Figure 1.
Kinetics of biochemical variables during treatment.
The patient began receiving methylprednisolone sodium succinate at a dose of 1 g/day for 1 day, followed by a dose of 200 mg/day with initial improvement of biochemical variables. Despite receiving high doses of methylprednisolone, the patient had an immune flare associated with a rapid increase in ferritin and troponin T levels. Tocilizumab (TCZ) at a dose of 8 mg/kg was administrated on days 7 and 14. This resulted in a rapid decrease of troponin T and I, creatine kinase (CK) and ferritin levels as well as inflammatory parameters and was associated with the resolution of the myocarditis and myositis, according to clinical and biochemical measures. The patient was then progressively weaned from corticosteroids and did not experience any recurrence of cardiac, myositis or hemophagocytic syndrome adverse events. ‡High-sensitivity troponin T is expressed by skeletal muscle, including regenerating skeletal muscle tissue, whereas high-sensitivity troponin I is specific to the myocardium.3,13 As reported previously,3 given that the patient had severe myositis related to immunotherapy, the high-sensitivity troponin T concentration reflected active skeletal muscle regeneration rather than active myocarditis in the context of normalization of the high-sensitivity troponin I concentration and CK level.3 hs, high-sensitivity; i.v., intravenous; MP, methylprednisolone sodium succinate pulse; PDN, prednisone; us, ultrasensitivity.