Abstract：
BACKGROUND: Despite the advancements in the categorization of clinically amyopathic dermatomyositis (CADM), the classification and diagnosis of its subtypes are still challenging. The aim of our study was to describe the clinicopathological features of CADM and assess the differences between amyopathic dermatomyositis (ADM) and hypomyopathic dermatomyositis (HDM).
METHODS: This retrospective study included 43 patients with CADM diagnosed at our institution from 2016 to 2020. Patients were subclassed into ADM (n = 30) and HDM (n = 13) groups to assess their clinicopathological differences.
RESULTS: All included patients had characteristic cutaneous manifestations of dermatomyositis; 67.4% had myositis-associated auto-antibodies, including ANA (32.6%), RNP (14.0%), anti-Ro52 (9.3%), anti-p155/140 (7.0%), rheumatoid factor (7.0%), anti-NXP-2 (4.7%), anti-MDA5 (2.3%), and anti-Jo-1 (2.3%) antibodies. One patient had associated interstitial lung disease, and another patient had oral squamous cell carcinoma. The histopathological findings included mucin deposition (69.8%), telangiectasia (65.1%), lymphocytic infiltrate (48.8%), vacuolar interface dermatitis (46.5%), and epidermal atrophy (14.0%). Compared to patients with HDM, ADM patients were significantly less likely to have epidermal atrophy, 3.3% versus 38.5% (p = 0.006), and more likely to have mucin deposition, 80.0% versus 46.2% (p = 0.028).
CONCLUSIONS: We described the clinicopathological features of CADM and highlighted the distinctions between ADM and HDM dermatopathologic findings. This information may prove helpful in diagnosing ambiguous lesions.
METHODS: This retrospective study included 43 patients with CADM diagnosed at our institution from 2016 to 2020. Patients were subclassed into ADM (n = 30) and HDM (n = 13) groups to assess their clinicopathological differences.
RESULTS: All included patients had characteristic cutaneous manifestations of dermatomyositis; 67.4% had myositis-associated auto-antibodies, including ANA (32.6%), RNP (14.0%), anti-Ro52 (9.3%), anti-p155/140 (7.0%), rheumatoid factor (7.0%), anti-NXP-2 (4.7%), anti-MDA5 (2.3%), and anti-Jo-1 (2.3%) antibodies. One patient had associated interstitial lung disease, and another patient had oral squamous cell carcinoma. The histopathological findings included mucin deposition (69.8%), telangiectasia (65.1%), lymphocytic infiltrate (48.8%), vacuolar interface dermatitis (46.5%), and epidermal atrophy (14.0%). Compared to patients with HDM, ADM patients were significantly less likely to have epidermal atrophy, 3.3% versus 38.5% (p = 0.006), and more likely to have mucin deposition, 80.0% versus 46.2% (p = 0.028).
CONCLUSIONS: We described the clinicopathological features of CADM and highlighted the distinctions between ADM and HDM dermatopathologic findings. This information may prove helpful in diagnosing ambiguous lesions.
摘要：
背景：尽管在临床肌病性皮肌炎（CADM）的分类方面取得了进展，其亚型的分类和诊断仍然具有挑战性.我们研究的目的是描述CADM的临床病理特征，并评估无肌病性皮肌炎（ADM）和低肌病性皮肌炎（HDM）之间的差异。
方法：这项回顾性研究包括2016年至2020年在我们机构诊断的43例CADM患者。将患者分为ADM（n=30）和HDM（n=13）组，以评估其临床病理差异。
结果：所有纳入的患者都有皮肌炎的特征性皮肤表现；67.4%有肌炎相关的自身抗体，包括ANA（32.6％），RNP（14.0%），反Ro52（9.3％），抗p155/140（7.0%），类风湿因子（7.0%），反恩智浦-2（4.7%），抗MDA5（2.3%），和抗Jo-1(2.3%)抗体。一名患者患有相关的间质性肺病，另一名患者患有口腔鳞状细胞癌。组织病理学发现包括粘蛋白沉积（69.8%），毛细血管扩张症(65.1%)，淋巴细胞浸润（48.8%），空泡界面皮炎（46.5%），和表皮萎缩（14.0%）。与HDM患者相比，ADM患者出现表皮萎缩的可能性明显较小，3.3%对38.5%(p=0.006)，更有可能有粘蛋白沉积，80.0%对46.2%(p=0.028)。
结论：我们描述了CADM的临床病理特征，并强调了ADM和HDM皮肤病理学发现之间的区别。这些信息可能有助于诊断模棱两可的病变。
方法：这项回顾性研究包括2016年至2020年在我们机构诊断的43例CADM患者。将患者分为ADM（n=30）和HDM（n=13）组，以评估其临床病理差异。
结果：所有纳入的患者都有皮肌炎的特征性皮肤表现；67.4%有肌炎相关的自身抗体，包括ANA（32.6％），RNP（14.0%），反Ro52（9.3％），抗p155/140（7.0%），类风湿因子（7.0%），反恩智浦-2（4.7%），抗MDA5（2.3%），和抗Jo-1(2.3%)抗体。一名患者患有相关的间质性肺病，另一名患者患有口腔鳞状细胞癌。组织病理学发现包括粘蛋白沉积（69.8%），毛细血管扩张症(65.1%)，淋巴细胞浸润（48.8%），空泡界面皮炎（46.5%），和表皮萎缩（14.0%）。与HDM患者相比，ADM患者出现表皮萎缩的可能性明显较小，3.3%对38.5%(p=0.006)，更有可能有粘蛋白沉积，80.0%对46.2%(p=0.028)。
结论：我们描述了CADM的临床病理特征，并强调了ADM和HDM皮肤病理学发现之间的区别。这些信息可能有助于诊断模棱两可的病变。
