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Review
. 2021 Jul 14;21(6):38.
doi: 10.1007/s11882-021-01015-w.

Clinical-Pathological Correlation of the Pathophysiology and Mechanism of Action of COVID-19 - a Primer for Clinicians

Jeremy Chee  1 , Woei Shyang Loh  1   2 , Zheng Liu  3 , Joaquim Mullol  4 , De Yun Wang  5   6
Affiliations
Review

Clinical-Pathological Correlation of the Pathophysiology and Mechanism of Action of COVID-19 - a Primer for Clinicians

Jeremy Chee et al. Curr Allergy Asthma Rep. .

Abstract

Purpose of review: Increasing knowledge of the pathogenesis of the SARS-CoV-2 infection and the complex interaction between host and viral factors have allowed clinicians to stratify the severity of COVID-19 infection. Epidemiological data has also helped to model viral carriage and infectivity. This review presents a comprehensive summary of the pathophysiology of COVID-19, the mechanisms of action of the SARS-CoV-2 virus, and the correlation with the clinical and biochemical characteristics of the disease.

Recent findings: ACE2 and TMPRSS2 receptors have emerged as a key player in the mechanism of infection of SARS-CoV-2. Their distribution throughout the body has been shown to impact the organ-specific manifestations of COVID-19. The immune-evasive and subsequently immunoregulative properties of SARS-CoV-2 are also shown to be implicated in disease proliferation and progression. Information gleaned from the virological properties of SARS-CoV-2 is consistent with and reflects the clinical behavior of the COVID-19 infection. Further study of specific clinical phenotypes and severity classes of COVID-19 may assist in the development of targeted therapeutics to halt progression of disease from mild to moderate-severe. As the understanding of the pathophysiology and mechanism of action of SARS-CoV-2 continues to grow, it is our hope that better and more effective treatment options continue to emerge.

Keywords: COVID-19; Epidemiology; Mechanism of action; Pandemic; Pathogenesis; Pathophysiology.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
SARS-CoV-2 and nasal viral entry. This figure simulates a sagittal view of the lateral wall of the nose. After inhalation, viral particles are captured within the mucus secretions. Cellular uptake is then mediated by the ACE2 and TMPRSS2 receptors. These receptors are found in the sustentacular cells of the olfactory epithelium and goblet and ciliated cells of the nasal respiratory epithelium
Fig. 2
Fig. 2
Progress of severity of illness in relation to course of disease. WHO-China Joint Commission classes of severity of disease in COVID-19 infection as shown in proportion to the host immune response. This is mediated by a combination of viral load, viral clearance, and dysregulated hyperproliferation of the host immune system
See this image and copyright information in PMC

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