A 50-year-old man was admitted to the Department of Rheumatology at Peking Union Medical College Hospital with rash for 6 months, and fever and hematuria for 5 months. The main clinical manifestations included fever, fatigue, purpura, hematuria and thrombocytopenia. He was positive for antinuclear antibody (ANA), anti-neutrophil cytoplasmic antibodies (ANCA) and rheumatoid factor (RF), and had low complement levels. Initial blood culture, echocardiography and chest CT showed no signs of infection. Diagnosis of connective tissue disease was made initially. His disease improved under treatment with glucocorticoids and immunosuppressive agents, but relapsed when glucocorticoids were tapered. After admission, the diagnosis was reconsidered, and infective endocarditis was finally diagnosed with repeated positive blood cultures and vegetations detected by transesophageal echocardiography. Amoxicillin and clavulanate potassium were initiated, and surgery was performed. His symptoms finally recovered gradually.

Takayasu's arteritis (TAK) is a chronic large vessel vasculitis that involves the aorta and its primary branch arteries, which can result in limb ischemia and organ damage. A clinical practice guideline has been newly developed under the leadership of the National Clinical Medical Research Center for Dermatologic and Immunologic Diseases. This guideline provides evidence-based recommendations on 11 key issues in the management of TAK, covering the diagnosis, clinical evaluation, medical treatment, antithrombotic therapy, surgical intervention as well as pregnancy, and aims to guide the diagnosis and treatment of TAK in clinical practice and improve the outcomes of patients in China. This article interprets the key points of this guideline, in order to promote its application.