Biochip detection of BP180 autoantibodies in blister fluid for the serodiagnosis of bullous pemphigoid: A pilot study

Bullous pemphigoid is an autoimmune subepidermal blistering skin disease immunologically defined by autoantibodies directed against basement membrane zone antigens, the main of which is BP180. Laboratory tests are essential for diagnosis and include direct immunofluorescence and serologic assessments with indirect immunofluorescence and ELISA. Serology may be performed on blister fluid, in alternative to blood serum. This study investigated the use of a Biochip-based indirect immunofluorescence approach for the serum diagnosis of bullous pemphigoid on blister fluid. We compared the results using the Biochip-method with the ELISA detection of bullous pemphigoid-180 autoantibodies in blister fluid and observed a perfect correlation between these 2 methods in our group of 13 patients with clinical and direct immunofluorescence diagnosis of bullous pemphigoid. The Biochip is a simple, standardized and inexpensive diagnostic tool and its use on blister fluid may facilitate the diagnosis of this and other autoimmune bullous disorders. Our results suggest that the Biochip assay on serum of bullae is a non-invasive screening technique for the early diagnosis of bullous pemphigoid that is practical for fragile elderly patients and achievable even in small laboratory settings.