OBJECTIVE: To describe a nonconventional diagnostic technique used to diagnose a case of cicatrizing conjunctivitis associated with epidermolysis bullosa acquisita. METHODS: Direct immunofluorescence of a biopsy specimen of the patient's conjunctiva was performed using fluorescein-conjugated rabbit antihuman antibodies against IgA, IgG, and IgM; complement C3; and fibrinogen. Immunoblot assay using healthy human skin as substrate was performed to investigate for the presence of antibodies in the patient's serum. After the diagnosis of systemic autoimmune disease was established, intravenous immunoglobulin therapy was administered. RESULTS: Direct immunofluorescence of the conjunctiva revealed linear deposition of IgA and IgG, and C3 at the epithelial basement membrane zone. Immunoblot analysis demonstrated the presence of IgG antibodies in patient serum directed against a 290-kDa protein in human skin. A diagnosis of epidermolysis bullosa acquisita was established. All signs and symptoms improved dramatically 4 months after initiation of intravenous immunoglobulin therapy and remained stable during follow-up. CONCLUSIONS: Epidermolysis bullosa acquisita can manifest in the eye as chronic cicatrizing conjunctivitis indistinguishable from ocular cicatricial pemphigoid. A nonconventional diagnostic tool (immunoblot assay) might be helpful in establishing the diagnosis of an underlying systemic autoimmune disease in patients with chronic cicatrizing conjunctivitis. Intravenous immunoglobulin therapy was effective against chronic cicatrizing conjunctivitis associated with epidermolysis bullosa acquisita.