Clinical and Imaging Pulmonary Manifestations in IgG4-Related Disease

ObjectivesThe aims of this study were to describe the frequency of pleuropulmonary computed tomography (CT) findings in patients with IgG4-related disease (IgG4-RD) and to compare clinical and laboratory characteristics between patients with and without pleuropulmonary involvement in chest CT.MethodsThis is a study conducted within the IgG4-RD study group of the Argentine Society of Rheumatology (GESAR IgG4) cohort of patients with IgG4-RD. Member centers of the group were requested to submit pulmonary CT scans of the patients. Lung lesions were classified into 4 subtypes: (1) nodules, (2) ground-glass opacity, (3) interstitial-alveolar involvement, and (4) bronchovascular involvement. The presence of pleural involvement and mediastinal adenopathy was also assessed.ResultsWe examined data from 28 patients, with 17 (61%) showing pulmonary involvement. The subtypes of pulmonary involvement, in order of frequency, were as follows: type 4 (n = 17, 100%), type 3 (n = 10, 59%), type 2 (n = 6, 36%), and type 1 (n = 5, 29%). Pleural lesions were observed in 2 (12%) cases, and mediastinal adenopathies were found in 4 (23%) cases. No demographic, clinical, or laboratory differences were noted between patients with and without pulmonary involvement, except for serum levels of IgG4, which were higher among patients without pulmonary involvement (339.0 [293.1-1592.1 mg/dL] vs 2869 [1156.3-4037.4 mg/dL]; p = 0.022).ConclusionsIn this case series, the predominant subtype of pulmonary involvement was septal thickening and increased bronchovascular tissue. Patients with and without pleuropulmonary involvement exhibited similar clinical and laboratory manifestations, except for serum IgG4, which was higher in patients without pleuropulmonary involvement.