Excess Serum Interleukin‐18 Distinguishes Patients with Pathogenic Mutations in PSTPIP1

Dominantly inherited PSTPIP1 mutations cause a spectrum of autoinflammatory manifestations epitomized by PAPA syndrome (pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome.). The connections between PSTPIP1 and PAPA syndrome are poorly understood, although evidence suggests involvement of pyrin inflammasome activation. Interleukin‐18 (IL‐18) is an inflammasome‐activated cytokine associated with susceptibility to macrophage activation syndrome (MAS). This study was undertaken to investigate an association of IL‐18 with PAPA syndrome.