Symptomatic subgemmal neurogenous plaque in patients with COVID-19: Is there an association?

BACKGROUND: Subgemmal neurogenous plaques (SNP) are composed of neural structures found in the posterolateral portion of the tongue, rarely biopsied as most of them are asymptomatic or eventually only clinically managed. We aimed to investigate a case series of possible correlation of symptomatic subgemmal neurogenous plaque (SNP) with coronavirus disease 2019 (COVID-19). METHODS: Eleven formalin-fixed paraffin-embedded cases from patients with previous confirmed COVID-19 (by RT-PCR) were retrieved from two pathology files. Histological sections were morphologically studied, and then submitted to immunohistochemical reactions against S-100 and neurofilament proteins, neuron-specific enolase, Glial fibrillary acidic protein (GFAP), synaptophysin, CD56, Ki67, cytokeratins (7, 8-18, 19, 20), nucleocapsid and spike proteins (SARS-CoV-1; and -2) and epithelial membrane antigen (EMA) antibodies. Clinical data were retrieved from the patients' medical files, including the symptoms and the complete history of the progression of the disease. RESULTS: The patients who had COVID-19 included in this study experienced painful lesions in the tongue that corresponded to prominent or altered SNP. Microscopically, neural structures were positive for S-100, GFAP and neurofilament protein. And the cellular proliferative index (by Ki-67) was very low. CONCLUSION: Thus, based on the current results, we hypothesize that symptomatic SNP may be a late manifestation of COVID-19 infection.

Oral Manifestations of Coronavirus Disease 2019 (COVID-19): A Comprehensive Clinicopathologic and Immunohistochemical Study.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents rapid transmission and significant mortality worldwide. It is responsible for coronavirus disease 2019 (COVID-19). The disease presents diverse clinical symptoms, including fever, cough, dyspnea, and pneumonia. However, other manifestations associated with COVID-19 need to be clarified, leading specialists to an early diagnosis and better prognosis. We describe the spectrum of clinicopathologic COVID-19-related oral lesions that can be the first and/or the unique manifestation of the disease. Fourteen patients with a mean age of 58 years (range: 23 to 88 y) with oral lesions were included. All patients were confirmed to be infected with SARS-CoV-2 by reverse transcription polymerase chain reaction testing. Patients demonstrated mild symptoms, including dysgeusia, anosmia, fever, and headache. The lesions were recognized and classified into 2 groups: (1) lesions caused by ischemia and/or hemorrhage and (2) lesions secondary to inflammatory events associated with viral load. The palate was most affected (n=8), followed by the tongue (n=4), and both the lip and palate (n=2). Histologic analysis demonstrated thrombosis of small arteries and capillaries, associated with areas of hemorrhage and chronic inflammatory infiltrate. Immunohistochemistry showed positive staining for spike protein (SARS-CoV and SARS-CoV-2) and angiotensin-converting enzyme 2 in the surface epithelium, salivary glands, inflammatory cells, and endothelial cells. Although the incidence of oral lesions among patients infected with SARS-CoV-2 appears to be uncommon, these findings suggest that the oral mucosa can also be a target organ for SARS-CoV-2.