Sapho Syndrome, also known as synovitis-acne-pustulosis-hyperostosis-osteitis syndrome, is related to spondylarthropathy and synovitis. An important gene associated with Sapho Syndrome is PSTPIP2 (Proline-Serine-Threonine Phosphatase Interacting Protein 2), and among its related pathways/superpathways are Innate Immune System and Cytokine Signaling in Immune system. The drugs Etanercept and Immunologic Factors have been mentioned in the context of this disorder. Affiliated tissues include skin and bone, and related phenotypes are arthralgia and chest pain