006. LARGE VESSEL INVOLVEMENT IN ANTI_NEUTROPHIL CYTOPLASMIC ANTIBODY–POSITIVE VASCULITIS

Abstract

Background: We herein present two cases that demonstrate large vessel (LV) involvement in the context of ANCA-associated vasculitis (AAV). Are these two separate co-existing entities or a spectrum of the same disease? Methods: The first case, a 66 year old male diagnosed with classic features of Granulomatosis with polyangiitis (GPA) with pulmonary nodules, renal involvement and a PR3 >177. He responded well to corticosteroids, iv Cyclophosphamide and maintenance Azathioprine. He re-presented 4 months later with severe abdominal pain warranting a CT of the abdomen which demonstrated thickening of the aorta and innominate arteries. PET/CT confirmed the findings. He was placed on Rituximab and is now in remission. The second case is that of a 66 year old male who presented with jaw and tongue claudication, limb ischaemia, fleeting arthralgia and constitutional symptoms. CRP was 15, PR3 72. Giant cell arteritis (GCA) with large vessel involvement was suspected. Temporal artery biopsy gave the appearance typical of healing GCA. He was treated with IV corticosteroids and Azathioprine with good response. On weaning Corticosteroids, limb claudication symptoms ensued. IV Cyclophosphamide was administered along with weaning dose steroids. Several months later lung cavities were noted on CT scan which was performed for chest symptoms. Histology demonstrated necrotizing granulomas consistent with GPA and an aspergilloma within the cavity. Bronchial washing cultivated Aspergillus spp. He was treated with antifungals, antibiotics and later Rituximab. Despite remission, he continued to have respiratory symptoms related to lung cavitation. Results: Although very rare, large vessel involvement associated with GPA has been documented in case reports. Large vessel involvement can precede the development of or occur in the absence of small vessel vasculitis. It usually presents in the form of periaortitis, aortitis or Temporal arteritis. LV involvement in AAV often has a poor outcome with aortic dissection, rupture and stenosing arteries. This usually occurs in both MPO and PR3 subtypes. The epidemiologic, clinical and histological characteristics of these patients differ from those of the well-defined large vessel vasculitides such as GCA or Takayasu's arteritis. Biopsy is indicated to establish diagnosis. Small temporal artery branches and vasa vasorum involvement in GCA are common, however, frank finbrinoid necrosis is unusual in classical GCA and could be suggestive of systemic necrotizing vasculitis. Involvement of the posterior ciliary arteries, which are small branches of the ophthalmic artery resulting in anterior ischaemic optic neuropathy (AION) can occur in both. Conclusion: It is important to recognize that large vessel inflammation occurs in ANCA-associated vasculitides and is part of a spectrum of disease. It can precede or follow the classical manifestations of ANCA positive vasculitis and it seems to respond as well to B cell depletion.