Pulmonary involvement in antineutrophil cytoplasmic antibody‐associated vasculitides: A single center experience from Turkey

Pulmonary involvement is an important cause of mortality and morbidity in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). In this study, we aimed to evaluate the type and frequency of pulmonary involvement and investigate the potential relationship between thorax computed tomography (CT) signs and other systemic clinical findings in AAV.A total of 63 patients over the age of 18 and diagnosed with AAV were included in this study. Thoracic CT imaging findings and clinical features of the patients at the time of diagnosis were retrospectively evaluated. The frequency and distribution of detected pathological findings on imaging according to disease types, in addition to the relationship of these findings with other systemic findings and disease severity, were analyzed.Of 63 patients, 50 (79.4%) had pulmonary symptoms at the time of presentation. Most frequently observed pulmonary finding of thorax CT was nodular opacity. Consolidation, cavitary nodules, bronchiectasis, emphysema and fibrotic sequelae change were more common in the patients with diagnosis of granulomatosis with polyangiitis. Honeycomb, atelectasis, interstitial pneumonia, pulmonary venous congestion and pleural effusion were more common in the patients with diagnosis of microscopic polyangiitis. Ground-glass appearance, central airway disease, peribronchovascular nodules, pericardial effusion and lymphatic adenomegaly (>10 mm) were more common in the patients with diagnosis of eosinophilic granulomatosis with polyangiitis. Interstitial lung disease, pulmonary hemorrhage and severe lung involvement were found significantly increased in patients with myeloperoxidase antibody (MPO)-ANCA positivity (P < 0.05).Lung involvement was detected in almost all of the patients with AAV. Both interstitial lung disease and severe lung involvement were more frequently found in patients with MPO-ANCA positivity compared to other patients. Pulmonary examination by an imaging technique in all patients with AAV may be useful to determine the vasculitis subtype and to determine the extent of the disease.Pulmonary involvement is quite common in AAV. Every patient with suspected AAV should be examined with imaging for lung involvement, even in the absence of respiratory symptoms. Severe pulmonary involvement is associated with the presence of severe disease and MPO-ANCA positivity.