IPLab:Lab 3:Tuberculosis

Images

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  This is a gross photograph of a lung containing a nodular lesion at the lung apex (arrows). Note that the lesion appears solid and has a whitish coloration indicating considerable fibrous connective tissue. This is a healed granuloma due to primary tuberculosis in the lung. There are smaller focal lesions adjacent to the major mass. In addition, note the extensive anthracosis in this lung.

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  This low-power photomicrograph of a section of lung reveals multiple large nodules (1) with pale eosinophilic centers surrounded by a rim of blue-staining nuclei. In addition to the large nodules, there are several smaller nodules throughout the slide (2).

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  This is a photomicrograph of a tuberculosis granuloma. Note the central core of caseation necrosis (1) encircled by a rim of epithelioid macrophages and lymphocytes (2). Langhans’ type multinucleated giant cells are also present although they are difficult to see at this power (3).

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  This is a high-power photomicrograph of a granuloma. Note the necrotic core on the right (1), epithelioid macrophages (2), and Langhans’ type giant cells (3) at the periphery of the granuloma. Note also the small lymphocytes characterized by their distinctly blue-staining nuclei. Other cells in the tissue, in addition to the macrophages, include fibroblasts and occasional neutrophils.

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  This high-power photomicrograph of a tuberculosis granuloma demonstrates acid-fast bacilli (arrows).