Morphological patterns of the liver in South American blastomycosis

Histological features were semi-quantitatively analysed in 60 livers, obtained by necropsy, from patients who died of South American blastomycosis. These findings were classified and correlated with duration of the disease and treatment. Bile-duct lesions were prominent and a particular pattern was found in which segments of bile ducts were "disrupted" and replaced by inflammatory reaction. A classification of the lesions is proposed: Class o--near normal livers; Class I--predominance of necrosis and suppuration; Class II--predominance of tuberculoid granulomas; Class III--portal fibrosis and non-specific infiltrate. There has been no evidence that treatment could induce bile-duct proliferation, fatty change of liver cells, or cholestasis. On the other hand, less fibrosis was found in treated patients. Pathogenesis of the bile-duct lesions is discussed.