Radiographic solitary pulmonary nodules, 1-5 cm in diameter, or miliary nodules may represent granulomas. They may be found in immunocompromised persons without AIDS, as well as in AIDS patients. It is important to distinguish these granulomas from those caused by mycobacteria or fungi [1].

Figure 1. Miliary Granulomas

This granuloma from a patient with chronic lymphocytic leukemia and diffuse nodules on a radiograph shows apparent central necrosis. At higher magnification, the "necrotic" material appeared foamy, and a GMS stain showed pneumocystis spore cases. Similar granulomas have been described in patients with AIDS [1].

Figure 2. Fibrous Granuloma

A subpleural nodule has an amorphous, fibrous center surrounded by a heavy lymphoid infiltrate.


1. Watts J, Chandler F. Evolving concepts of infection by Pneumocystis carinii. Pathol Annu Part 1, 1991; 26:93-138.

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