A 64-year-old man was admitted to our hospital with an abnormal chest shadow. The patient was a current-smoker and had a past illness of autoimmune pancreatitis with a high serum level of IgG4, 348 mg/dL. Chest CT showed upper-lobe emphysema, and lower-lobe reticulation with honeycombing, suggestive of combined pulmonary fibrosis with emphysema (CPFE). Surgical lung biopsy was revealed a usual interstitial pneumonia pattern with marked infiltration of IgG4-positive plasma cells. The patient was diagnosed with IgG4 related disease (IgG4-RD) presenting with CPFE. Pulmonary manifestation was improved by corticosteroid therapy. IgG4-RD may be an underlying condition in patient with CPFE.
Keywords: AIP, autoimmune pancreatitis; CPFE, Combined pulmonary fibrosis with emphysema; CT, computed tomography; CTD, connective tissue disease; Combined pulmonary fibrosis and emphysema (CPFE); DIP, desquamative interstitial pneumonia; DLco, diffusion capacity for carbon monoxide; FEV1.0, forced vital capacity in 1 second; FVC, forced vital capacity; GGO, ground-glass opacities; HE, hematoxylin-eosin; HRCT, high-resolution CT; IIP, idiopathic interstitial pneumonia; IL, interleukin; ILD, interstitial lung disease; IPF, idiopathic pulmonary fibrosis; IgG4-RD, IgG4-related disease; IgG4-RLD, IgG4-related lung diseases; IgG4-related disease (IgG4-RD); NSIP, nonspecific interstitial pneumonia; PFT, pulmonary function tests; RA, rheumatoid arthritis; TGF, tissue growth factor; UIP, usual interstitial pneumonia; Usual interstitial pneumonia (UIP).