Tocilizumab (TCZ) is a humanized antihuman interleukin-6 (IL-6) receptor antibody used for the treatment of inflammatory diseases such as rheumatoid arthritis (RA). While TCZ could act as a therapeutic agent, it has a potential for inducing adverse drug events including psoriasis-like eruption. Seven cases with specific reference to TCZ-induced psoriasis eruption have been reported worldwide so far. In these cases, treatments with the same dosage of TCZ were either maintained or discontinued. Herein, we report a case involving a 74-year-old man diagnosed with rheumatoid factor-positive and anti-citrullinated protein antibody-positive RA with comorbidity of atopic dermatitis. TCZ was administered intravenously with oral methotrexate. After the third infusion, the patient developed TCZ-induced psoriasis-like eruptions, which were resolved by shortening the dose interval. Eruption recurrence was not observed after frequent TCZ subcutaneous injection. Our case may help physicians manage TCZ-induced psoriasis-like eruption.
Keywords: Adverse drug reaction; Atopic dermatitis; Interleukin-6 receptors; Psoriasis; Rheumatoid arthritis; Tocilizumab.