ABSTRACT
ANCA-associated vasculitides (AAV) are multisystem autoimmune diseases characterised by necrotizing inflammation of small blood vessels, production of antibodies against antigens found in the cytoplasm of neutrophils (ANCA) and various organ manifestations. The aim of the present study was to analyse the type and frequency of symptoms of respiratory tract involvement in AAV. A total of 145 patients with AAV were included in the study, of which 80 had granulomatosis with polyangiitis (GPA), 52 with microscopic polyangiitis (MPA), 8 with Churg-Strauss syndrome (CSS) and 5 with undifferentiated vasculitis. Of all patients with AAV, respiratory tract involvement was observed in 118. Symptoms of involvement of the upper airways were significantly more common in GPA compared to MPA and CSS (p = 0.0000). The most common manifestation was rhinorrhoea, which had blood stains in 78.6% of patients. Involvement of the paranasal sinuses was reported in 47 patients, mainly those with GPA (71.4%). A total of 110 patients, or 75.9%, had symptoms of pulmonary involvement, which makes the lung the most commonly targeted organ in Bulgarian patients with AAV. Pulmonary manifestations were most common in patients with GPA (65.6%), followed by MPA (24.5%) and CSS (7.3%);all differences were reported to be statistically significant (p = 0.0000). The most frequently observed symptom in our patients was cough - in 83 individuals, and in 57 patients (68.57%) it was accompanied by blood-stained sputum. Alveolar haemorrhage was observed significantly more often in cases of MPA (p = 0.0266), the same being true of respiratory failure (p = 0.0257). The conducted computed tomography (CT) scans showed predominantly nodules (in 54.5% of cases with pulmonary involvement), and 19.1% of them evolved to cavitations. Nodules were a significantly more common finding in patients with GPA - in 68.1% of cases (p = 0.0000). The typical findings of vasculitis - alveolar damage and 'ground glass' opacities were found significantly more often in MPA (p = 0.0150). Pulmonary fibrosis was observed in both GPA and MPA.