Human orf complicated by epidermolysis bullosa acquisita

Orf is a DNA parapoxvirus transmitted to humans by contact with infected goats and sheep. Many complications have been reported after orf infection, including erythema multiforme. A few cases of autoimmune bullous dermatosis complicating orf disease have been reported to date. They are usually characterized by tense blister eruptions with or without mucosal involvement; linear deposition of C3, IgG and/or IgA along the basement membrane; and negativity of indirect immunofluorescence analysis and enzyme-linked immunosorbent assay (ELISA) (performed in four of 11 reported cases). These analyses have targeted antigens of bullous pemphigoid, mucous membrane pemphigoid or epidermolysis bullosa acquisita, except one case of mucosal pemphigoid with antilaminin-332 antibodies. We describe the case of a patient who presented with an ulceration on his finger 10 days after direct contact with a lamb during Eid al-Adha. Four weeks later he developed a severe tense blistering eruption associated with mucous membrane erosions. Indirect immunofluorescence analysis using the patient's serum revealed circulating antibasement membrane IgG that bound the dermal side of salt-split skin. ELISA was positive for recombinant immunodominant NC1 domain of type VII collagen. We finally diagnosed epidermolysis bullosa acquisita complicating probable human orf infection.