PMC5465411_01
Chest CT revealed smooth thickening of the bronchovascular bundle and interlobular septa accompanied by multiple nodules, predominantly in the upper pulmonary lobe (A). Slight enlargement of the mediastinal lymph nodes was also observed (B).
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Chest computed tomography (CT) revealed smooth thickening of the bronchovascular bundle and interlobular septa accompanied by multiple nodules, predominantly in the upper pulmonary lobes (Fig. 1A). The mediastinal lymph nodes were slightly enlarged (Fig. 1B).
Hematoxylin and Eosin staining of the surgical lung specimen revealed histiocyte, lymphocyte, and plasma cell infiltration along the lymphatic structures together with fibrosis.
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A histological analysis showed histiocyte, lymphocyte, and plasma cell infiltration along the lymphatic structures and fibrosis (Fig. 2).
A shows that the stromal lymphatic vessels were dilated (surrounded by arrows) and filled with histiocytes. B shows a high-power field of histiocytes, which displayed a slightly eosinophilic cytoplasm and emperipolesis (arrow).
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Immunohistochemical staining demonstrated that the histiocytes were positive for S100, but negative for CAM5.2, CD1a, and BRAF V600E (Fig. 3, 4).
A and B show D2-staining and S100 staining, respectively. D2-40 is a marker of lymphatic vessel endothelial cells. A shows dilated lymphatic vessels, and B shows lymphatic vessels filled with S100-positive histiocytes.
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Immunohistochemical staining demonstrated that the histiocytes were positive for S100, but negative for CAM5.2, CD1a, and BRAF V600E (Fig. 3, 4).
IgG4 staining of the surgical lung specimen shows infiltrative plasma cells in the surgical lung specimen, which were strongly positive for IgG4. These cells were located in the interlobular connective tissue and thickened alveolar septum (A, B). Obliterative phlebitis was also observed (C).
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The infiltrative plasma cells that were detected in the interlobular connective tissue and thickened alveolar septum were strongly positive for IgG4 (IgG4/IgG ratio: 40%), and obliterative phlebitis was also observed (Fig. 5).
CT showed the swelling of the bilateral submandibular glands (A) and a soft tissue density in the lateral regions of both orbits (B). A chest CT scan obtained at the same time also showed the worsening of lung infiltration (C).
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This was accompanied by a worsening of her lung infiltration (Fig. 6).
IgG4 staining of the submandibular biopsy specimen shows infiltrative plasma cells that were strongly positive for IgG4.
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A submandibular gland biopsy sample revealed marked IgG4-positive plasma cell infiltration with IgG4/IgG ratios of 70% accompanied by fibrosis with a storiform pattern, which was indicative of IgG4-RD alone (Fig. 7).