Does infection of 2019 novel coronavirus cause acute and/or chronic sialadenitis?

Abstract

2019 novel coronavirus (2019-nCoV) is widespread in China and other countries. The target of 2019-nCoV and severe acute respiratory syndrome coronavirus (SARS-CoV) is angiotensin-converting enzyme 2 (ACE2) positive cells. ACE2 is present in the salivary gland duct epithelium, and thus it could be the target of 2019-nCoV and SARS-CoV. SARS-CoV-related animal model experiments show that it can infect the epithelial cells on the salivary gland duct in Chinese rhesus macaques by targeting ACE2. Clinical studies confirmed that 2019-nCoV and SARS-CoV could be detected in saliva of human patients. We hypothesize that the infection of 2019-nCoV and SARS-CoV will lead to inflammatory pathological lesions in patients' target organs, and possibly inflammatory lesions in salivary glands. 2019-nCoV may cause acute sialoadenitis in the acute phase of infection. After the acute phase, chronic sialoadenitis may be caused by fibrosis repairment. Although there was no direct evidence to prove this, the available indirect evidence indicates a high probability of our hypothesis.

COVID-19 in the act: incidental 18F-FDG PET/CT findings in asymptomatic patients and those with symptoms not primarily correlated with COVID-19 during the United Kingdom coronavirus lockdown

“…We observed a significant increase of parotid/salivary gland FDG uptake in patients scanned during the 2nd week compared to patients scanned during the 1st week. This is in accordance with a published hypothesis that SARS-CoV-2 may cause acute sialadenitis due to increased ACE-2 receptor expression in the salivary glands, supported by the observation that the virus can be detected in saliva [23]. This may also be followed by symptoms of discomfort, pain or swelling of the salivary glands; however, these symptoms may be overlooked during established COVID-19 assessment thus far, which is mostly based on fever and respiratory symptoms.…”

Insufficient etiological workup of COVID-19-associated acute pancreatitis: A systematic review

“…As de-Madaria et al [ 11 ] pointed out in reflecting on Wang et al [ 9 ], the elevation of pancreatic enzyme levels in the blood is not necessarily a consequence of an insult to the pancreas. Possible reasons are the high prevalence of renal impairment and diabetes mellitus, gastroenteritis, and metabolic changes, such as acidosis, or even salivary glandular entry by SARS CoV-2[ 39 - 42 ]. More importantly, a slight elevation in serum amylase and/or lipase levels alone is not established as an indicator of pancreatic damage.…”

Presencia y Expresión del Receptor ACE2 (Target de SARS-CoV-2) en Tejidos Humanos y Cavidad Oral. Posibles Rutas de Infección en Órganos Orales

“…No obstante, existen estudios que sí reportan la presencia de ACE2 en la cavidad oral, aunque, estos son muy limitados. En estos, se evidencia presencia de ACE2 en células de glándulas salívales y en células de la mucosa oral (Xu et al, 2020a,b;Wang et al, 2020).…”

“…Se ha demostrado que células epiteliales de glándulas salivales y de la mucosa oral expresan el receptor ACE2 y teóricamente podrían ser sitios de infección por SARS-CoV-2 (Chen et al, 2020b;Wang et al;Xu et al, 2020b). Sin embargo, limitados estudios explican cómo se daría este proceso infectivo y que síntomas podrían manifestarse asociados a la enfermedad COVID-19 en la cavidad oral (Peng et al).…”