liver diseases. Special stains for microorganisms should be performed, as epithelioid granulomas can be associated with infectious organisms.
Table 11.1 Causes of hepatic granulomas
Figure 11.6 Fibrin-ring granuloma. Epithelioid granulomas with a central lipid droplet surrounded by an eosinophilic fibrin ring.
oil and may be stained with Oil red O on frozen sections (Fig. 11.9). Lipogranulomas often have a bit of associated fibrosis, but overall do not contribute to liver fibrosis. They are commonly associated with fatty liver disease or chronic hepatitis C but can also be incidental findings. They are usually found within the portal areas or next to the central veins.
Figure 11.8 Foreign body granuloma, polarized light. Same case as in Figure 11.6, highlighting the titanium granules under polarized light.
as Whipple’s disease and Rhodococcus equi may also cause foamy histiocytic aggregates within the liver.
Figure 11.10 Mycobacterium avium-intracellulare. Aggregates of foamy histiocytes are found within the lobule.