To integrate the clinical, radiologic and pathologic features of Granulomatosis with Polyangiitis, focusing on lung manifestations.

Granulomatosis with Polyangiitis (GPA), formerly Wegener’s Granulomatosis, is an uncommon disease pathologically characterized by a necrotizing vasculitis associating a granulomatous inflammation peri and extravascular. Although the etiology of the disease remains unknown, an autoimmune cause is considered, which may be triggered by environmental events, due to the presence of circulating antineutrophil cytoplasmic antibodies (ANCA), directed against proteinase 3 (C-ANCA) and much less commonly, against myeloperoxidase (P-ANCA). According to the Chapel Hill Consensus Conference of 2012 on the nomenclature of vasculitis (Fig.1), GPA integrates the group...

Lung involvement Imaging findings Pulmonary nodules and masses Nodules and masses are the most common manifestations of GPA, seen in approximately 70-90% of patients, at presentation or during the course of the disease. They may be single or multiple (usually under 10 lesions) and bilateral, often related to vessels tending to involve the subpleural regions, with no predilection for the upper or lower lung zones. Sizewise they range from a few millimeters to 10 cm (Fig.2 and Fig.3), usually measuring between 2 cm and 4...

The diagnosis of GPA is often delayed because its signs and symptoms often overlap with other more common diseases, like pneumonia and neoplasm. An integrated clinical, serological, radiological and histopathological approach is usually needed. The poor prognosis and the need for prompt therapy emphasize the importance of early diagnosis, and the radiologist may be the first physician to suggest it, based on common imaging findings, including pulmonary nodules and masses, often cavitated, ground-glass opacities and areas of consolidation. Although the reference standard for definite diagnosis...

M. P. V. A. E. Sousa; Lisbon/PT - nothing to disclose G. Matos Ferreira; Lisbon/PT - nothing to disclose

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