Pathogenesis in extra-hepatic organs due to aberrant migration of Fasciola gigantica in sheep

Adult distome flukes belonging to the genus Fasciola usually inhabit the liver, bile ducts and gall bladder of their ruminant natural hosts. However, in unnatural hosts like humans, and cases of peracute fasciolosis in natural hosts, F. gigantica can erratically migrate to extra-hepatic sites and cause pathogenesis. This paper documents cases of peracute fasciolosis among sheep in a private farm, with lesions in extra-hepatic organs like lungs, heart and kidney. All examined cases were found to exhibit pulmonary involvement characterized by circular, haemorrhagic lesions extending into the lung parenchyma. Two cases of cardiac fasciolosis were documented in sheep for the first time, with cardiac tamponade resulting from accumulation of blood in the pericardial sac leading to death in one case. Haemorrhagic nephritis in sheep due to aberrant migration of a single immature F. gigantica into the subcapsular spaces of kidney was also recorded.