Dermatology Clinic, University of Catania, Catania, Italy.
Department "G.F. Ingrassia", Section of Anatomic Pathology, University of Catania, Catania, Italy.
PLoS One. 2021 Mar 10;16(3):e0247835. doi: 10.1371/journal.pone.0247835. eCollection 2021.
Dilated and tortuous vessels within elongated dermal papillae represent a histopathological clue of psoriasis. However, the number of dilated capillaries (capillary density) in psoriasis remains undefined as the results from the available studies differ significantly.
To evaluate the capillary density in psoriasis using dermoscopy and horizontal histopathological sections (HHS), two techniques that share the horizontal view of the skin, and to compare the results with the existing data.
Twenty adult patients with stable plaque psoriasis were enrolled and, in each patient, a target area of the examined plaque, previously engraved by gently rotating a 5-mm biopsy punch device, underwent dermoscopy and biopsy for HHS. In all examined fields, capillary density was evaluated in a centered 4-mm diameter area, counting the number of red dots at dermoscopy and of dermal papillae at HHS.
A total of 20 target lesions located on the trunk, arms and tights were evaluated. The mean capillary density resulting from dermoscopy was 43.02±6.60/mm 2 whereas that from HHS was 50.30±9.05/mm 2. These data showed a statistically significant difference (p = 0.006), with a strong correlation at Pearson's test (r = 0.88).
Our results when compared with those from the existing literature showed some differences. The peculiarity of our work is represented by the precise measurement and correlation of the capillary density using two different methods, as the preliminary skin engraving allowed a perfect match between the area undergoing dermoscopy and that of skin sampling for HHS. Compared to dermoscopy in which deep-located vessels might have gone undetected, HHS seems to reflect more precisely and reliably the real capillary density showing an average of 50 capillaries/mm 2 that in a common 5x5 cm psoriatic patch corresponds to an average of 125.000 capillaries. These results highlight the extraordinary potential of psoriatic skin to develop such a complex and intricate vascular network.
真皮乳头中扩张和扭曲的血管是银屑病的组织病理学线索。然而，由于现有研究的结果差异很大，银屑病中扩张的毛细血管（毛细血管密度）的数量仍然没有定义。
使用皮肤镜和水平组织学切片（HHS）评估银屑病的毛细血管密度，这两种技术具有相同的皮肤水平视野，并将结果与现有数据进行比较。
招募了 20 名成人斑块型银屑病患者，在每位患者的受检斑块上，用轻轻旋转 5mm 活检打孔器装置预先刻上标记，进行皮肤镜和 HHS 活检。在所有检查的视野中，在中心 4mm 直径的区域评估毛细血管密度，在皮肤镜下计数红点的数量，在 HHS 下计数真皮乳头的数量。
共评估了 20 个位于躯干、手臂和下肢的靶病变。皮肤镜检查的平均毛细血管密度为 43.02±6.60/mm 2 ，HHS 为 50.30±9.05/mm 2 。这些数据显示出统计学上的显著差异（p = 0.006），Pearson 检验显示相关性很强（r = 0.88）。
与现有文献相比，我们的结果存在一些差异。我们工作的特点是使用两种不同的方法精确测量和相关毛细血管密度，因为皮肤的初步雕刻允许皮肤镜检查的区域与 HHS 皮肤取样的区域完全匹配。与可能未检测到深部血管的皮肤镜检查相比，HHS 似乎更能准确可靠地反映真实的毛细血管密度，显示平均 50 个/mm 2 的毛细血管，在一个常见的 5x5cm 银屑病斑块中，相当于平均 125000 个毛细血管。这些结果突出了银屑病皮肤形成如此复杂和错综复杂的血管网络的非凡潜力。
