Successful Switch to Golimumab for Eosinophilia and Skin Symptoms Related to Multiple Biologics in a Patient with Rheumatoid Arthritis

Biologics used in the treatment of rheumatoid arthritis (RA) rarely cause eosinophilia. We herein report a patient with RA being treated with infliximab, adalimumab, and tocilizumab who developed eosinophilia with skin symptoms. Interestingly, the marked eosinophilia and skin symptoms did not reappear after the patient's medication was switched to golimumab. In this case, the presence of biologics-specific antibodies suggested that immunogenicity caused the eosinophilia. Therefore, switching to a biologic with a lower immunogenicity was effective. These findings may be helpful for clinicians treating patients with biologics-induced eosinophilia.