Abstract
A 55-year-old woman had been treated for rheumatoid arthritis with tocilizumab 1 month prior to the onset of mild abdominal
pain. Computed tomography revealed swelling of the appendix and ascites around the appendix. She was diagnosed with acute
appendicitis and underwent emergency surgery. Although her symptoms and laboratory data indicated mild infection, surgery
was conducted because of the computed tomography findings and because we believed that the physical findings and laboratory
data were not dependable due to the tocilizumab.
Upon surgery, a perforated inflamed appendix and abscess formation around the appendix were confirmed. Tocilizumab,
which is relatively new, may conceal signs of infection or dull response to tests such as the Blumberg sign for peritonitis. It should
be widely noted that the physical findings and laboratory data of patients with abdominal distress under tocilizumab treatment
may be misleading.
