Non-scarring skin blistering disease and mucosal lesions with IgA autoantibodies reactive with collagen VII and IgG reactivity with laminin ?2
16.03.2012
Florea F, Torio-Padron N, Hashimoto T, Sitaru C.
Br J Dermatol. 2012; 167(4):938-41.
IgA form of epidermolysis bullosa aquisita (IgA-EBA) and anti-laminin 332 mucous membrane pemphigoid (L332-MMP) are two distinct autoimmune blistering diseases affecting mainly the skin and the mucous membranes respectively. We describe a unusual clinical constellation of linear deposition of IgA, IgG and complement at the epidermal basement membrane and in vivo epidermal nuclear IgG deposits. By indirect IF microscopy on 1M salt-split skin both IgA and IgG antibodies labelled the dermal side. Interestingly,further testing showed different specificities of the circulating autoantibodies. While IgA reacted with collagen VII, IgG showed reactivity with ?2 subunit of laminin 332. In addition, both circulating IgA and IgG antibodies showed nuclear staining on stratified epithelia in a nucleolar pattern, but had a low titre when tested on HEp2-cells. The unusual profile of the autoimmune response likely relates to the peculiar clinical features of the patient and may in particular explain the differential response to treatment.
