A case of pelvic abscess following total laparoscopic hysterectomy during Tocilizumab administration

Abstract

　Tocilizumab (TCZ) is a humanized anti-human IL-6 receptor monoclonal antibody that suppresses the signaling of IL-6, which is important for inflammation and immune activation. In Japan, the use of TCZ for treatment of rheumatoid arthritis (RA), Castleman's disease, juvenile idiopathic arteritis, and Takayasu's arteritis / giant cell arteritis, etc. has been approved. IL-6 inhibition of TCZ suppresses leukocyte infiltration into the inflamed area. In addition, when TCZ achieves an effective blood concentration, C-reactive protein (CRP) becomes negative regardless of clinical presentation. Inflammatory outcomes such as CRP and erythrocyte sedimentation rate may be significantly different from clinical symptoms. We report a case of pelvic abscess following a laparoscopic simple total hysterectomy and bilateral salpingectomy during TCZ administration, along with a review of literature.