A case of autoinflammatory skin and bone disease flared by a change in osteoporosis management

IL: interleukin NR: normal range PAPA: pyogenic sterile arthritis, pyoderma gangrenosum, and acne PTH: parathyroid hormone SAPHO: synovitis, acne, pustulosis, hyperostosis, and osteitis WBC: white blood cell INTRODUCTION Autoinflammatory syndromes are an incompletely understood spectrum of diseases that involve spontaneous inflammation caused by genetic variants of the innate immune system. Unlike autoimmune diseases, no high-titer autoantibodies are associated with the disease process. We report a case of autoinflammatory skin and bone disease that flared within 1 month of replacing alendronate with teriparatide therapy. Teriparatide, a recombinant form of parathyroid hormone (PTH), is used for the treatment of osteoporosis and may be prescribed for dermatology patients requiring long-term prednisone therapy. Bisphosphonates such as alendronate are used to treat osteoporosis and autoinflammatory disease; they possess anti-inflammatory properties and the ability to remodel bone. We hypothesize that replacing alendronate with teriparatide triggered this disease flare through stimulatory effects on inflammatory cytokines, specifically interleukin (IL)-1 and recommend caution when choosing a drug to treat osteoporosis in patients with autoinflammatory skin and bone disorders.