• Lung Disease: CT Findings with Pathologic Correlations

    Radiology: Volume 251: Number 1—April 2009

    Dai Inoue, MD Yoh Zen, MD Hitoshi Abo, MD Toshifumi Gabata, MD Hiroshi Demachi, MD Takeshi Kobayashi, MD Jyun Yoshikawa, MD ShiroMiyayama, MD Masahide Yasui, MD Yasuni Nakanuma, MD Osamu Matsu, MD

    Purpose: To retrospectively analyze radiologic findings of immuno­globulin G4 (lgG4)-related lung disease as correlated with pathologic specimens

    Materials and Methods:This study was approved by the institutional review board, and all patients had consented to the use of their medical records for the purpose of research, This study included 13 patients with IgG4-related lung disease (nine men and four women; age range, 43-76 years). Computed tomo­graphic (CT) findings were retrospectively analyzed with regard to the characteristics, shape, and distribution of the radiologic findings and were correlated with surgically resected, or biopsy lung specimens in seven patients. Sta­tistical analysis was not used in this study.

    Results:On the basis of the predominant radiologic abnormality, IgG4-related lung disease could be categorized into four major subtypes: solid nodular type having a solitary nodu­lar lesion that included a mass (four patients); round-shaped ground-glass opacity (GGO) type characterized by multiple round-shaped GGOs (two patients); alveolar in­terstitial type showing honeycombing, bronchiectasis, and diffuse GGO (two patients); and bronchovascular type showing thickening of bronchovascular bundles and inter­lobular septa (five patients). Pathologically, solitary nodu­lar lesions consisted of diffuse lymphoplasmacytic infiltra­tion with fibrosis. Thickened bronchovascular bundles or interlobular septa and GGO on CT images pathologically corresponded to lymphoplasmacytic infiltration and fibro­sis in peribronchiolar or interlobular interstitium and alve­olar interstitium, respectively. The radiologic findings of honeycombing corresponded to disrupted alveolar struc­tures and dilated peripleural air spaces.

    Conclusion: IgG4-related lung disease manifested as four major catego­ries of CT features. Pathologically, these features corre­sponded to IgG4-related sclerosing inflammation along the intrapulmonary connective tissue.