Avian hepatic granuloma. A review

Summary

Hepatic granuloma is a chronic inflammatory disease characterized by a granulomatous reaction with accumulation of macrophages and/or epithelioid cells, which may fuse to form multinucleated giant cells. The hepatic granulomas typically have a surrounding rim of lymphocytes and fibrous tissues. The etiology of some hepatic granulomas in birds is well known. It could be due to viral, bacterial, fungal, protozoal, or helminthic infection. The presence of these pathogens in the liver is usually through systemic infections that might preferentially colonize the liver or be opportunistic invaders. Persistence of these pathogens infecting the liver can lead to granulomatous inflammation with different gross lesions and histopathologic patterns depending on the causative agent. This review describes the etiology, clinical signs, pathological changes, and diagnosis in a wide variety of diseases associated with hepatic granulomas in birds in which the detection of granulomatous inflammation is an aid in the differential diagnosis.

Keywords:

• Avian diseases
• Bird diseases
• Hepatic granuloma
• Liver diseases
• Review

Notes

Corresponding author

Address: Department of Pathobiology, Faculty of Veterinary Medicine, University of Utrecht, P.O. Box 80158, 3508 TD Utrecht, The Netherlands

E‐mail: [email protected]