Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Department and Graduate Institute of Pathology, National Taiwan University, Taipei, Taiwan.
Neuropathol Appl Neurobiol. 2024 Apr;50(2):e12960. doi: 10.1111/nan.12960.
Olfactory dysfunction is one of the most common symptoms of COVID-19. In the first 2 years of the pandemic, it was frequently reported, although its incidence has significantly decreased with the emergence of the Omicron variant, which has since become the dominant viral strain. Nevertheless, many patients continue to suffer from persistent dysosmia and dysgeusia, making COVID-19-associated olfactory dysfunction an ongoing health concern. The proposed pathogenic mechanisms of COVID-19-associated olfactory dysfunction are complex and likely multifactorial. While evidence suggests that infection of sustentacular cells and associated mucosal inflammation may be the culprit of acute, transient smell loss, alterations in other components of the olfactory system (e.g., olfactory receptor neuron dysfunction, olfactory bulb injury and alterations in the olfactory cortex) may lead to persistent, long-term olfactory dysfunction. This review aims to provide a comprehensive summary of the epidemiology, clinical manifestations and current understanding of the pathogenic mechanisms of COVID-19-associated olfactory dysfunction.
嗅觉功能障碍是 COVID-19 的最常见症状之一。在疫情的头 2 年，它经常被报道，尽管随着奥密克戎变异株的出现，其发病率显著下降，此后该变异株已成为主要的病毒株。然而，许多患者仍持续遭受持续性嗅觉障碍和味觉障碍，使 COVID-19 相关的嗅觉功能障碍成为一个持续存在的健康问题。COVID-19 相关嗅觉功能障碍的潜在发病机制复杂，可能涉及多种因素。虽然有证据表明，支持细胞和相关黏膜炎症的感染可能是急性、短暂性嗅觉丧失的罪魁祸首，但嗅觉系统其他成分的改变（例如，嗅觉受体神经元功能障碍、嗅球损伤和嗅皮层改变）可能导致持续性、长期的嗅觉功能障碍。本综述旨在全面总结 COVID-19 相关嗅觉功能障碍的流行病学、临床表现和发病机制的现有认识。
