Chest computed tomographic findings in rapidly progressive glomerulonephritis

Backgrounds: In patient with rapidly progressive glomerulonephritis (RPGN), coexisting pulmonary lesions are considered to be an adverse prognostic factor. However, there has been no report that examined the frequency of coexisting pulmonary lesions and chest CT findings in patients with RPGN in detail. Objectives: The aim of this study is to investigate the frequency of pulmonary lesion in patients with RPGN and to evaluate the characteristics of chest CT findings among them. Methods: 43 patients diagnosed as RPGN with renal biopsy were included. Patients’ characteristics were evaluated using medical records about background, definitive diagnosis and prognosis. Chest CT images were evaluated about the frequency of coexisting pulmonary lesion and the characteristics of CT findings. Results: The etiologies of RPGN in the study were ANCA-associated GN (55.8%), idiopathic crescentic GN (9.3%), systemic lupus erythematosus (7.0%), renal amyloidosis (4.8%), Henoch-Schönlein purpura (4.7%), Polyarteritis nodosa (2.3%) and Churg-Strauss syndrome (CSS) (2.3%). Among them, coexisting pulmonary lesion was found in 15 patients (34.9%), and most frequent in patients with ANCA-associated GN. About the characteristics of CT findings, CT pattern of chronic interstitial pneumonia (CIP) was most frequent (27.9%). During the following period, new pulmonary lesion was observed in seven of 15 patients (46.7%) with coexisting pulmonary lesion at diagnosis of RPGN and seven of 28 patients (25.0%) without that. Conclusion: We considered that RPGN patients with pulmonary lesion at the diagnosis must be followed carefully.