PMC5577081_01
Chest radiography on initial admission. Reticular patterns were observed in both lower lung fields, along with bilateral hilar adenopathy, and right atrial enlargement.
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Chest radiography on admission (Fig. 1) showed a reticular pattern in both lower lung fields, bilateral hilar adenopathy, and right atrial enlargement.
a: Chest CT on initial admission (lung fields). Ground glass opacities with lobular septal thickening were predominant in both lower lobes. b: Chest CT on initial admission (mediastinum). Mediastinal lymphadenopathy was observed. c: Chest CT on initial admission (mediastinum). Pulmonary artery enlargement was observed.
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Chest computed tomography (CT) on admission (Fig. 2) showed bilateral hilar and mediastinal lymphadenopathy, ground glass opacities with lobular septal thickening, predominantly in both lower lung fields, and pulmonary artery enlargement.
Histopathology at TBLB (EVG staining x100). Fibrous obliteration of the small veins and venules was observed.
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Although alveolar septal fibrosis and the fibrous obliteration of the small veins and venules were present (Fig. 3), these changes were slight and could not lead to the correct diagnosis.
Chest radiography on readmission. Right atrial enlargement and right pleural effusion were observed in addition to a reticular pattern in both lower lung fields and bilateral hilar lymphadenopathy.
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In addition to a reticular pattern in both lower lung fields and bilateral hilar lymphadenopathy, chest radiography also showed right atrial enlargement and a right pleural effusion (Fig. 4).
a: Chest CT on readmission (lung fields). An increase in the reticular granular pattern was observed, predominantly in both lower lobes, along with increased pulmonary vascular markings. b: Chest CT on readmission (mediastinum). Further enlargement of the mediastinal lymph nodes was observed.
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Chest CT revealed an increase in bilateral hilar and mediastinal lymphadenopathy, a small amount of right pleural effusion, a severely enlarged pulmonary artery, increased pulmonary vascular markings, and a reticular granular pattern, predominantly in the lower lung fields (Fig. 5).
a: An echocardiographic image on day 19 of the second hospitalization. b: An echocardiographic image on day 41 of the second hospitalization.
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In addition, her brain natriuretic peptide (BNP) was elevated to 827 pg/mL, pleural effusion developed, and echocardiography showed an increase in TRPG to 62.1 mmHg (Fig. 6a). However, the patient developed severe lower leg edema, and echocardiography on hospital Day 42 showed a further increase in TRPG to 72.9 mmHg (Fig. 6b).
A diagram of the clinical course of the present case.
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Nevertheless, the respiratory insufficiency progressed, and the patient died suddenly on hospital Day 59 (Diagram: Fig. 7).
a: The histopathology at autopsy (EVG staining x40). Hyaline fibrosis of the alveolar septum and fibrous obliteration of the small veins and venules were observed. b: The histopathology at autopsy (EVG staining x100). Fibrous obliteration and narrowing due to concentric intimal thickening of the small veins and venules were observed. c: Histopathology at autopsy (EVG staining x100). The histopathological examination revealed Heath-Edwards grade II and medial hypertrophy of the pulmonary artery without plexiform lesions. d: The histopathology at autopsy [Hematoxylin and Eosin (H&E) staining x40]. Dilated, multi-layered capillaries, hemorrhages in the alveolar spaces and alveolar septum, and areas of hemosiderosis were observed. e: The histopathology at autopsy (H&E staining x40). Enlarged mediastinal lymph nodes with enlarged lymph sinuses and histiocytic hemophagocytosis were observed.
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A histopathological examination showed hyaline fibrosis of the alveolar septa and fibrous obliteration and concentric intimal thickening of the venules (Fig. 8a and b). Heath-Edwards grade II medial hypertrophy of the pulmonary artery was present, but plexiform lesions were not observed (Fig. 8c). There were also dilated, multi-layered capillaries, hemorrhages in the alveolar spaces and alveolar septum, and areas of hemosiderosis (Fig. 8d). The mediastinal lymph nodes were enlarged to 40 mm x 35 mm x 15 mm, with enlarged lymph sinuses and histiocytic hemophagocytosis (Fig. 8e).