The major clinical manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection are due to pulmonary complications. The majority of the patients so far in the COVID-19 pandemic had milder symptoms including fever, headache, cough, dyspnoea, myalgia and anosmia. Approximately 10-20% of all the cases are severe and life-threatening, and the patients may need intensive care unit (ICU) admission with ventilation support. In a cohort of patients with SARS-CoV2 infection hospitalized in Wuhan, China (January 2020) 26% were admitted to the ICU because of complications, which included acute respiratory distress syndrome (61%), arrhythmia (44%), and shock (31%). The median time from the first symptom to dyspnoea was 5 days and to ICU admission was 8 days (1).
The authors of this review (2) article hypothesize that respiratory dysfunction could be explained in part by the well-known neuroinvasive potential of coronaviruses. Indeed, there is experimental data which demonstrated that coronaviruses are able to spread via a synapse‐connected route from the mechano- and chemoreceptors which are located in the lung and the lower respiratory tract to the medullary cardiorespiratory center. Of note, angiotensin converting enzyme 2 (ACE2) receptor, which enables the cellular entry of SARS-CoV2, is also abundant in neurons and glial cells. Thus, the authors argue that central cardiorespiratory failure may be the cause of life-threatening complications in some patients infected with SARS-CoV2.
While the neurotropism of SARS-CoV2 needs to be confirmed, neurologists need to be aware of this potential cause of neurologic COVID-19 complication. Moreover, clinical studies should evaluate whether this hypothesis can be substantiated.
References:
1. Wang D, Hu B, Hu C, et al. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. JAMA. 2020 Feb 7. doi: 10.1001/jama.2020.1585. [Epub ahead of print]
2. Li Y, Bai W, Hashikawa T. The Neuroinvasive potential of SARS-CoV2 may play a role in the respiratory failure of COVID-19 patients. Journal of Medical Virology 2020, in press. https://doi.org/10.1002/jmv.25728