トシリズマブ投与後に重度の肝機能障害を来した2例

Severe Liver Function Disorder after Tocilizumab Therapy. Reports of Two Cases

　関節リウマチおよび混合性結合組織病の症例に対してトシリズマブの投与を行い，投与開始後に肝機能障害を来した2例を経験した．2例とも重度肝機能障害を来しうる薬剤を併用中であり，併用薬剤による肝機能障害と診断したが，IL-6の肝臓保護作用を考慮すると，トシリズマブ投与により薬剤性肝機能障害が惹起された可能性も否定し得なかった．トシリズマブ投与時は肝炎ウイルスの活性化だけではなく薬剤性肝機能障害の発症にも注意すべきであると思われた．

　We report two cases of liver function disorder in patients being treated with tocilizumab, one in a rheumatoid arthritis patient and the other in a mixed connective tissue disease patient.　Both patients were being treated with other drugs in combination that are capable of inducing severe liver function disorders, and we suspected that the liver function disorder was a side effect of one of the other drugs, not tocilizumab, but in view of the protective effect of IL-6 on the liver, we could not rule out the possibility that the severe liver function disorder was induced by tocilizumab.　Greater attention should be paid not only to activation of hepatitis virus in patients being treated with tocilizumab but to liver function disorders as well.