Anemia and thrombocytosis associated with erythrodermic psoriasis successfully treated with ixekizumab: A case report

Abstract

Introduction: Erythrodermic psoriasis is a rare and potentially life-threatening subtype of psoriasis. It can be accompanied by systemic inflammatory disorders such as arthritic, hematologic, hemodynamic, and metabolic disturbances. We herein report a case involving a woman with erythroderma, joint deformities, anemia, and thrombocytosis who was diagnosed with erythrodermic psoriasis and psoriasis arthritis that were successfully treated with interleukin-17A antibody. Case presentation: A 35-year-old woman presented with an almost 20-year history of recurrent erythema and desquamation. She was diagnosed with plaque psoriasis and psoriatic arthritis and treated with acitretin, etanercept combined with methotrexate, and etanercept combined with cyclosporin, respectively. However, at the time of consultation, she was experiencing an episode of severe skin and joint inflammation. Routine laboratory evaluation revealed moderate microcytic hypochromic anemia, thrombocytosis, and increased serum cytokine concentrations. The patient was given the standard dose of ixekizumab, which resulted in clearance of her skin lesions with a Psoriasis Area and Severity Index 90 response at week 12. Her arthritic symptoms, including arthralgia and joint dysfunction, also improved. Moreover, her hemoglobin concentration, platelet count, and inflammatory markers reached the normal ranges. Discussion: Multiple cytokines participate in the pathogenesis of erythrodermic psoriasis, including interleukin-17A, interleukin-6, interleukin-1β, and interleukin-8. In the present case, treatment targeting the interleukin-23/interleukin-17 axis showed great efficacy not only for the skin lesions but also for systemic inflammatory comorbidities, such as arthritis, anemia, and thrombocytosis. Conclusion: Patients with systemic inflammatory disorders related to psoriasis, such as anemia and thrombocytosis, may benefit from anti-IL-17A treatment.