Figure 14-46.

Granulomatous Encephalitis, Brain.

A, Dog. This inflammatory response, consisting of a mixture of macrophages, multinucleated giant cells (arrow), lymphocytes, varying numbers of neutrophils, and occasional plasma cells, is typical of central nervous system infections by fungi and algae. Blastomyces dermatitidis microbes are present in the exudate and within macrophages and giant cells (arrowheads). H&E stain. B, Alpaca. Coccidioides immitis–associated encephalitis. Large numbers of neutrophils and macrophages (pyogranulomatous inflammation) surround sporangia of C. immitis (arrows). H&E stain.

(A courtesy Dr. J.F. Zachary, College of Veterinary Medicine, University of Illinois. B courtesy Dr. A.D. Miller, College of Veterinary Medicine, Cornell University.)