Liver parasites: A global endemic and journey from infestation to intervention

Table 2 Clinical features of trematodes

Parasite	Ref.	Global distribution	Hosts	Symptoms and complications	Diagnosis	Treatment
Fasciola hepatica	Peters et al[4]; Bargues and Mas-Coma[16]	Asia, Americas, Africa, Europe, Oceania	Lymnaea galba (water snail)	Abdominal pain, fever, nausea, urticaria, biliary tract obstruction, eosinophilia, jaundice, focal hepatic lesion	Stool microscopy, CT, antibodies, US, ERCP	Triclabendazole 10 mg/kg × 2 doses 12 hours apart, nitazoxanide 500 mg twice a day for 7 days
Fasciola gigantica	Peters et al[4]; Bargues and Mas-Coma[16]	Asia, Africa[4]	Lymnaea radix (water snail)[16]	Constitutional and hepatobiliary symptoms the same as Fasciola hepatica	Stool microscopy, CT, antibodies, US, ERCP	Triclabendazole 10 mg/kg × 2 doses 12 hours apart, nitazoxanide 500 mg twice a day for 7 days
Clonorchis sinesis	Locke et al[17]	East Asia	Freshwater fish (mainly cyprinidae family)	Calcium carbonate gallstones, pancreatitis, liver abscess, recurrent ascending cholangitis, cholangiocarcinoma	Stool microscopy, bile and serum IgG4, ERCP, ELISA, CT	Praziquantel 25 mg/kg orally 3 times a day, tribendimidine single dose of 400 mg, surgery or biliary stenting in case of cholangiocarcinoma
Ophisthorchis viverrine	Liau et al[18]	Southeast Asia	Freshwater snails (bithynia), Freshwater fish (cyprinidae)	Cholangitis, cholecystitis, periductal fibrosis, cholangiocarcinoma	Stool microscopy, urine antigen detection, US, CT, ERCP	Praziquantel 25 mg/kg orally 3 times a day, tribendimidine single dose of 400 mg
Schistosoma manson	Colley et al[19]	Africa, Middle East, Americas	Freshwater snails (biomphalaria species)	Symmers pipestem liver fibrosis, portal hypertension, gastroesophageal varices	Stool microscopy, US, circulating cathodic antigen assay	Praziquantel 20 mg/kg PO TID for 1 day
Schistosoma japonicum	Colley et al[19]	Asia	Freshwater snails (oncomelania species)	Periportal fibrosis, rectal bleeding, cerebral schistosomiasis (meningoencephalitis)	Stool microscopy, circulating cathodic antigen assay	Praziquantel 20 mg/kg PO TID for 1 day

CT: Computed tomography; ELISA: Enzyme-linked immunosorbent assay; ERCP: Endoscopic retrograde cholangiopancreatography; PO: Per oral; TID: Three times a day; US: Ultrasound.