Abstract

In its strict sense, the term "autoinflammatory syndromes" comprises the hereditary periodic fever syndromes (HPF), which are caused by mutations of pattern-recognition receptors (PRR) and perturbations of the cytokine balance. These include the crypyrinopathies, familial Mediterranean fever, TNF-receptor associated periodic fever syndrome (TRAPS), hyper-IgD and periodic syndrome (HIDS), pyogenic sterile arthritis, pyoderma gangrenosum and acne (PAPA) syndrome, NALP12-HPF, and the Blau syndrome. The diseases are characterized by spontaneous activation of cells of the innate immunity in the absence of ligands. Autoantibodies are usually not found. HPF clinically present with recurrent fever episodes and inflammation, especially of serosal and synovial interfaces and the skin. Intriguingly, PRR-mediated autoinflammtory mechanisms also play a role in a number of chronic inflammatory and autoimmune diseases.