Costimulation pathway blockade in kidney transplant recipients with de-novo rheumatoid arthritis.

The best approach to treatment of de-novo rheumatoid arthritis in solid organ transplant recipients on typical immunosuppression is not well established. The use of biologics targeting specific cell types, cytokines, and immunological pathways has been gaining interest in the treatment of both, auto- and alloimmunity. We present a case of de-novo rheumatoid arthritis in a kidney transplant recipient 10 years post-transplant while receiving cyclosporine, mycophenolate mofetil, and also prednisone. Initial presentation included features of polymyalgia rheumatica and nephrotic range proteinuria. Kidney biopsy showed membranous nephropathy. The patient was initially treated with methotrexate, while mycophenolate mofetil was discontinued. Clinical symptoms improved, but creatinine significantly increased, which led to discontinuation of methotrexate and mycophenolate mofetil was restarted. The kidney function improved, but the patient experienced a flare of rheumatoid arthritis. Costimulatory blocker, abatacept, was initiated and cyclosporine was gradually tapered off. Graft function remained stable for a follow-up period of 7 years. Joint pain, weakness, and stiffness resolved. Follow-up plain film radiographs at 5 years post initial presentation showed no new joint erosions in hands or feet. Costimulatory blockers may broaden the therapeutic choices of transplant recipients with de-novo autoimmune diseases.