Oral lichen planus induced by long-term use of antimicrobials for recurrent aphthous ulcer: A case report and literature review.

The precise etiology of oral lichen planus (OLP) is still unclear, but the existing evidence suggests that drug intake, virus infection, fungal infection, psychological disorders, and immunodeficiency are closely associated with the pathogenesis of OLP. We report a case of OLP accompanied with candidiasis induced by long-term use of antimicrobials for recurrent aphthous ulcer (RAU) and update the literature, to discuss the possible association between OLP and misuse of antimicrobials, and to inform general dentists and pharmacists the importance for practice with optimal antimicrobial stewardship. In this case, a 42-year-old man presented to Xiangya Stomatological Hospital with white reticular patterns spreading in the oral cavity for almost 1 year. He was diagnosed with OLP via histopathological examination. He had a 5-year history of RAU which occurred every 1-2 months, and he was given antimicrobials ingested or injected whenever the ulcers came up. Satisfactory treatment results were obtained by stopping the abuse of antimicrobials and local antifungal therapy. Meanwhile, the exacerbation and alleviation of OLP was closely related to the administration of antimicrobials. Combined with literature review, antimicrobial might contribute to the development of OLP by inducing candidiasis, a common side-effect of misuse of antimicrobials. Considering the seriousness of antimicrobial resistance and opportunistic infection, dentists should prescribe antimicrobials judiciously according to guidelines and evidence-based indications. Appropriate prescribing of antimicrobials is a professional responsibility to all dentists.