대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Immunoglobulin G4 (IgG4)-related lung disease

Radiologic Findings

Fig 1-2. Axial HRCT images show subpleural nodular consolidation with halo appearance in the both lungs, and peripheral mass-like consolidation in the right lower lobe.
Fig 3-6. Even with antibiotic treatment using third-generation cephalosporin, the extent of consolidation of the right lower lobe increased. The consolidation shows internal hypoattenuating area on axial post-contrast CT image. Additionally, ground-glass opacity with septal thickening and small nodules are observed around the consolidation on axial HRCT images.

Brief Review

IgG4-related disease is characterized by diffuse lymphoplasmacytic infiltration, fibrosis, and numerous IgG4-positive plasma cells in affected organs with or without elevated serum IgG4 concentrations. IgG4-related lung disease accounts for about 14% to 54% of patients with IgG4-related disease. IgG4-related lung disease presents a wide spectrum of radiologic features and can be categorized into four major subtypes: solid nodular type, round-shaped GGO type, alveolar interstitial type, and bronchovascular type. Various imaging findings are thought to be a part of a morphological spectrum in the same pathologic process, not a distinct pathologic condition. It is known that most patients respond well to steroid therapy but relapses are common, ranging from 20% to 30% after tapering of glucocorticoid.

References

J Korean Soc Radiol. 2018;79(5):276-281

Keywords