Abstract Number: PB0279
Meeting: ISTH 2021 Congress
Theme: COVID and Coagulation » COVID and Coagulation, Clinical
Background: Activation of the coagulation system, as reflected by raised D-dimers, is prevalent in patients with COVID-19 resulting in coagulopathies as well as venous and arterial macro- and micro-thromboses. Laboratory tests in patients admitted with COVID-19 should include prothrombin time (PT) and D-dimers. The role of platelets in COVID-19 related immunothrombosis has not been extensively documented.
Aims: Investigate platelet indices in patients with COVID-19 with raised D-dimer levels and compare the results to COVID-19 infected patients with normal D-dimer levels as well as to COVID-19 uninfected patients with raised D-dimers.
Methods: This retrospective observational study was approved by the Human Research Ethics Committee of the University of the Witwatersrand (M201010). The laboratory results of patients admitted to a quaternary referral centre in Johannesburg, South Africa from June to December 2020 were reviewed. Platelet indices including platelet large cell ratio (P-LCR), mean platelet volume (MPV) and platelet distribution width (PDW) were recorded and analysed in the following 3 cohorts: 281 COVID‐19 patients with raised D-dimers, 72 COVID-19 patients without raised D-dimers and 51 COVID-19 negative patients with raised D-dimers and disseminated intravascular coagulation (DIC).
Results: The platelet indices P-LCR, MPV and PDW in COVID-19 positive patients were statistically different from patients without COVID-19 (P < 0.001) (Table 1). No statistically significant difference in the platelet indices was however observed between COVID-19 patients with and without raised D-dimers.
| Parameter | COVID-19 positive (n=353) | COVID-19 negative (n=51) | P-value | |||
| Mean | SD | Mean | SD | |||
| Platelet count (x109/L) | 264.16 | ±124.15 | 291.45 | ±91.23 | 0.14 | |
| P-LCR(%) | 31.06 | ±7.82 | 25.26 | ±6.09 | <0.001 | |
| MPV(fl) | 10.8 | ±1 | 10.08 | ±0.73 | <0.001 | |
| PDW(fl) | 12.74 | ±2.52 | 11.31 | ±1.63 | <0.001 | |
Platelet parameters in COVID-19 positive patients with and without raised D-dimers vs. COVID-19 negative patients with raised D-dimers
COVID-19, Corona virus disease-19; n, number of patients; SD, standard deviation; P-LCR, platelet large cell ratio; MPV, mean platelet volume; PDW, platelet distribution width.
Conclusions: Platelet laboratory indices are statistically different between COVID‐19 positive and COVID-19 negative patients but were not predictive of the presence of an underlying coagulopathy in COVID-19 as reflected by elevated D-dimer levels. The alterations in platelet indices in COVID-19 patients probably reflect activation of platelets and contribution to immunothrombosis.
To cite this abstract in AMA style:
Mezgebe M, Jacobson BF, Louw S. Change in Platelet Indices in Patients with Coronavirus Infection Disease (COVID-19): A Reflection of Platelet Activation and Contribution to Immunothrombosis? [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/change-in-platelet-indices-in-patients-with-coronavirus-infection-disease-covid-19-a-reflection-of-platelet-activation-and-contribution-to-immunothrombosis/. Accessed December 10, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/change-in-platelet-indices-in-patients-with-coronavirus-infection-disease-covid-19-a-reflection-of-platelet-activation-and-contribution-to-immunothrombosis/