Re: Response to the emerging novel coronavirus outbreak
Loss of smell and taste in the course of COVID-19 infection may be related to angiotensin converting enzyme (ACE) inhibition
Very recently, there has been reports of loss of smell and taste in the course of COVID-19 infection. The report from the presidents of the British Association of Otorhinolaryngology and British Rhinological Society noted that there has been growing number of reports of a significant increase in COVID-19 patients presenting with loss of smell in the absence of other symptoms . Moreover, they suggested anosmia can be added to the current symptom criteria to trigger quarantine and/or self-isolation to limit dissemination of the COVID-19 .
In the former report , we suggested that there seems to be some ongoing ACE inhibition during COVID-19 infectious process because AngII is shown as increased in patients with COVID-19 and increased AngII causes decreased ACE mRNA levels in the lung and decrease in pulmonary ACE activity . The dry cough, which is a very common presentation of COVID-19 infection, may be related to this ACE inhibition . Of note, loss of smell and taste is a well-known effect of ACE inhibitors . While post-viral anosmia is a common causes of loss of smell sensation, loss of smell/taste may be more common in COVID-19 infections regarding this pathophysiological process. We suggest that the ACE inhibition that is present in COVID-19 infections may be the cause of the loss of smell/taste symptomatology, which seems to be specifically common in COVID-19 infections.
3. Schunkert H, Ingelfinger JR, Hirsch AT, Pinto Y, Remme WJ, Jacob H, Dzau VJ. Feedback regulation of angiotensin converting enzyme activity and mRNA levels by angiotensin II. Circ Res. 1993;72:312-8.
4. Bromley SM. Smell and taste disorders: a primary care approach. Am Fam
Physician. 2000;61:427-36, 438.
Competing interests: No competing interests