Patients who experienced mild or no upper respiratory symptoms developed tongue ulcers within a few days of testing positive for SARS-CoV-2 in a new analysis, described in a letter to the editor on September 5 in Oral Diseases.
Tongue ulcers may be an early symptom of infection by the virus, and the early susceptibility of the oral mucosa to SARS-CoV-2 may be due to high expression of angiotensin‐converting enzyme 2 (ACE2) in epithelial cells of the tongue, the authors wrote.
"Tongue ulcers can be a direct manifestation of SARS-CoV-2 infection or as co-infection due to the immune dysregulation," wrote the authors, led by Abanoub Riad, DDS, PhD, a research fellow in the Czech National Centre for Evidence-Based Healthcare and Knowledge Translation at Masaryk University.
Some evidence has shown a link between oral manifestations, including mouth rashes, and the novel coronavirus, triggering debates about cause, prognosis, and significance. The researchers believe they have been underreported or discovered accidentally due some patients' inability to seek regular exams and the low fatality of oral mucocutaneous lesions such as herpes simplex virus and chronic canker sores. To better understand this, Case Reports (CARE) guidelines were used to demonstrate the characteristics of 26 laboratory-confirmed COVID-19 patients with tongue ulcers.
About the patients
The researchers used hospital records to analyze the demographic, clinical, and laboratory traits of patients who had tongue ulcers and visited the hospital between April and June 2020. Initially, these patients were suspected of having SARS-CoV-2 due to confirmed cases among members of their households. Polymerase chain reaction (PCR) tests confirmed their infections. None of the patients had underlying conditions, most had mild or no respiratory symptoms, and none were hospitalized. As for symptoms typically associated with SARS-CoV-2, four patients had a fever, three lost their sense of taste, one had a dry cough, and two had a sore throat, according to the authors.
Ulcers come early
Approximately 54% of patients developed tongue ulcers five days after they were tested for SARS-CoV-2. The rest developed them within four days or had them on the day of testing. None of the patients reported a history of mouth sores or ulcers, according to Dr. Riad and colleagues.
Intraoral exams revealed that all patients had ulcers on the dorsum or side of the tongue, and a few also had them on the ventral surface. The number of ulcers ranged from one to seven per patient. Only a few had ulcers that bled, they wrote.
The patients were prescribed oral paracetamol and told to use chlorhexidine mouthwash. The ulcers disappeared within one to two weeks.
The authors analyzed the records of the SARS-CoV-2-positive patients to enhance existing evidence about the connection between oral manifestations and COVID-19, they noted.
"To the best of our knowledge, this case series is the largest to date to give an epidemiologic account on the tongue ulcers adjacent to SARS-CoV-2 infection with mild or no upper respiratory symptoms," the group wrote.