A case report of a boy with juvenile idiopathic arthritis since the age of 2 years, generalized onset, complicated by nephrotic syndrome due to secondary type A amyloidosis is presented. In the patient the disease had an especially severe course, complicated by frequent infections, making routine treatment difficult. Amyloidosis was diagnosed in the 5(th) year of the disease based on a rectal biopsy. Since the disease onset the boy has been taking prednisolone and sequentially cyclosporine A, methotrexate, chlorambucil, etanercept, and cyclophosphamide. Clinical and laboratory remission was observed after treatment with tocilizumab. After 42 months of treatment with tocilizumab the boy's condition is good. There is no pain or joint edema, and no signs of nephrotic syndrome.