Abstract：
Growing evidence exists about post-COVID condition/syndrome as sequelae of Sars-CoV-2 infection in healed patients, possibly involving the lungs, brain, kidney, cardiovascular and neuromuscular system, as well the persistency of taste dysfunction. Such symptoms develop during or after infection and continue for more than 12 weeks with pathogenesis related to virus persistency but variable by organs or systems.
We recently observed six patients recovered from COVID-19 and with negative RT-PCR testing, showing oral mucosa lesions (mainly ulcers) overlapping those occurring in the acute phase, persisting up to 20 days and thus needing a biopsy with histological investigation and spike protein evaluation by immunohistochemistry.
We found epithelial ulceration, inflammatory infiltrate, vessels with increased diameter and flattened endothelium but no thrombi formation; also, we found a weak epithelial SARS-CoV-2 positivity limited to the basal/spinosum layers, progressively decreasing toward the periphery, and the intraepithelial lymphomonocytes, endothelium, and perivascular pericytes too.
Our findings provide evidence that SARS-CoV-2 can persist, as for other organs/systems, also in the oral epithelium/mucosa after the acute phase and can be responsible for lesions, although by a pathogenetic mechanism that should be better defined but certainly referable as the oral mucosa counterpart of post-COVID syndrome.
We recently observed six patients recovered from COVID-19 and with negative RT-PCR testing, showing oral mucosa lesions (mainly ulcers) overlapping those occurring in the acute phase, persisting up to 20 days and thus needing a biopsy with histological investigation and spike protein evaluation by immunohistochemistry.
We found epithelial ulceration, inflammatory infiltrate, vessels with increased diameter and flattened endothelium but no thrombi formation; also, we found a weak epithelial SARS-CoV-2 positivity limited to the basal/spinosum layers, progressively decreasing toward the periphery, and the intraepithelial lymphomonocytes, endothelium, and perivascular pericytes too.
Our findings provide evidence that SARS-CoV-2 can persist, as for other organs/systems, also in the oral epithelium/mucosa after the acute phase and can be responsible for lesions, although by a pathogenetic mechanism that should be better defined but certainly referable as the oral mucosa counterpart of post-COVID syndrome.
摘要：
目的：有越来越多的证据表明，在已治愈的患者中，COVID后的病情/综合征是Sars-CoV-2感染的后遗症，可能涉及肺部，大脑,肾,心血管和神经肌肉系统，以及味觉功能障碍的持续性。此类症状在感染期间或之后发展,并且持续超过12周,发病机理与病毒持久性相关,但因器官或系统而异。
方法：我们最近观察到6名患者从COVID-19中康复，RT-PCR检测阴性，显示口腔粘膜病变（主要是溃疡）重叠发生在急性期，持续长达20天，因此需要进行活检，进行组织学检查，并通过免疫组织化学进行刺突蛋白评估。
结果：我们发现上皮性溃疡，炎症浸润,血管直径增大，内皮变平，但无血栓形成；我们发现一个弱的上皮SARS-CoV-2阳性局限于基底/棘层，向外围逐渐减少，和上皮内淋巴单核细胞，内皮,还有血管周细胞.
结论：我们的发现提供了SARS-CoV-2可以持续存在的证据，至于其他器官/系统，也在急性期后的口腔上皮/粘膜中，可以引起病变，尽管通过应该更好地定义的致病机制，但肯定可称为COVID后综合征的口腔粘膜对应物。
方法：我们最近观察到6名患者从COVID-19中康复，RT-PCR检测阴性，
结果：我们发现上皮性溃疡，
结论：我们的发现提供了SARS-CoV-2可以持续存在的证据，
