July27Unitedkingdom  2021 


Abstract Volume: 3 Issue: 1 ISSN:

Post-Acute-COVID-19-Illness Hematological Sequelae
Ruangrong Cheepsattayakorn1, Attapon Cheepsattayakorn 2,3*,Porntep  Siriwanarangsun3


1.Department  of  Pathology, Faculty  of  Medicine, Chiang  Mai  University, Chiang  Mai, Thailand.

2.10th  Zonal  Tuberculosis  and  Chest  Disease  Center, Chiang  Mai, Thailand.

3.Faculty  of  Medicine, Western  University, Pathumtani  Province, Thailand.

Corresponding Author: Attapon Cheepsattayakorn, 10th Zonal Tuberculosis  and  Chest  Disease  Center, 143  Sridornchai  Road  Changklan  Muang  Chiang  Mai  50100  Thailand.

Copy Right: © 2021 Attapon Cheepsattayakorn. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received Date: June 17, 2021

Published date: July 01, 2021

Post-Acute-COVID-19-Illness Hematological Sequelae

A 2.5 % cumulative incidence of thrombosis, including ischemic stroke, intracardiac thrombus, segmental pulmonary embolism, and thrombosed arteriovenous fistula at 30 days (median duration of 23 days post-discharge) and a 3.7 % cumulative incidence of bleeding, mostly associated with mechanical falls at 30 days after hospital discharge were reported in 163 post-acute-COVID-19-illness patients from the US without post-hospital-discharge thromboprophylaxis [1]. Several previous retrospective studies in the UK revealed similar rates of venous thromboembolism (VTE) [2, 3]. A previous prospective study in Belgium in 102 post-acute-COVID-19-illness patients at 6 weeks post-hospital-discharge follow-up by assessing D-dimer levels and venous ultrasonography revealed that only one asymptomatic VTE event occurred among 8 % of subjects who received post-hospital-discharge [4]. Hypercoagulable state and hyper inflammation were consistent in COVID-19-related coagulopathy [5, 6], contributing to the disproportionately high rates of 20 %-30 % of thromboembolic events rather than bleeding events in the acute COVID-19 phase [7]. The severity and duration of a hyperinflammatory state with unknown persistence are probably associated with the risk of thromboembolic events in the post-acute-COVID-19-illness phase [8]. Release of pro-inflammatory cytokines [9], disruption of normal coagulation pathway [10], complement activation [11-13], neutrophil extracellular traps [12, 14, 15], endothelial injury [16, 17-19], platelet-leukocyte interactions and platelet activation [20-22], and hypoxia [23] are the proposed mechanisms of the thrombo-inflammation. These mechanisms are similar to the pathophysiology that are present in thrombotic microangiopathy syndromes [24]. CORE-19, CISCO-19, and CORONA-VTE are the larger ongoing studies that will assist in establishing thromboembolic complications in the post-acute-COVID-19-illness phase [ 25, 26]. Due to lacking the need to frequently monitor the therapeutic levels and the lower risk of drug-drug interactions, low-molecular-weight heparin and direct oral anticoagulants are preferred anticoagulation drugs over vitamin K antagonists [27, 28]. Similar to provoked VTE, for patients with imaging-confirmed VTE, at least 3 months of therapeutic anticoagulation is recommended [29, 30]. In addition to comorbidities, such as immobility and cancer, the elevation of D-dimer levels (higher than two times the upper limit of the normal value) may be a benefit to risk-stratify cases at the highest risk of post-acute-COVID-19-illness thrombosis [25, 27, 28, 31]. Aspirin, an alternative antiplatelet agent for COVID-19 or post-acute-COVID-19-illness thromboprophylaxis has not yet been defined and is presently studied in cases managed as outpatients [9]. In hospital-discharge-COVID-19 patients with outpatient management, extended post-hospital discharge, up to 6 weeks and prolonged primary thromboprophylaxis, up to 45 days may provide a more favorable risk-benefit ratio in COVID-19 with an increase in thrombotic events during the acute COVID-19 phase, and this is currently being studied [32, 33].

In conclusion, in addition to post-acute-COVID-19-illness primary thromboprophylaxis, when appropriate, ambulation and physical activity should be recommended to all patients.



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