Analysis of laboratory and instrumental markers of endothelial dysfunction in children with SARS-CoV-2 associated pneumonia and its relationship with the JAK2 V617F gene polymorphism

SARS-CoV-2 may act as a trigger for the initiation of immunopathological processes such as endothelial dysfunction. Aim - to determine the levels of endothelial dysfunction in children with SARS-CoV-2-associated pneumonia and to analyze its relationship with the JAK2 V617F gene polymorphism. Materials and methods. The main study group included 160 children with SARS-CoV-2-associated pneumonia, while the control group comprised 40 healthy children. The main group was stratified by sex, age, severity of disease, levels of pro-inflammatory proteins, structural indices of the vascular wall, and functional measures of endothelial status. The presence of the JAK2 V617F gene polymorphism was assessed using polymerase chain reaction. Results. The JAK2 V617F gene polymorphism was detected in 138 children (86.25±2.47%) with SARS-CoV-2-associated pneumonia and was significantly more frequent in those with severe disease. Among 132 children (82.5%) with pulmonary and extrapulmonary complications, 94 (95.9%) had a severe course of SARS-CoV-2-associated pneumonia. In children with complicated pneumonia, the JAK2 V617F gene polymorphism was diagnosed significantly more often. Children with SARS-CoV-2-associated pneumonia carrying the JAK2 V617F polymorphism demonstrated higher levels of C-reactive protein (by 42.95%), procalcitonin (by 19.01%), fibrinogen (by 14.89%), and D-dimer (by 34.53%), as well as elevated levels of interleukins 1 and 6, endothelin-1, and vascular endothelial growth factor (by 25.12%, 29.22%, 35.04%, and 36.12%, respectively). The mean value of flow-mediated dilation was significantly higher in children with severe SARS-CoV-2-associated pneumonia. Children with a non-severe course of pneumonia without the JAK2 V617F polymorphism had a 41.67% lower carotid intima-media thickness. Conclusions. Children with SARS-CoV-2-associated pneumonia had a more severe course of disease, which correlated with the presence of the JAK2 V617F gene polymorphism. Severe pneumonia with pulmonary and extrapulmonary complications was more frequently observed in patients with the identified JAK2 V617F polymorphism. The study was conducted in accordance with the principles of the Declaration of Helsinki. The study protocol was approved by the local institutional ethics committee. Informed consent was obtained from all participants. The authors declare no conflict of interest.