대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

IgG4-related lung disease

Radiologic Findings

Figure 1. Chest PA shows diffuse nodular opacities in both lung fields and blunting of the right costophrenic angle.
Figure 2-4. Thin section CT images show diffuse nodules, cavities, and nodular consolidation with bronchocentric and perilymphatic distribution, and subtle interlobular septal thickening in both lung fields. Chest CT with mediastinal setting shows marked thickening of pleura and subpleural interstitium in the right lower thorax.
Figure 5. Abdominal CT with portal phase shows infiltrative low-density mass in the right lobe of the liver.
Figure 6. PET/CT scan reveals hypermetabolic uptake in right lower pleura, hepatic masses, and lung nodules.

The patient underwent percutaneous transthoracic biopsy at the right pleura and right pulmonary nodule, and the pathologic result was chronic inflammation and pleuritis with lymphoplasmacytic infiltration. The liver biopsy was also performed and pathology showed obstructive hepatopathy and acute bile ductulitis with infiltration of plasma cells and histiocytes. Some IgG4 positive cells were detected on both lung and liver biopsy specimens. Serial serum IgG4 study showed a prominent increase up to 798 mg/dL. With the diagnosis of IgG4 sclerosing disease in the multidisciplinary discussion, steroid was administered for a month. Bilateral pulmonary infiltration and pleural thickening showed improvement in follow-up chest CT scan. Serum IgG4 dropped to 177 mg/dL.

Brief Review

IgG4-related disease (IgG4-RD) is a recently recognized systemic disease, characterized by tumefactive lesions with lymphoplasmacytic infiltrates with abundant IgG4-positive plasma cell, storiform fibrosis, and usually elevated serum IgG4 concentrations. The lesions commonly involve multiple organs, including lungs, mediastinum, liver, and pancreas. Four patterns were observed in thoracic IgG4-RD, which include interstitium, mediastinum, airways, and pleura. In addition, it may present as a combination of these findings. Mediastinal and hilar lymphadenopathy is the most common pulmonary pattern. The percentage of pulmonary involvement in IgG4-RD is uncertain. On the basis of the predominant radiologic abnormality, pulmonary IgG4-RD could be categorized into four major subtypes: solid nodular type having a solitary nodular lesion that included a mass; round-shaped ground-glass opacity (GGO) type characterized by multiple round-shaped GGOs; alveolar interstitial type showing honeycombing, bronchiectasis, and diffuse GGO; and bronchovascular type showing thickening of bronchovascular bundles and interlobular septa. Our case mainly involved thorax including lung parenchyma and pleura with bronchovascular type, which mimic lymphoproliferative disease. Although IgG4-RD is often difficult to diagnose initially, this case well demonstrates bronchovascular and interstitial distribution of lymphoplasma infiltration in thin section CT.

Please refer to

Case 1184, Case 1156, Case 1039, Case 1015, Case 907, Case 774, Case 723,

KSTR imaging conference 2018 Summer  Case 13 ,
KSTR Imaging Conference 2016 Spring  Case 9 ,
KSTR Imaging Conference 2014 Summer  Case 5,

References

1. Clinical review of pulmonary manifestations of IgG4-related disease. Campbell SN, Rubio E, Loschner AL.Ann Am Thorac Soc. 2014 Nov;11(9):1466-75.
2. Chiu-Fan Chen, Kuo-An Chu, Yen-Chiang Tseng, Chang-Che Wu, Ruay-Sheng Lai. IgG4-related lung disease presenting as interstitial lung disease with bronchiolitis. Medicine (Baltimore). 2017 Dec; 96(49): e9140.
3. Dai Inoue, Yoh Zen, Hitoshi Abo, Toshifumi Gabata, Hiroshi Demachi, Takeshi Kobayashi, Jyun Yoshikawa, Shiro Miyayama, Masahide Yasui, Yasuni Nakanuma, Osamu Matsui. Immunoglobulin G4–related Lung Disease: CT Findings with Pathologic Correlations. Radiology. 2009 Apr;251(1):260-70.

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