Correlation between serum Angiotensin II level and severity of COVID-19 disease

Abstract Background Coronavirus disease 2019 (COVID-19) is a global pandemic caused by novel coronavirus SARS-CoV-2. Angiotensin-converting enzyme 2 (ACE2) is a key player in the pathophysiology of COVID-19, as it facilitates the cellular viral entry, which in turn causes upregulation of Angiotensin II (Ang II) which correlates with the severity of infection and inflammation. Objectives Assessing the serum levels of Ang-II among COVID-19 patients, and correlate it with disease severity. Patients and methods Eighty patients of COVID- 19 and 80 healthy subjects were enrolled in this cross sectional study. COVID-19 patients was divided to 4 groups; mild, moderate, severe, and critical groups, according to WHO classification of severity of the disease .Beside clinical, laboratory (CBC, CRP, D-dimer, liver and kidney function tests) and imaging assessment, Ang II level was measured using ELISA kits. Results Levels of Ang-II are significantly higher in COVID-19 patients (281.82 ± 114.54 pg/dl) compared to control (72.53 ± 21.86 pg/dl), with a p-value < 0.001. Significant higher levels were detected in severe and critical cases, which were 347.65 ± 37.70 and 436.06 ± 53.00, respectively, as compared to mild and moderate cases, which were 132.16 ± 27.98 and 216.44 ± 49.47 pg/dl, respectively. An ROC curve for detection of the cutoff value of Ang II level was 115.5 pg/dl with an AUC of 0.990. Moreover, a cutoff value of Ang II for determining the severe and critical cases was 300.05 pg/dl with an AUC of 1.000. Conclusion Ang-II may be a potential biomarker that could aid in determining the severity of cases aiming at the development of therapeutic strategies to mitigate disease severity.