Supplementary Material for: Interesting Mucocutaneous Manifestations in COVID-19 Infection or Vaccination Confirmed by Histopathology: A Case Series

Mucocutaneous complications or adverse events due to SARS-CoV-2 infection or vaccination have been well-delineated in the literature, respectively. Most eruptions are considered to be mild and self-limiting; however, for the atypical cases which have a tentative clinical diagnosis, performing a biopsy and histopathological assessment is pivotal to confirm the diagnosis and subsequently prescribe a more tailored treatment. Despite the diverse reporting of such incidents globally, the rate of biopsied cases is restricted to less than 15% in most studies.

This case series elucidates 20 patients referred to the tertiary dermatology clinic, including 14 COVID-19 infection-related eruptions such as Lichen Planus (LP), Cutaneous vasculitis, Pityriasis rosea (PR), Discoid lupus erythematosus, Guttate psoriasis, Sarcoidosis, Raynaud's phenomenon, non-specific lesions resembling genital warts, Beau's line and one severe case of purpura fulminans with a promising outcome. Moreover, we presented 6 vaccine-induced cases comprising LP, Urticarial vasculitis, PR, Parapsoriasis, and Localized Morphea. The diagnosis of all cases has been proven by histopathological evaluation. We included pertaining anamnesis details of each patient together with vivid classifying images to pinpoint the morphologic features of each condition.

In line with our previous studies, the vaccine-induced eruptions were less severe compared to infection-related complications of COVID-19 and are mostly controllable by antihistamines and corticosteroids administration. Therefore, reporting such events should not hinder COVID-19 vaccination in the general population.

由严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染或疫苗接种引发的皮肤黏膜并发症与不良事件，此前已分别在文献中得到充分阐述。多数皮肤损害表现为轻症且具有自限性；但对于临床初步诊断尚不明确的非典型病例，实施活检及组织病理学评估对于明确诊断并制定个体化治疗方案至关重要。尽管全球范围内此类病例的报道形式多样，但多数研究中活检病例占比均不足15%。

本病例系列研究纳入了转诊至三级皮肤科门诊的20例患者，其中14例为新型冠状病毒肺炎（COVID-19）感染相关皮损，包括扁平苔藓（Lichen Planus, LP）、皮肤血管炎、玫瑰糠疹（Pityriasis rosea, PR）、盘状红斑狼疮、滴状银屑病、结节病、雷诺现象、类似生殖器疣的非特异性皮损、博氏线，以及1例暴发性紫癜重症病例，该病例预后良好。此外，本研究还纳入了6例疫苗诱导性皮损病例，涵盖LP、荨麻疹性血管炎、PR、副银屑病及局限性硬斑病。所有病例的诊断均经组织病理学检查证实。本研究纳入了每位患者的详细病史资料，并配有清晰的分类图像，以明确各病症的形态学特征。

与我们此前的研究结果一致，新冠疫苗诱导性皮损的严重程度低于新冠病毒感染相关并发症，且多数可通过抗组胺药与糖皮质激素治疗得到控制。因此，此类事件的报道不应阻碍普通人群接种新冠疫苗。