Rapid decrease of serum hepcidin-25 in 6 MCD patients treated with tocilizumab during 14-day short-term course. Administration of tocilizumab resulted in down-regulation of the serum hepcidin level in 6 of 6 MCD cases. (Left panel) In all cases except case V, rapid reduction of serum hepcidin-25 was observed on days 1 or 4 after the initial dose of tocilizumab, followed by reductions in CRP and improvement in Hb levels. (Table) Hb, the serum values of hepcidin-25, CRP, IL-6, and MCV in MCD patients before and after 14 days of therapy with tocilizumab. (Right panel) In case V, the initial hepcidin level was extremely high (256 ng/mL), and it decreased only slightly after tocilizumab administration.