Complement activation and coagulopathy - an ominous duo in COVID19
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Published on: August 4, 2023
Sojit Tomo1, Kiran Pvsn Kumar1, Dipayan Roy1
1Department of Biochemistry, AIIMS Jodhpur, Jodhpur, Rajasthan, India.
Insights
COVID-19 coagulopathy presents diagnostic challenges due to mixed complement-mediated and consumption features. Tailored anticoagulant therapy, considering D-dimer levels, is recommended over uniform approaches for better patient outcomes.
Area of Science:
- * Infectious Diseases
- * Hematology
- * Immunology
Background:
- * COVID-19 shares similarities with SARS and MERS, with severe cases exhibiting abnormal coagulation.
- * Immune-mediated pathology is significant in COVID-19, necessitating assessment of the complement system's role.
- * The complement system and coagulation cascade are intricately linked, influencing disease pathophysiology.
Purpose of the Study:
- * To discuss the pathophysiology of coagulopathy in COVID-19 patients.
- * To analyze the role of D-dimer in predicting COVID-19 severity.
- * To provide expert opinion on anticoagulant therapy for COVID-19.
Main Methods:
- * A comprehensive literature search was conducted on PubMed up to May 30, 2020.
- * Keywords included 'COVID-19', 'SARS-CoV-2', 'Coronavirus', 'Coagulopathy', and 'D-dimer'.
- * Twenty-two studies were included for a weighted pooled analysis of D-dimer.
Main Results:
- * Coagulopathy in COVID-19 shows mixed features of complement-mediated and consumption coagulopathy.
- * D-dimer levels are discussed in relation to predicting COVID-19 severity.
- * Atypical manifestations and varying D-dimer levels complicate uniform treatment recommendations.
Conclusions:
- * A tailored anticoagulant regimen, potentially intensifying standard prophylaxis with low-molecular-weight heparin, is advisable.
- * Uniform recommendations for anticoagulant therapy are insufficient due to atypical presentations and variable D-dimer levels.
- * Consideration of direct thrombin and platelet inhibitors on a patient-specific basis is recommended.
Introduction:
COVID-19 has similarities to the Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, as severe patients and non-survivors have frequently shown abnormal coagulation profiles. Immune-mediated pathology is a key player in this disease; hence, the role of the complement system needs assessment. The complement system and the coagulation cascade share an intricate network, where multiple mediators maintain a balance between both pathways. Coagulopathy in COVID-19, showing mixed features of complement-mediated and consumption coagulopathy, creates a dilemma in diagnosis and management.
Areas Covered:
Pathophysiology of coagulopathy in COVID-19 patients, with a particular focus on D-dimer and its role in predicting the severity of COVID-19 has been discussed. A comprehensive search of the medical literature on PubMed was done till May 30th, 2020 with the keywords 'COVID-19', 'SARS-CoV-2', 'Coronavirus', 'Coagulopathy', and 'D-dimer'. Twenty-two studies were taken for weighted pooled analysis of D-dimer.
Expert Opinion:
A tailored anticoagulant regimen, including intensification of standard prophylactic regimens with low-molecular-weight heparin is advisable for COVID-19 patients. Atypical manifestations and varying D-dimer levels seen in different populations bring forth the futility of uniform recommendations for anticoagulant therapy. Further, direct thrombin inhibitors and platelet inhibitors in a patient-specific manner should also be considered.
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