Divisão de Clínica Dermatológica, do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil.
Scientific researcher VI of Laboratório de Investigação Médica, Imunodermatologia, Instituto de Saúde da Secretaria de Estado da Saúde do Estado de São Paulo, do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil.
Int J Dermatol. 2018 Jun;57(6):707-712. doi: 10.1111/ijd.13926. Epub 2018 Jan 31.
Histoid leprosy (HL) is a rare form of lepromatous leprosy, characterized by hyperchromic indurated nodules above normal skin. Its main histopathological aspect is spindle cells. Because it may simulate other aspects, such as dermatofibroma and neurofibroma, histoid leprosy poses itself as a diagnostic challenge.
This is a retrospective study with all patients having been selected from the leprosy clinic of the Hospital das Clínicas da Universidade de São Paulo from 2006 to 2016.
There were 12 patients in this study, eight in the histoid group and four in the lepromatous leprosy group. The prevalence of HL was 1.12% in all leprosy subjects. All individuals from HL group were "de novo" cases, and the histopathological analysis of skin lesions presented spindle cells generating a storiform pattern. Immunohistochemistry for CD68, vimentin, and anti-BCG were positive in all 12 cases. Factor XIIIa was visualized only in the papillary dermis, and S100 protein was negative in all biopsies. Smooth-muscle actin was present in 62.5% of the HL samples.
The prevalence of HL was similar to previous reports. However, all histoid patients were "de novo" cases, differing from published studies. Fusocellular macrophage transformation could be explained by the differences in cytoskeleton proteins expressed in histoid lesions in comparison to other leprosy variants, with emphasis on vimentin and smooth muscle actin.
组织细胞样麻风（HL）是一种罕见的瘤型麻风，其特征是在正常皮肤上方出现色素沉着的硬结性结节。其主要组织病理学特征是梭形细胞。由于它可能模拟其他方面，如皮肤纤维瘤和神经纤维瘤，组织细胞样麻风构成了诊断上的挑战。
这是一项回顾性研究，所有患者均选自 2006 年至 2016 年期间圣保罗大学临床医院的麻风诊所。
本研究共有 12 例患者，其中 8 例为组织细胞样组，4 例为瘤型麻风组。HL 在所有麻风患者中的患病率为 1.12%。HL 组的所有个体均为“初发”病例，皮肤病变的组织病理学分析显示梭形细胞产生了束状模式。12 例患者的 CD68、波形蛋白和抗 BCG 的免疫组化均为阳性。组织 XIIIa 仅在乳头真皮中可见，所有活检均未见 S100 蛋白。平滑肌肌动蛋白存在于 62.5%的 HL 样本中。
HL 的患病率与以往报道相似。然而，所有组织细胞样患者均为“初发”病例，与已发表的研究不同。梭形细胞巨噬细胞转化可能是由于组织细胞样病变中细胞骨架蛋白的表达与其他麻风变体不同所致，其中波形蛋白和平滑肌肌动蛋白尤为重要。
