Defining the clinical features of large vessel vasculitiS (LVV) is not easy because their boundaries are not completely clear, their symptoms are very often unspecific, and the correlation between clinical features and imaging, the gold standard of diagnosis, is unpredictable. LVV include giant cell arteritis (GCA), Takayasu's arteritis (TA), isolated ascending aortitis, PMR-associated LVV, retroperitoneal fibrosis, periaortitis, inflammatory abdominal aneurisms, relapsing polychondritis, and IgG4-related diseases.
The organs/tissues affected are various, as in most vasculitides, resulting in symptoms and signs localized to the joints, muscles, eye, brain, kidney, skin and lungs. An interplay between autoimmune and atherosclerosis-associated inflammation is probably at work. Systemic symptoms, including fever, weight loss, malaise, fatigue, night sweats, and depression are often present and may represent the only signs of the disease. At clinical examination, bruits may be present on auscultation. Acute phase reactants are generally unreliable especially for follow-up. Diagnosis relies on imaging, including CE-CT, CE-MRI, and PET/CT or PET/MRI. Vessel biopsy is fundamental to confirm the diagnosis although rarely performed in non-temporal arteritis LVV. Although it is commonly believed that GCA and TA cannot be distinguished by histology, adventitia is relatively spared in TA and commonly damaged in GCA. As in most other rheumatic conditions, the clinician should consider disease activity and damage, although in this case the two entities are not easy to separate. There are no outcome measures specifically developed for LVV, although disease activity has been measured by BVAS, ITAS 2010, and DEI-Tak, each showing some weakness. Damage consists mainly in stenotic or aneurismatic lesions of the vessels, which can appear also long intervals after inflammation has subsided. For this reason, follow-up of patients should continue long-term even if the disease has been apparently cured.
LVV are highly detrimental to the patients, who cannot understand the origin of their symptoms, a situation sometimes shared with the attending clinician since the diagnostic delay may be very long. In addition, long periods of asymptomatic disease, with on-going damage, are not rare. Disease-specific patients reported outcomes have not been developed in these conditions, and are a field open to research.
Disclosure of Interest None declared