Baltazard T, Dhaille F, Duvert-Lehembre S, Lok C, Chaby G
Department of Dermatology, Hôpital Nord, University of Amiens, Amiens, France.
Dermatol Online J. 2017 Aug 15;23(8):13030/qt9gv0j00w.
Linear IgA bullous dermatosis (LABD) is an autoimmune blistering skin disorder characterized by linear IgA deposits along the dermoepidermal junction. Usually idiopathic, LABD can be drug-induced.
To report the atypical characteristics of a case of trimethoprim-sulfamethoxazole-induced LABD presenting as toxic epidermal necrolysis (TEN).
A 63-year-old woman treated with trimethoprim-sulfamethoxazole for Pneumocystis jirovecii infection developed a generalized maculopapular rash with herpetiform lesions, rosette-like lesions, and tense bullae with Nikolsky sign.
Anti-basement membrane zone antibodies were negative, but immunoblot revealed a 160 kDa band corresponding to subepidermal class IgA desmoglein 1. Skin biopsy specimens revealed a subepidermal bulla and direct immunofluorescence showed linear IgA deposition along the basement membrane zone. A diagnosis of toxic epidermal necrolysis was excluded and replaced by trimethoprim-sulfamethoxazole-induced LABD.
We report a case of trimethoprim-sulfamethoxazole-induced LABD with a 160 kDa IgA desmoglein 1 found by immunoblotting analysis, probably by epitope spreading.
线状IgA大疱性皮肤病（LABD）是一种自身免疫性水疱性皮肤病，其特征为沿真皮表皮交界处有线状IgA沉积。LABD通常为特发性，也可由药物引起。
报告一例甲氧苄啶-磺胺甲恶唑诱发的LABD表现为中毒性表皮坏死松解症（TEN）的非典型特征。
一名63岁女性因耶氏肺孢子菌感染接受甲氧苄啶-磺胺甲恶唑治疗，出现全身性斑丘疹，伴有疱疹样损害、玫瑰花结样损害及紧张性大疱，有尼氏征。
抗基底膜带抗体阴性，但免疫印迹显示一条160 kDa条带，对应表皮下类IgA桥粒芯糖蛋白1。皮肤活检标本显示表皮下水疱，直接免疫荧光显示沿基底膜带有线状IgA沉积。排除中毒性表皮坏死松解症的诊断，改为甲氧苄啶-磺胺甲恶唑诱发的LABD。
我们报告一例甲氧苄啶-磺胺甲恶唑诱发的LABD，通过免疫印迹分析发现有160 kDa IgA桥粒芯糖蛋白1，可能是由于表位扩展。
