ORIGINAL ARTICLE The value of ultrasound in diagnosing extracranial large-vessel vasculitis compared to FDG-PET/CT: A retrospective study Christian Löffler 1 & Johannes Hoffend 2 & Urs Benck 1 & Bernhard K. Krämer 1 & Raoul Bergner 3 Received: 11 March 2017 /Revised: 23 April 2017 /Accepted: 26 April 2017 # International League of Associations for Rheumatology (ILAR) 2017 Abstract Large-vessel vasculitis (LVV) is a group of dis- eases mainly comprised of giant-cell arteritis (GCA), Takayasu arteritis, and a series of rare diseases like Behçet’ s disease, IgG4-related disease, infectious aortitis, and other unfrequent entities. Besides clinical and labora- tory features, Doppler sonography (DS) can assist in estab- lishing the diagnosis. Its diagnostic sensitivity has been evaluated in various studies, most of them, however, in temporal arteritis (TA) respectively in LVV with involve- ment of the temporal artery. Little is known in extracranial LVV. We retrospectively evaluated the diagnostic accuracy of DS in 30 patients with extracranial, non-temporal LVV using the highly sensitive PET/CT as method of reference in comparison to 20 controls who were found to have no LVV. We investigated ten arterial sites and documented the presence of the sonographic halo sign. Sensitivities of DS for LVV were highest in the subclavian and axillary arter- ies (71.4%/72.2%) and low in the abdominal aorta (26.1%) and the common femoral artery (16.7%). DS detected 24 out of 30 cases of LVV (overall sensitivity 80.0%). The LVV cases where DS was completely negative did not significantly differ in leukocyte count, C-reactive protein, or erythrocyte sedimentation rate from LVV cases with positive DS. DS is a potent method in diagnosing extracra- nial LVV especially in the axillary and the subclavian ar- teries. Aortic, intraabdominal, and lower extremity artery manifestations, however, are often missed by DS. A sec- ond imaging modality (e.g., PET/CT) is therefore required. Keywords Giant-cell arteritis . PET/CT . Ultrasonography . Vasculitis Introduction The diagnosis of large-vessel vasculitis (LVV) can be chal- lenging since clinical signs and symptoms are heteroge- neous and might be misleading. Giant-cell arteritis (GCA) with or without temporal arteritis (TA) is by far the most prominent representative of LVV [1]. Takayasu arteritis and Behçet’s disease are less common [2], and entities such as IgG4-related aortitis [3], infectious aortitis (e.g., in syphilis), and Cogan’ s syndrome [4] are consid- ered to be rare causes of LVV. The leading clinical features are myalgiform limb pain, fever, weight loss, and night sweats. Laboratory studies are characterized by increased C-reactive protein (CRP) levels and an elevated erythro- cyte sedimentation rate (ESR). Color Doppler sonography (DS) is capable of detecting vascular inflammation displayed as hypoechoic wall thickening reflecting vessel wall edema (also known as halo sign [5]), stenosis, or complete vessel occlusion. Its sensitivity in TA ranges be- tween 10 and 100% [6–9], and in extracranial LVV, it is reported to be between 55 and 100% [10–12]. The standard of reference in most of these studies was either the American College of Rheumatology (ACR) criteria from 1990 and/or a temporal artery biopsy (TAB). * Christian Löffler christian.loeffler@umm.de 1 Department of Nephrology, Hypertensiology, Rheumatology, University Hospital Mannheim, University of Heidelberg, Germany, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany 2 Department of Diagnostic and Interventional Radiology, Klinikum Ludwigshafen, Bremserstr. 79, D-67065 Ludwigshafen, Germany 3 Department of Rheumatology, Nephrology, Oncology, Klinikum Ludwigshafen, Bremserstr. 79, D-67065 Ludwigshafen, Germany Clin Rheumatol DOI 10.1007/s10067-017-3669-7