Pyogenic Arthritis, Pyoderma Gangrenosum, Acne, Suppurative Hidradenitis (PA-PASH) Syndrome: An Atypical Presentation of a Rare Syndrome.

BACKGROUND Pyogenic arthritis, pyoderma gangrenosum (PG), acne, and suppurative hidradenitis (PA-PASH) syndrome has been linked to an auto-inflammatory pathway. We report a case that is an atypical presentation of a rare syndrome, which supports literature suggesting that different phenotypes of PG-related syndromes may be a variation of the same pathogenic spectrum. Interestingly, our patient displayed a positive proteinase-3 antibody (PR-3).