Acta Dermato-Venereologica 99-12CompleteContent | Page 28

1174 SHORT COMMUNICATION Pleural Fluid Eosinophilia: A Possible Adverse Event of Interleukin-17 Inhibition Wakiko HAYASHI 1 , Shin-Ichi OSADA 1 *, Aya TOYOSHIMA 1 , Katsuhiro YAMADA 1 , Kazuhisa SUDO 2 , Katsutoshi NAKAYAMA 2 and Motomu MANABE 1 Department of Dermatology & Plastic Surgery, and 2 Department of Respiratory Medicine, Akita University Graduate School of Medicine, Hondo 1-1-1, Akita 010-8543, Japan. *E-mail: [email protected] 1 Accepted Sep 10, 2019; E-published Sep 10, 2019 Brodalumab, a human monoclonal anti-interleukin (IL)- 17 receptor A antibody, is used to treat patients with moderate-to-severe plaque psoriasis in the USA and Europe. In Japan it is also indicated for use in treatment of pustular psoriasis and psoriatic erythroderma (1). Common side-effects of brodalumab include headache, arthralgia, myalgia, fatigue, diarrhoea, superficial fungal infections, and neutropaenia. We report here a case of pustular psoriasis complicated with pleural fluid eosi- nophilia (PFE) following the consecutive administration of brodalumab. CASE REPORT A man in his 40s presented in the emergency department with a 2-day history of left-side chest pain. He had a history of pustular psoriasis for more than 30 years and had been treated with topical glucocorticoids, oral im- munosuppressive agents, and infliximab for the last 7 years. Although his psoriatic lesions were stable with infliximab, because of the inconvenience of intravenous injections every 4 weeks his treatment was switched from infliximab to brodalumab. Psoriasis Area and Severity Index 100 was achieved after 2 injections of brodalumab. The patient received brodalumab 16 times before the development of respiratory symptoms. X-ray and computed tomography (CT) of the chest revealed a pleural effusion in the left lower lung field, leading to a diagnosis of pleuritis. The patient returned home after being prescribed an antibiotic. Four days later he was admitted to respiratory medi- cine because of deterioration of respiratory symptoms and an increased pleural effusion on X-ray (Fig. 1A) and CT (Fig. 1B). Laboratory findings revealed leukocytosis (9,200 cells/l; reference range: 3,300–8,600 cells/l) with eosinophilia (12%; reference range: 2–6.8%) and an elevated C-reactive protein level (10.17 mg/l; reference range: < 0.14 mg/l). Image findings and negative test results for blood and sputum cultures, interferon-γ re- lease assay, autoantibodies, tumour markers, antibodies for mycoplasma, Aspergillus, and Cryptococcus ruled out interstitial pneumonia, bacterial and fungal infec- tions, lung cancer, tuberculosis, and collagen diseases. Cytopathological examination of the pleural effusion revealed massive infiltration of eosinophils (Fig. 1C). A diagnosis of PFE was made and chest drainage was performed, resulting in improvement in the patient’s clinical symptoms and laboratory findings. Because the interruption of brodalumab exacerbated the patient’s psoriatic skin lesions, secukinumab, a human mono- clonal antibody to IL-17A, was introduced. However, pleural effusion in the left lower lung field appeared again after the 5 th administration of secukinumab. Re- sumption of infliximab resolved his skin lesions and respiratory symptoms. DISCUSSION PFE is defined as pleural fluid with a nucleated cell count containing more than 10% eosinophils (2, 3). In a meta- analysis of 687 cases of PFE, the most common causes were malignancy (26%) followed by idiopathic (25%) and parapneumonic (13%) (4). Drug-induced PFE is not so common and approximately 25 drugs have been implicated in the development of PFE, and concomi- tant peripheral blood eosinophilia is sometimes present Fig. 1. (A) X-ray and (B) computed tomography (CT) images of the patient on admission revealed pleural effusion in the left lower lung field. (C) Cytopathological examination of the pleural effusion demonstrated massive infiltration of eosinophils (Giemsa stain; ×1,000). Arrows in (A) and (B) indicate pleural effusion. doi: 10.2340/00015555-3311 Acta Derm Venereol 2019; 99: 1174–1175 This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica.