MedGen

Pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) is a rare autosomal dominant autoinflammatory disease that typically presents with recurrent sterile, erosive arthritis in childhood, occurring spontaneously or after minor trauma, occasionally resulting in significant joint destruction. By puberty, joint symptoms tend to subside and cutaneous symptoms predominate, including pathergy, frequently with abscesses at the sites of injections, severe cystic acne, and recurrent nonhealing sterile ulcers, often diagnosed as pyoderma gangrenosum (summary by Demidowich et al., 2012). [from OMIM]

Acute febrile neutrophilic dermatosis (AFND) is an autosomal dominant autoinflammatory disorder characterized by onset of recurrent fever and dermatologic abnormalities in childhood. Laboratory studies show elevated acute-phase reactants and activation of the inflammatory response, particularly IL1B (147720). Additional more variable features may include myalgia and arthralgia (summary by Masters et al., 2016). [from OMIM]