Coligranulomatosis

Coligranulomatosis is an infectious disease caused by a coliform bacillus. The image on the left shows the macroscopic lesions typically found in this disease, consisting in confluent granulomas forming large, yellowish nodules sharply demarcated from the normal parenchyma. Similarly to avian tuberculosis, microscopic lesions consist in nodules of epithelioid and giant cells surrounding a necrotic centre. Acid-fast Ziehl-Neelsen Stain Reaction stains acid-fast Mycobacterium bacilli red, allowing distinction between coligranulomatosis and tuberculosis in dubious cases. PAS staining allows identification of fungal hyphae. Both stains produced negative results (PAS, 400x)..