Pathogenesis is primarily an increase in proinflammatory cytokines IL-1 and TNF in the skin of PASH patients, possibly due to an increased number of CCTG repeats in the PSTPIP1 promoter region, a finding consistent PASH patients [118,119]. This evidence concerns the gene PSTPIP1 and Pyoderma gangrenosum-acne-suppurative hidradenitis syndrome.