Acute non-purulent inflammatory arthropathy associated with Staphylococcus aureus abscess

Case 1. A 20-year-old woman presented 4 weeks post-partum with widespread symmetrical inflammatory polyarthropathy with marked synovitis. Investigations revealed grossly raised CRP with negative immunology screen. A few days before presentation she saw her general practitioner with left-sided mastitis, which then developed into a Staphylococcus breast abscess. Surgical drainage of this led to almost immediate resolution of the joint complaints and return of CRP to normal. Case 2. A 27-year-old man developed widespread symmetrical inflammatory arthropathy. A few days prior to this he had developed folliculitis with a furuncle on his neck. Swab grew Staphylococcus aureus. His arthritis settled immediately following spontaneous drainage of his abscess and a full course of antibiotic. The pathogenic mechanism is unclear but could be toxin-mediated.