Oral Manifestations of COVID-19

It was noted early in the pandemic that early signs of COVID-19 infection included dysosmia and dysgeusia.^43,44, It is also known that SARS-CoV-2, as well as SARS-CoV-1 and MERS, enter cells through binding to angiotensin-converting enzyme 2 receptor (ACE2), which is highly expressed in many cell types and, of particular interest to dental healthcare professionals, in oral mucosa and salivary glands. In particular ACE2 is expressed with higher density on the tongue dorsum and major and minor salivary glands in the buccal mucosa and palate.^43-48 Further, case reports published early in the pandemic described a myriad of oral manifestations of COVID-19 infection including: oral ulcerations, mucosal erosion, bullae, vesicle formation, pustules, fissured or depapillated tongue, macules, papules, increased and/or decreased pigmentation, halitosis, leukoplakia, hemorrhagic crust, oral tissue necrosis, petechiae, edema, erythema, and spontaneous bleeding.^45-49 It should also be noted that post-infection xerostomia has also been noted in a significant number of cases, even after resolution of other acute COVID-19 symptoms.⁴⁸

While reports in the current literature have a high level of heterogeneity, findings indicate that the prevalence of oral lesions was approximately 33% and aphthous lesions were found in approximately 10% of cases.⁴⁸ Multiple suggested diagnoses have been proposed for oral lesions associated with COVID-19 to include aphthous stomatitis, herpetiform lesions, candidiasis, vasculitis, Kawasaki-like, erythema multiforme-like, mucositis, necrotizing periodontal disease, angina bullosa-like, angular cheilitis, atypical Sweet syndrome, and Melkerson-Rosenthal syndrome.⁴⁵ Reported oral lesions were symptomatic in approximately 68% of cases and older individuals and those who presented with more severe systemic COVID-19 symptoms demonstrated more severe and widespread oral lesions.⁴⁵ Oral health measures, including poor oral hygiene and pre-existing oral disease, were also associated with higher rates and increased severity of COVID-19 associated oral lesions.^43,47,48, Current case reports do not allow for evaluation of all underlying etiologies for these oral lesions, including direct and/or indirect causation by the SARS-CoV-2 virus, secondary opportunistic infections, or coincidental outcomes.⁵⁰

Dental healthcare professionals should be aware that oral lesions may present as prodromal and/or early signs of COVID infection (Figure 3). In the case pictured below, an afebrile patient presenting with cough also noted oral lesions, dysgeusia and discomfort associated with the affected oral areas. Antigen COVID-19 tests on the day of presentation with oral lesions resulted in a negative test result, but PCR test performed the same day resulted in a positive test result that was available 24 hours after nasal swab testing. Identification of such lesions in combination with monitoring for other COVID-19 symptoms could result in earlier testing and/or referral to reduce asymptomatic/early SARS-CoV-2 spread. Additionally, a focus on establishing and promoting oral health as a mechanism to impact overall health is a critical learning point from the findings related to COVID-19 and oral health.

Figure 3: Oral Lesion Presenting Prior to frank COVID-19 Infection

Figure 3: Oral Lesion Presenting Prior to frank COVID-19 Infection

(Photo Courtesy of Dr. Mengyi (Lisa) Shi-Franks)