Exploring the link between burning mouth syndrome and human herpesvirus-6B: a narrative review on pathogenesis

Abstract

Burning Mouth Syndrome (BMS) presents as a persistent, often perplexing pain condition characterised primarily by a sensation of burning, yet frequently lacks observable clinical evidence. The underlying mechanisms of BMS remain elusive. Typically, the tongue bears the brunt of the discomfort, followed by the inner lower lip and hard palate. Psychologically, BMS often intersects with anxiety and depression, forming common comorbidities. There's emerging research suggesting a potential link between Human Herpesvirus 6B (HHV-6B) and mental health disorders. This association raises the possibility of HHV-6B as a contributor to BMS. HHV-6B's hypothesised involvement in BMS could be from various avenues: direct damage to taste cells and nerves, eliciting an inflammatory response, or even disrupting olfactory functions. This narrative review aims to critically evaluate the current literature on the potential association between HHV-6B and BMS. It explores the role of HHV-6B in pain mechanisms, inflammatory responses, and its impact on sensory functions such as taste and olfaction, providing a comprehensive overview of its implications in BMS pathogenesis.

Keywords: Burning mouth syndrome; dysaesthesia; human herpesvirus 6B; taste; taste bud.

Figure 1.

Direct viral contact and replication in host cells leading to taste cell destruction. Herpesviridae, including HHV-6B, can infiltrate and replicate within various cell types, including taste cells, oral epithelium, lymphocytes, and dendritic cells through distinct stages: the initial phase, invasion phase, and late phase. During the initial phase, the virus gains entry into host cells. In the invasion phase, viral replication intensifies, leading to direct viral contact and potential destruction of taste cells. In the late phase, as injured taste cells release viral particles, neighbouring taste cells, epithelial cells, and neurons may also suffer damage, potentially eliciting a burning sensation – a hallmark symptom of conditions like Burning Mouth Syndrome. (Created with BioRender.com).

Figure 2.

HHV-6B presence in cranial nerve, including the olfactory, facial, and trigeminal nerves. These nerves play a critical role in sensory processing, including taste and smell perception. During severe primary infection or reactivation of the virus, damage or dysfunction in these nerve regions can occur. This damage may disrupt the normal transmission of sensory signals, leading to altered or diminished taste and smell, symptoms often observed in viral-related sensory neuropathies. Additionally, viral reactivation in these nerves could exacerbate conditions like Burning Mouth Syndrome, which is characterised by sensory abnormalities, including a burning sensation in the mouth. (Created with BioRender.com).