16286 A case of acute myeloid leukemia during adalimumab treatment in a patient with psoriatic arthritis

Abstract

Adalimumab, a fully human anti–tumor necrosis factor alpha (TNF-α) monoclonal antibody, which has been successfully used in the treatment of several immune-mediated disorders including psoriasis. Hematologic malignancies or lymphoproliferative disorders associated with the use of TNF-α inhibitors in psoriatic patients have been reported. A 62-year-old male patient presented with plaque psoriasis for 20 years’ duration. Although he had received narrowband ultraviolet B phototherapy for 3 years and oral methotrexate for 6 months, none of them were satisfactory. The patient also complained of pain in multiple joints and onycholysis. Psoriatic arthritis was diagnosed based on the Classification criteria for psoriatic arthritis (CASPAR). He started to receive the treatment of subcutaneous injection of adalimumab 40 mg according to the dosing schedule of plaque psoriasis. During loading dose and initial 6 months, psoriatic skin lesion and arthralgia improved gradually. After 16 injections of adalimumab, the patient complained of myalgia, headache, and fatigue. Blood tests showed marked leukocytosis, anemia and low platelet counts, and the blast count was 45%. The patient was diagnosed with acute myeloid leukemia (AML) by additional bone marrow tests. We report this case of AML during the treatment with adalimumab to raise the awareness of the rare possibility of hematologic malignancy.