Inflammation and Repair 1 Outline (part-4) In Pathologic Basis Of Disease

21 - Lymph node, sarcoidosis - Very low power (Glass slide 65)

The multiple small pink nodules that interpose themselves diffusely within the normal architecture of the lymph node are the granulomas.

22 - Lymph node, sarcoidosis - Medium power (Glass slide 65)

•  Giant cells

The granulomas are closely packed, often merging, with scant intervening lymphoid tissue. Scattered multinucleated giant cells are apparent.

23 - Lymph node, sarcoidosis - High power (Glass slide 65)

• Foreign body-type giant cell
• Langhans-type giant cell

This is a noncaseating granuloma, composed of epithelioid (activated) macrophages. A foreign body-type giant cell with dispersed nuclei and a Langhans-type giant cell with peripheral nuclei are seen. These are formed of fused macrophages.

24 - Lung, granulomatous inflammation, miliary tuberculosis - Gross, cut surface

Miliary TB is a disseminated TB infection. Innumerable tiny whitish nodules (granulomas) are visible.

25 - Spleen, granulomatous inflammation, miliary tuberculosis - Gross, cut surface

As seen in the previous image of the lung, this spleen contains numerous small foci of granulomatous inflammation. Note that this has a similar appearance to the spleen with sarcoidosis, shown in a previous image.

26 - Liver, miliary tuberculosis - Low power (Glass slide 52)

• Granulomas
• Normal liver

Two granulomas are apparent. Note that they have focally replaced the normal liver tissue.

27 - Liver, miliary tuberculosis - Medium power (Glass slide 52)

• Giant cell

A higher power view demonstrates that the granuloma is composed of epithelioid macrophages and multinucleated giant cells. Lymphocytes are also scattered through the granuloma. Note that the early granulomas in miliary TB may not yet have developed caseous necrosis.

28 - Liver, miliary tuberculosis with a focus of caseous necrosis - High power (Glass slide 52)

• Caseous necrosis

The center of this granuloma is pink with no visible cellular architecture - the characteristic appearance of caseous necrosis. Though granulomatous inflammation has a number of causes, caseous necrosis virtually always signifies an infectious process.

29 - Arm, healing surgical incision - Clinical presentation

This image demonstrates healing by first intention, which occurs in clean, uninfected wounds that have apposed edges.

30 - Skin, healing surgical incision - Very low power (Glass slide 18)

• Dermis
• New epithelium
• Locus of prior incision

This image is for orientation.