Histologic changes: At low power, this non-distended biopsy shows patchy alveolar collapse--an artifact of preparation, which could have been prevented by distending the unfixed biopsy with formalin. Two abnormalities are present. Several dark blue, lymphoid aggregates suggest chronic inflammation, and the bronchiole to the left of the large artery has an irregularly-shaped lumen with surrounding fibrosis.
At higher magnification, there are foci of active inflammation with pink fibrinous exudate and scattered fragmenting PMNs (the tiny nuclear specks in the pink exudate) in alveolar spaces (arrows). In addition, the alveolar walls show an alveolitis--widening, lymphocytic infiltrates, and type II cell hyperplasia.
At higher magnification, the small vein is surrounded by a number of eosinophils as well as some PMNs and lymphoid cells. This reaction is non-specific and does not represent a destructive angiitis.
Clinical summary Image 2
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