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Bone Marrow Transplantation Procedures in Mice to Study Clonal Hematopoiesis
Published on: May 26, 2021
Clonal hematopoiesis is associated with risk of severe Covid-19
Insights
Clonal hematopoiesis (CH) is linked to severe COVID-19 and increased risk of bacterial infections like C. difficile and Streptococcus. This suggests CH may heighten susceptibility to serious infections.
Area of Science:
- Hematology
- Immunology
- Infectious Diseases
Background:
- Clonal hematopoiesis (CH) involves somatic mutations in blood stem cells, linked to aging and disease risk.
- CH is associated with inflammation, which can worsen outcomes in infections like COVID-19.
- The relationship between CH and infection severity, including COVID-19, remains unclear.
Conclusions:
- Clonal hematopoiesis is associated with severe COVID-19.
- CH may increase the risk of specific bacterial infections, warranting further research.
Abstract:
Acquired somatic mutations in hematopoietic stem and progenitor cells (clonal hematopoiesis or CH) are associated with advanced age, increased risk of cardiovascular and malignant diseases, and decreased overall survival. 1-4 These adverse sequelae may be mediated by altered inflammatory profiles observed in patients with CH. 2,5,6 A pro-inflammatory immunologic profile is also associated with worse outcomes of certain infections, including SARS-CoV-2 and its associated disease Covid-19. 7,8 Whether CH predisposes to severe Covid-19 or other infections is unknown. Among 515 individuals with Covid-19 from Memorial Sloan Kettering (MSK) and the Korean Clonal Hematopoiesis (KoCH) consortia, we found that CH was associated with severe Covid-19 outcomes (OR=1.9, 95%=1.2-2.9, p=0.01). We further explored the relationship between CH and risk of other infections in 14,211 solid tumor patients at MSK. CH was significantly associated with risk of Clostridium Difficile (HR=2.0, 95% CI: 1.2-3.3, p=6×10 -3 ) and Streptococcus/Enterococcus infections (HR=1.5, 95% CI=1.1-2.1, p=5×10 -3 ). These findings suggest a relationship between CH and risk of severe infections that warrants further investigation.
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