Immunofuorescence in Various Skin Diseases

Immunofluorescence (IF) is a technique widely used both to investigate pathophysiology and to help in the accurate diagnosis of various cutaneous disorders, especially bullous diseases and connective tissue diseases. IF testing is invaluable in confirming a diagnosis that is suspected by clinical or histologic examination. Direct immunofluorescence (DIF) is performed on perilesional skin for patients with bullous disease and lesional skin for patients with connective tissue diseases and vasculitis. It helps detect molecules such as immunoglobulins and complement components within biopsy specimen. Indirect immunofluorescence (IIF) is used to detect circulating autoantibodies in patient’s serum. It is helpful in confirming a suspected diagnosis as well as in differentiating among closely related bullous diseases. Many years after the discovery of autoantibodies in autoimmune bullous diseases, direct and indirect immunofluorescence still remain an essential armamentarium for their diagnosis and management. Moreover, thanks to the advent of these techniques and their immunologic and molecular findings, new diseases have been defined and continue to be defined. In conclusion, IF studies have now become an invaluable supplement to clinical and histological examination in a variety of skin diseases and have also enabled the development of new techniques such as immunoblotting, enzyme-linked immunosorbent assay (ELISA), and Biochip method.