ORIGINAL ARTICLESPatients with severe coronavirus disease 2019 have high frequency of factor 5 Leiden and prothrombin gene mutationsAvci, Burcu Altindağ; Doğan, Mustafa; Batar, Bahadir; Yildirim, İlker; Serdal, Elif; Gezer, Sümbül; Onar, Çağatay L.; Akpinar, Seval; Turgut, Burhan Author Information Burcu Altindağ Avci, MD, Department of Hematology, Tekirdağ Namik Kemal University, Tekirdağ, Turkey Correspondence to Burcu Altindağ Avci, MD, Department of Hematology, Tekirdağ Namik Kemal University, Tekirdağ, Turkey E-mail: [email protected] Received 29 April, 2022 Revised 10 July, 2022 Accepted 19 August, 2022 Blood Coagulation & Fibrinolysis 34(1):p 14-19, January 2023. | DOI: 10.1097/MBC.0000000000001167 Buy Metrics Abstract We investigated the frequency of factor 5 Leiden (FVL) and prothrombin gene (PTG) mutations in patients with severe coronavirus disease 2019 (COVID-19). Our primary aim is to reveal whether these mutations are associated with severity of disease and mortality. A total of 249 patients were included in this cross-sectional study. Severe COVID-19 cases (with oxygen saturation of less than 90 mmHg and who received ventilation support invasively or noninvasively) were included. FVL and PTG mutations were identified by real time- PCR technique. Frequency of mutations for FVL was 11.7%, whereas for PTG was 3.5%. The frequency of FVL and PTG's mutations in our patient group was found to be significantly higher than the normal population (P < 0.0001, 0.004, respectively). There was no difference in the frequency of mutations of FVL and PTG between the patients ventilated – invasively and noninvasively. There was also no difference in D-dimer, ferritin, fibrinogen, ex status, and entubational status between the groups of FVL and PTG mutated and wild-type. To the best of our knowledge, it is the first time that we have examined the frequencies of FVL and PGM's mutations in severe COVID-19 disease on such a large scale. The frequencies of both mutations in severe COVID-19 patients were higher than in the healthy population. We believe that studies prospectively designed, including asymptomatic and mild COVID-19 patients, will provide more comprehensive information on the subject. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.