Linear IgA bullous disease limited to the eye: A diagnostic dilemma - Response to intravenous immunoglobulin therapy

Purpose: To report on a diagnostic dilemma and treatment challenge in a pat ient with chronic cicatrizing conjunctivitis without involvement of skin an d other mucous membranes persisting for 6 years and not responding to topic al and systemic steroids. Design: interventional case report. Methods: We performed direct immunofluorescence of the conjunctiva with flu orescein-conjugated rabbit antihuman antibodies against immunoglobulin A, G , and M, complement 3 component, and fibrinogen. To investigate the presenc e of circulating antibodies in patient's serum, indirect immunofluorescence using normal human conjunctiva, normal human skin, and monkey esophagus as substrate was done. In addition, we did immunoblot. analysis using normal human epidermis as substrate to determine the molecular weight of an antige n. The patient was treated with intravenous immunoglobulin (IVIg). The corr elation between the titer of circulating antibodies and the activity of con junctival inflammation at various intervals during the course of IVIg thera py was demonstrated by immunoblot assay with serial dilutions of the patien t's serum. The highest dilution at which the binding was visible was consid ered the titer. Results: Direct immunofluorescence of the conjunctiva and indirect immunofl uorescence with both salt split skin and conjunctiva as substrate disclosed linear deposition of immunoglobulin A (IgA) at the epithelial basement mem brane. Immunoblot analysis demonstrated the presence of IgA circulating ant ibodies in patient's serum directed against a 97kDa protein in human epider mis. A continuous decrease in the titer of these antibodies correlating to improvement of clinical symptoms was observed during IVIg therapy. Conclusions: Use of a nonconventional diagnostic tool (immunoblot analysis) , in addition to conventional immunohistologic studies, might be helpful in establishing the diagnosis of patients with chronic cicatrizing conjunctiv itis. On the basis of results of these laboratory tests and clinical presen tation, we believe that this patient has linear IgA bullous disease limited to the eye. IVIg therapy decreased the titer of circulating antibodies and induced a remission in this patient. Ophthalmology 2000; 107:1524-1528 (C) 2000 by the American Academy of Ophthalmology.