case_images: PMC10627018_01
case_images: Representative photomicrographs of patient's surgical lung biopsies. (A) At scanning magnification, areas of alveolar filling are readily apparent. (B, C) At higher magnification, alveolar spaces are filled with fresh blood, fibrin, and innumerable pigmented macrophages laden with hemosiderin, diagnostic of acute and ongoing diffuse alveolar hemorrhage, and (C) some areas also show iron encrustation of elastic fibers with an associated histiocytic inflammatory reaction and Schaumann body formation, indicative of alveolar hemosiderosis from prior bouts of hemorrhage. (D) In some areas, focally active capillaritis is present with scattered interstitial neutrophils. Though subtle, vacuolated pneumocytes and scattered foamy macrophages can also be seen. Hematoxylin and eosin (all images); original magnifications 20x, 200x, 200x, and 400x, respectively.
case_images: 10.1177_23247096231207689-fig1.jpg
case_images: PMC10627018_01_10.1177_23247096231207689-fig1.jpg
case_images: fig1-23247096231207689
case_images: C-reactive protein level were not obtained on admission. Computed tomographic (CT) imaging of the chest showed bilateral ground-glass opacities suspicious for diffuse alveolar hemorrhage (DAH) (Figure 1).
case_images: Contrast-enhanced CT images with lung windowing in axial plane through the upper, mid, and lower lungs (A-C) and coronal plane (D) demonstrate a central distribution of airspace disease sparing the peripheral subpleural lung with predominant ground-glass opacities in a centrilobular and peri-bronchovascular distribution. There is mild bronchial wall thickening and airway distention in certain regions such as the right middle lobe (B), in addition to areas of developing distortion as evidenced by the linear nature of portions of the airspace disease (arrows, B and C). While the imaging findings are not specific for one disease process, based on imaging alone, differential diagnostic possibilities would include pulmonary hemorrhage, inhalational exposure (such as vaping), infectious bronchiolitis, and organizing pneumonia as a manifestation of acute lung injury. The distortion and mild bronchial dilatation are in keeping with organizing areas of lung injury suggesting some component of subacute or chronic repetitive disease.
case_images: 10.1177_23247096231207689-fig2.jpg
case_images: PMC10627018_01_10.1177_23247096231207689-fig2.jpg
case_images: fig2-23247096231207689
case_images: The pathological examination revealed acute and ongoing DAH, characterized by the combined presence of acute fibrinous lung injury, fresh blood in alveolar spaces, and focally active capillaritis, occurring in a background of alveolar hemosiderosis from one or more prior episodes of DAH in the past, with an accumulation of innumerable hemosiderin-laden macrophages in alveolar spaces and iron encrustation of elastic connective tissue fibers (Figure 2).