Ear, nose and throat involvement in granulomatosis with polyangiitis: how it presents and how it determines disease severity and long-term outcomes.

Ear, nose and throat (ENT) manifestations in granulomatosis with polyangiitis (GPA) represent the most frequent symptoms at disease onset. The aim of the study was to analyse ENT involvement at diagnosis, as well as how it could influence relapse rate, mortality and disease severity. A retrospective non-controlled cohort study was performed including all consecutive diagnosed GPA from 1996 to 2016 in two rheumatology centres of Northern Italy, focusing particularly on ENT presenting signs and symptoms at baseline. Eighty-nine patients (48.3% females) with new onset GPA were evaluated. They were mostly Caucasian (97.7%), middle aged (mean 54.5 years) and more frequently anti-neutrophil cytoplasmic antibodies (ANCA) positive (78.6%) with PR3 specificity (81.4%). At diagnosis, ENT involvement was reported in 71.9% patients, second only to systemic symptoms. These patients were significantly younger at disease onset (0.013), with less frequent renal involvement (0.014) irrespectively to ANCA status, but with significantly higher Vasculitis Damage Index (VDI) (0.001). The most frequent ENT manifestation was sinonasal involvement (58.4%, 73% of which with nasal inflammation/chronic sinusitis and 48% with nasal crusting), while otologic involvement (mainly otitis media/otomastoiditis) was observed in 34.8%. ENT-GPA patients presented a higher survival rate at 5 years (98.1 vs 77.7%, 0.049), and ENT involvement resulted to be an independent predictor of better outcome (OR 0.37, 95% CI 0.2-0.8, 0.019). Our data confirms that ENT involvement is not only one of the key clinical features of GPA, but also could point out a milder GPA subset with lower renal involvement and lower mortality rate, irrespectively to ANCA status.