Diagnostic imaging in sheep hepatic fascioliasis: ultrasound, computer tomography and magnetic resonance findings

Abstract

Radiological features and biochemical changes were investigated during the parenchymal and ductal phases of chronic Fasciola hepatica infection in sheep. The activities of plasma aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and gamma-glutamyl transpeptidase (GGT), plasma levels of IgG anti- F. hepatica and serial ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) findings were studied in eight sheep infected with 150 F. hepatica metacercariae. Experimental fluke infection provoked an increase in plasma level of IgG directed against F. hepatica and in plasma LDH and AST activities from 4 weeks after infection. Enzyme activities did not significantly differ from the baseline after 15 and 12 weeks for LDH and AST, respectively. GGT activity increased from 9 weeks postinfection and still remained significantly elevated at 18 weeks. In the parenchymal phase, both CT and MRI showed nodular lesions in five animals and MRI could also detect early tracks in the subcapsular area in three sheep. Ultrasound findings were nonspecific in this phase. Ductal dilatation was shown by ultrasound, CT and MRI in almost all animals, although MRI was inferior to CT in depicting a mild ductal dilatation. Moving echogenic forms in the dilated bile ducts were observed by ultrasound from 9 weeks postinfection in seven of the eight sheep. Moving worms were only demonstrated in four sheep at CT and in a single sheep at MRI. This study shows that radiological findings may be useful in studies of fluke-induced liver damage.

Efficacy of nitroxynil against Fasciola hepatica resistant to triclabendazole in a naturally infected sheep flock

“…Recently, McConville et al (2009) also described an increased in serum levels of the enzyme in experimental infected animals. In case of AST and ALT, these enzymes are correlated with the migration of the immature forms after the host infection (Ferre et al 1996;Gonzalo-Orden et al 2003;Değer et al 2008). These enzymes were constant in all groups until day 38 pt when slight increases were produced in both cases.…”

Hematological and biochemical changes in organically farmed sheep naturally infected with Fasciola hepatica

“…At the same time the activity of AST was because of a short half-life in the plasma, already within the reference limits for sheep, indicating young flukes have migrated through the liver parenchyma. Gonzalo-Orden et al (2003) observed that AST activity returned to normal values 11 weeks postinfection while Ferre et al (1995) reported AST to be significantly elevated even 14 weeks postinfection. On the other hand, serum activity of GGT still remained elevated at 18 weeks postinfection.…”

A rare cause of obstructive jaundice: Fasciola hepatica mimicking cholangiocarcinoma

“…Immunoserological tests are valuable in the early hepatic stage, but enzyme linked immunosorbent assay (ELISA) testing is more rapid and reliable (14,15). The typical radiological imaging of fascioliasis is more likely to be correctly reported by radiologists in areas in which the disease is prevalent (16,17). The infection can be shown more easily by endoscopic retrograde cholangiopancreatography (ERCP), during which a filling defect can be identified in the common bile duct.…”