Dear Sir,
We appreciate the keen interest taken by Drs. Mahajan and Gaur for sending a correspondence in response to our article titled “Comorbidities in COVID-19: outcomes in hypertensive cohort and controversies with renin angiotensin system blockers” [1].
Although the authors are in agreement with the findings in general, however they have raised two questions in the correspondence. We agree that angiotensin-converting enzyme inhibitors do not increase angiotensin II, while angiotensin-receptor blockers have the potential to increase it. However, the hypothesis that the interaction of angiotensin converting enzyme-2 (ACE-2) with angiotensin II could lead to a conformational change in the receptor binding domain of ACE2 is not unfounded and has been put forth in the study on the X-Ray structure of ACE-2 [2]. With regards to other query about the purported protection of lung injury by the renin angiotensin system blockers (RASBs), we humbly inform that it has already been dealt with a great detail, which authors seems to have overlooked. Similarly, the figures in our article has much more detailed information on the interaction of renin angiotensin system blockers (RASBs), ACE-2 and coronavirus infectious disease 2019 (COVID-19).
We would like to reiterate again, that the benefit or harm with RASBs in COVID-19 is still a subject of debate and data at this point of time suggest a clinical equipoise. Some studies have shown a purported harm [3,4], while others have shown benefit [5]; the reason why we discussed both these issues in detail. However, we do not recommend to stop the RASB in patient with COVID-19.
References
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- 4.Million M., Lagier J.C., Gautret P. Bibliovid; 2020. Early treatment of 1061 COVID-19 patients with hydroxychloroquine and azithromycin, Marseille, France.https://www.mediterranee-infection.com/early-treatment-of-1061-covid-19-patients-with-hydroxychloroquine-and-azithromycin-marseille-france/ [DOI] [PMC free article] [PubMed] [Google Scholar]
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