ANALYSIS OF THERAPEUTIC STRATEGIES AND DEFINITION OF GOALS FOR THE MANAGEMENT OF ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY (ANCA) ASSOCIATED VASCULITIS

Vasculitis consists in vessel walls inflammation. A subgroup of these pathological entities, Anti-Neutrophil Cytoplasmic Antibody Associated Vasculitis, which predominantly affects small caliber vessels, is characterized by necrotizing features with few or no immune deposits. Thanks to the advances in the therapeutic management, the course of the disease has been transformed from a highly lethal condition to a chronic and relapsing one, with benefit for survival rate. Given the chronicity, both the disease itself as well as the drug related side effects influence the long-term outcome. During the past decades, many different tools have been developed to assess disease activity and damage, also to prevent damage accrual progression and favor a better quality of life. Up to date, despite serious scientific interest, a major consensus about definitions of the disease state is lacking; treatment strategies and targets are still an evolving field. The prevalence of Remission, Low Disease Activity State (LDAS) and long-term damage accrual were investigated during a 5-year follow-up in patients with Granulomatosis with Polyangiitis (GPA), Microscopic Polyangiitis (MPA) and Eosinophilic Granulomatosis with Polyangiitis (EGPA). As it concerns Granulomatosis with Polyangiitis (GPA) and Microscopic Polyangiitis (MPA) patients, the long-term outcome has been shown to be significantly worse, in terms of damage, in patients with a prolonged Low Disease Activity State (LDAS) when compared to patients in Remission state. Interestingly, factors identified as contributors for the failure to achieve a prolonged remission were younger age, Granulomatosis with Polyangiitis diagnosis, Proteinase 3 Anti-Neutrophil Cytoplasmic Antibody, ORL or pulmonary involvement and higher Vasculitis Damage Index (VDI) scores at 2 and 5 years of follow-up. Preliminary data from the cohort of Eosinophilic Granulomatosis with Polyangiitis (EGPA) patients did not report a statistically significant association between the disease activity states and the long-term damage, estimated as Vasculitis Damage Index (VDI) burden. In conclusion, if on the one hand the findings shed light on the need of achieving Complete Remission as therapeutic goal in Granulomatosis with Polyangiitis and Microscopic Polyangiitis patients, on the other hand further investigations are warranted in order to define therapeutic goals in Eosinophilic Granulomatosis with Polyangiitis patients.