TY - JOUR T1 - An Adult Fatal Case with a <em>STAT1</em> Gain-of-function Mutation Associated with Multiple Autoimmune Diseases JF - The Journal of Rheumatology JO - J Rheumatol SP - 325 LP - 327 DO - 10.3899/jrheum.180210 VL - 46 IS - 3 AU - KEISUKE MAESHIMA AU - KOJI ISHII AU - HIROTAKA SHIBATA Y1 - 2019/03/01 UR - http://www.jrheum.org/content/46/3/325.abstract N2 - Primary immunodeficiency diseases (PID) are a heterogeneous group of diseases with variable genetic etiologies. Although immunodeficiency is a hallmark of susceptibility to infection, autoimmunity is clearly a prevalent feature1. Some PID, including common variable immunodeficiency (CVID), are often adult-onset conditions2. Heterozygous gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) gene have been identified as underlying causes of chronic mucocutaneous candidiasis, a childhood-onset PID3; however, its comprehensive clinical features and outcomes remain undefined. We present a patient with a STAT1 GOF mutation associated with multiple autoimmune diseases, including Takayasu arteritis (TA), a previously unreported phenotype of STAT1 GOF mutations.We obtained ethics approval for our study from the ethical committee of the Faculty of Medicine, Oita University, Japan (ethics approval number: 1387). Written informed consent was obtained from the patient’s family to publish the material.The patient was a 25-year-old Japanese woman diagnosed at 8 years of age with autoimmune hypothyroidism and treated with hormonal substitution therapy. She lacked a familial history of associated PID and remained symptom-free throughout childhood and adolescence under hormonal therapy. At 21 years, TA was accidentally diagnosed because of a pulseless right radial artery, with no other symptoms. TA-associated HLA-B674 was positive. Damaged large vessels from neck to lower … Address correspondence to K. Maeshima, Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu, Oita, 879-5593, Japan. E-mail: maeshima{at}oita-u.ac.jp ER -