and with platelet and erythrocyte indices.


Platelet clumps can influence not only platelet indices but also leukocyte and erythrocyte counts. The Sysmex XN-10 instrument is sensitive to positive samples with low platelet counts but insensitive to those with high platelet counts.

Corresponding author: Keda Lu, Zhejiang Chinese Medical University Affiliated Third Hospital, Hangzhou 310000, P.R. China, E-mail:
Peng Xu and Kui Fang contributed equally as co-first authors.

Funding source: Medical and Health Research Project of Zhejiang Province

Award Identifier / Grant number: 2022KY931

  1. Research funding: This work was supported by the Science Fund of the Medical and Health Research Project of Zhejiang Province. Project ID: 2022KY931.

  2. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Competing interests: The authors stated that there are no conflicts of interest regarding the publication of this article.

  4. Informed consent: Informed consent was obtained from all individuals included in this study.

  5. Ethical approval: The study was approved by the Institutional Research Ethics Committee of The Third Affiliated Hospital of Zhejiang Chinese Medical University.


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Received: 2021-11-24
Accepted: 2022-02-11
Published Online: 2022-02-23
Published in Print: 2022-04-26

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