Cutaneous Immunofluorescence IgG Antibody

This test is used to detect circulating autoantibodies against epithelial cell surface and basement membrane zone antigens, aiding in the diagnosis and differentiation of autoimmune bullous diseases. Detection of anti-skin antibodies, both epithelial cell surface and basement membrane zone, plays an important role in diagnosing and sometimes assessing prognosis in autoimmune bullous diseases such as pemphigus, pemphigoid, cicatricial pemphigoid, anti Laminin 332 autoimmunity, epidermolysis bullosa acquisita (EBA), and bullous lupus erythematosus (LE). Epithelial cell surface antibodies are highly specific for pemphigus and are present in more than 90% of patients with active disease. Basement membrane antibodies occur in approximately 70% of active bullous pemphigoid cases, 50% of EBA cases and about 10% of cicatricial pemphigoid cases. EBA can closely resemble bullous pemphigoid clinically, histologically and immunologically. Indirect immunofluorescence on salt split skin helps differentiate these conditions by identifying whether antibodies bind to the epidermal roof or dermal floor of the split at the lamina lucida. This test, along with additional follow-up assays, is essential for distinguishing EBA, bullous LE and cicatricial pemphigoid from bullous pemphigoid.