Bullous Pemphigoid, Mucous Membrane Pemphigoid, and Epidermolysis Bullosa Acquisita

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Bullous Pemphigoid, Mucous Membrane Pemphigoid, and Epidermolysis Bullosa Acquisita



This chapter, in addition to Chapters 23 and 25, cover the autoimmune bullous diseases. The concepts of direct immunofluorescence (DIF) and indirect immunofluorescence (IIF) are reviewed in Chapter 23 (see Fig. 23.2), as are the recommended sites for performing skin biopsies for DIF (see Fig. 23.1).



Bullous Pemphigoid (BP)



Immunobullous disease due to circulating autoantibodies that bind two components of hemidesmosomes, i.e. structures that provide adhesion between the epidermis and the dermis; the two antigens are collagen XVII (also referred to BP antigen 2 [BPA2] or BP180) and BPA1/BP230.


Occurs more commonly in the elderly and can be drug-induced (e.g. furosemide); rarely, lesions are induced by ultraviolet light or radiation therapy.


Both pruritic fixed urticarial plaques and tense bullae are seen (Figs. 24.1 and 24.2); the latter can develop within normal skin or areas of erythematous skin and produce erosions when they rupture; oral lesions are much less common than in pemphigus vulgaris (10–30% of patients).




Pruritus and nonspecific eczematous (see Fig. 24.1D) or papular lesions can precede the more characteristic cutaneous lesions and may be the predominant finding; unusual variants include dyshidrosiform (palms and soles), vegetans (major body folds), and localized (e.g. pretibial in adults; vulvar in children, acral in infants), as well as those that mimic prurigo nodularis and toxic epidermal necrolysis (Fig. 24.3).



Histologically, a subepidermal bulla plus an infiltrate of eosinophils is seen when the lesions are bullous; DIF demonstrates immunodeposits of IgG and/or C3 in a linear array along the basement membrane zone (see Fig. 23.3B); in general, by salt-split skin immunofluorescence studies, the immunodeposits are in the roof (epidermal side) of the blister (Fig. 24.4).


Apr 22, 2016 | Posted by in Dermatology | Comments Off on Bullous Pemphigoid, Mucous Membrane Pemphigoid, and Epidermolysis Bullosa Acquisita

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