Immune-mediated inflammatory diseases (IMIDs) characterized by three nosological entities, autoimmune diseases, autoinflammatory diseases and inflammatory diseases of undetermined mechanism, share in common the inflammatory process but their clinical and biological expressions are extremely diverse. Epidemiological and clinical studies of IMIDs are mostly partial and non-exhaustive. Affections that constitute IMIDs are characterized by chronic inflammatory processes. All these affections are classified based on their immunogenetic, pathophysiological, and clinical profiles. It is well understood that similar therapeutic targets as well as prevention and treatment strategies can be developed for IMIDs with the same immunogenetic, pathophysiological, and clinical profiles. This work presents an immunogenetic, pathophysiological, and clinical classification, now especially integrating epidemiological data (rare <1/2000; common ≥1/2000). To achieve this, a literature review was also necessary to refine the classification by adding the epidemiological data (rare <1/2000; common ≥ 1/2000). This work highlights the comprehensive distribution of IMIDs through an immunogenetic, pathophysiological, and clinico-epidemiological classification.