IgG4-related disease presenting with combined pulmonary fibrosis and emphysema (CPFE)

Abstract

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).

Fig. 1

Chest computed tomography (CT) shows emphysema in bilateral upper lobes (A) and reticulation with honeycombing in bilateral lower lobes (B), suggestive of combined pulmonary fibrosis with emphysema (CPFE). In addition, high-resolution CT (HRCT) reveals the extent of ground-glass opacities (GGO) around emphysema and fibrotic lesion, multiple nodules, and thickening of bronchovascular bundles (C).

Fig. 2

Histopathological findings of video-assisted thoracoscopic lung biopsy specimen from the right S³ and S⁵. The specimens showed patchy distribution and involvement of the subpleural and paraseptal fibrosis with airspace enlargement and honeycombing (A: × 4, hematoxylin-eosin [HE] stain). There is a dense lymphoplasmacytes infiltration with lymphoid aggregates in the alveolar septa and bronchovascular bundles (B: × 40, HE stain). Plasma cell infiltration is prominent (C: × 200, HE stain), and the immunohistochemical staining with IgG (D: × 200) and IgG4 (E: × 200) shows an IgG4/IgG-positive cell ratio of approximately 65%.

Fig. 3

Chest computed tomography (CT) after 6 months of corticosteroid therapy shows significantly improvement of ground-glass opacities (GGO) and/or consolidation around emphysema and fibrotic change in upper lobes (A) and in lower lobes (B). High-resolution CT (HRCT) reveals that the extent of GGO disappearance, loss of multiple nodules, and the decrease in the thickening of bronchovascular bundles (C).