Rise and exacerbation of oral lichen planus in the background of SARS-CoV-2 infection.

Oral Lichen Planus (OLP) is a chronic inflammatory disorder whose exact etiology remains unknown. Inflammatory mediators, cytotoxic CD8+ T cells and mast cells have been hypothesized to mediate the pathogenesis of OLP. COVID-19 pandemic caused by SARS-CoV-2 is marked by cytokine storms in the affected patients. Altered T-cell responses marked by exhaustion of T-cell count with hyperaggressive remaining T-cells and presence of cross-reactive antibodies render infected humans as fertile grounds for development of multisystem disorders. In addition, Vitamin D deficiency in COVID-19 patients can further modify the T cell mediated immunity. Increased circulating cytokines and hyperactive CD8+ T cells can alter the oral immune barriers rendering them susceptible to oral disorders. Due to the widespread immune dysregulation, it is possible that patients of COVID-19 may develop OLP in the aftermath or during recovery. The paper explores the pathogenic mechanism behind development OLP as post-COVID condition on account of their target receptor, T-cell responses, cytokine profile, mucosal immune barriers and nutrition deficiency.