Fig. 2

a Sagittal section of heavily infected liver; the cysts are round to oval in shape and likely occupy the whole hepatic surface (hematoxylin & eosin). b Three different granulomatous reactions are apparent. The granuloma on the right (arrowhead) lacks an evident collagenous encapsulation, which is present in the other two granulomas (arrow and curved arrow). The presence of necrotic material exfoliating form the inner layer is clearly appreciable in the granuloma in the middle of the figure (curved arrow) (Masson’s Trichrome). c Inside the cyst the nematode (arrows) is immersed in an Alcian Blue positive fluid (asterisk) (Alcian Blue-PAS). d Stratification of granuloma is visible, inner layer formed by epithelioid cells (arrows), middle layer is constituted by mast cells (curved arrows), outer layer with connective fibres (arrowheads) and elongated fibroblasts (Masson’s Trichrome). e Infected liver; intense degranulation of the mast cells (arrows) and macrophage aggregates (arrowheads) are evident (Masson’s Trichrome). f Sagittal section of the infected liver; numerous macrophage aggregates are evident (arrows) (Giemsa). g Sinusoids dilation (arrowheads) and liver hydropic degeneration are appreciable, brownish pigments are visible inside the liver cells (arrows) (Giemsa). Scale-bars: a, 500 μm; b, f, 200 μm; c, 50 μm; d, e, 10 μm; g, 10 μm