Papa Syndrome

Abstract

The pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome was first recognized in 1997 when ten family members in three generations manifested with variable expression of juvenile-onset arthritis and subsequent presentation of pyoderma gangrenosum and cystic acne in adolescence and adulthood [1]. This inherited disorder stems from dysregulation of the innate immune system, presenting with symptoms of seemingly unprovoked episodes of synovial tissue and skin infl ammation [1]. Recurrent infl ammation seen in PAPA syndrome typifies that classically seen in autoinfl ammatory disorders. Autoinfl amatory disorders, though lacking clear diagnostic criteria, are marked by chronic and intermittent episodes of fever, cytokine dysregulation, and organ inflammation; skin and joint involvement is a prominent feature [2,3]. Unlike autoimmune diseases, autoinfl ammatory disorders lack high-titer autoantibodies and autoreactive T lymphocytes [2]. Genes associated with inherited syndromes of autoinfl ammation encode for protein mediators of apoptosis, inflammation, and cytokine processing (Table 20.1) [3].