A number of puzzling autoimmune syndromes has recently been clustered around the same immunological feature: infiltration of tissue by IgG4 producing plasma cells. Collectively these diseases are called the IgG4 related diseases (IgG4-RD). Despite recent advances in understanding these diseases, making the diagnosis is challenging as invasive diagnostic procedures and specific tests are required. Nevertheless, diagnosing IgG4-RD is rewarding as these diseases are often mistaken for malignancy. In this presentation we will discuss several cases to demonstrate the challenges in the diagnostic process.
Disclosure of Interest None declared