A CLINICAL CASE OF SYSTEMIC JUVENILE ARTHRITIS COMPLICATED BY RECURRENT MACROPHAGE ACTIVATION SYNDROME AND CHRONIC OSTEOMYELITIS OF THE CLAVICLE

The paper describes a clinical case of severe systemic juvenile idiopathic arthritis (JIA) in a child with an early disease onset, which is resistant to multicomponent therapy (glucocorticoids, methotrexate, the tumor necrosis factor-α inhibitor etanercept), and the successful use of the anti-interleukin 6 receptor monoclonal antibody tocilizumab with the achievement of sustained (30-month) drug remission. The therapy with tocilizumab was accompanied by unpredictable adverse events (chronic osteomyelitis of the clavicle, macrophage activation syndrome) and their timely treatment permitted avoidance of life-threatening consequences. The presented case shows difficulties in the follow-up of patients with systemic JIA in clinical practice, requiring alertness to the risk of infectious complications and development of macrophage activation syndrome.