Esophag cell surface IgA

Laboratory assay overview

This test is intended for confirmation of IgA antibody presence to aid in the diagnosis of pemphigoid, pemphigus, epidermolysis bullosa acquisita and bullous lupus erythematosus. IgA antibodies directed against the basement membrane zone (BMZ) are produced in pemphigoid. When serum contains anti-BMZ antibodies, the fluorescence pattern on sodium chloride (NaCI)-split skin substrate assists in differentiating pemphigoid from epidermolysis bullosa acquisita (EBA) and bullous lupus erythematosus (LE). Fluorescence on the roof (epidermal side) or on both epidermal and dermal sides of the split indicates pemphigoid, whereas fluorescence restricted to the dermal side is consistent with EBA or bullous LE. Additionally, patients with pemphigus produce IgA epidermal cell antibodies. The titer of epidermal cell surface (Intercellular) antibodies generally correlates with pemphigus disease activity.