Center for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Department of Dermatology, University of Lübeck, Lübeck, Germany.
JAMA Dermatol. 2016 Aug 1;152(8):897-904. doi: 10.1001/jamadermatol.2016.1099.
Anti-p200 pemphigoid is a rare subepidermal autoimmune blistering disease characterized by autoantibodies against a 200-kDa protein in the basement membrane zone. Anti-p200 pemphigoid is probably often misdiagnosed because of low availability of diagnostic assays and expertise and classified as bullous pemphigoid or epidermolysis bullosa acquisita.
To clinically characterize patients with anti-p200 pemphigoid, identified by using indirect immunofluorescence microscopy on skin substrates deficient in type VII collagen and laminin-332 (knockout analysis), to validate this technique by immunoblot with dermal extract, and to incorporate direct immunofluorescence serration pattern analysis in the diagnostic algorithm.
DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective study performed from January 2014 to June 2015 with biobank patient materials and clinical data for the period 1998 to 2015 from the single national referral center on autoimmune bullous diseases. Patients were selected based on a dermal side binding on 1-mol/L salt (sodium chloride)-split human skin substrate by indirect immunofluorescence microscopy, not diagnosed epidermolysis bullosa acquisita or anti-laminin-332 mucous membrane pemphigoid.
Indirect immunofluorescence microscopy knockout analysis was performed and diagnosis of anti-p200 confirmed by immunoblot with dermal extract. Clinical, histological, and immunological findings were registered. Autoantibodies against laminin γ1 were determined by immunoblot.
Twelve patients with anti-p200 pemphigoid (7 male and 5 female; mean age, 66.6 years) were identified using the indirect immunofluorescence microscopy knockout analysis. Direct immunofluorescence microscopy showed a linear n-serrated IgG deposition pattern along the basement membrane zone in 9 of 11 patients. The diagnosis was confirmed by immunoblot showing autoantibodies against 200-kDa protein in dermal extract in 12 of 12 patients. Autoantibodies against recombinant laminin γ1 were detected by immunoblot in 8 of 12 patients. Remarkable similarities were seen in clinical features with predominantly tense blisters on hands and feet, resembling dyshidrosiform pemphigoid. Mucosal involvement was seen in 6 (50%) of the patients.
Predominance of blisters on hands and feet may be a clinical clue to the diagnosis of anti-p200 pemphigoid. Direct immunofluorescence microscopy serration pattern analysis and indirect immunofluorescence microscopy knockout analysis are valuable additional techniques to facilitate the diagnosis of anti-p200 pemphigoid.
抗 p200 天疱疮是一种罕见的表皮下自身免疫性水疱病，其特征是基底膜带中存在针对 200kDa 蛋白的自身抗体。由于诊断检测和专业知识的可用性较低，抗 p200 天疱疮可能经常被误诊，并被归类为大疱性类天疱疮或获得性大疱性表皮松解症。
通过对缺乏 VII 型胶原和层粘连蛋白-332 的皮肤底物（敲除分析）进行间接免疫荧光显微镜检查，对抗 p200 天疱疮患者进行临床特征描述，并用皮肤提取物进行免疫印迹验证该技术，并将直接免疫荧光锯齿状模式分析纳入诊断算法。
设计、地点和参与者：这是一项回顾性研究，于 2014 年 1 月至 2015 年 6 月进行，使用单中心国家自身免疫性大疱病参考中心的生物库患者材料和 1998 年至 2015 年的临床数据。患者是基于间接免疫荧光显微镜在 1mol/L 盐（氯化钠）分裂的人皮肤底物上的真皮侧结合进行选择的，未被诊断为获得性大疱性表皮松解症或抗层粘连蛋白-332 黏膜天疱疮。
进行间接免疫荧光显微镜敲除分析，并通过皮肤提取物免疫印迹确认抗 p200 的诊断。记录临床、组织学和免疫学发现。通过免疫印迹确定针对层粘连蛋白γ1 的抗体。
使用间接免疫荧光显微镜敲除分析，鉴定出 12 例抗 p200 天疱疮患者（7 名男性和 5 名女性；平均年龄 66.6 岁）。11 例患者中有 9 例直接免疫荧光显微镜显示沿基底膜带线性锯齿状 IgG 沉积模式。12 例患者中的 12 例通过免疫印迹显示皮肤提取物中针对 200kDa 蛋白的自身抗体，从而确认了诊断。12 例患者中有 8 例通过免疫印迹检测到针对重组层粘连蛋白γ1 的抗体。在临床特征上，主要在手和脚上出现紧张性水疱，类似于汗疱疹样天疱疮，表现出显著的相似性。6 例（50%）患者存在黏膜受累。
在手和脚上出现水疱可能是诊断抗 p200 天疱疮的临床线索。直接免疫荧光显微镜锯齿状模式分析和间接免疫荧光显微镜敲除分析是有助于诊断抗 p200 天疱疮的有价值的附加技术。
