Opistorchis viverrini


  • a.k.a. "southeast asian liver fluke" (endemic)
  • Trematode
  • Also within genus: opisthorchis felineus (Europe/Asia incl Russia) [1]

Life Cycle

  • Eggs pass in feces → freshwater snail ingestion → larval trematode embeds in fish skin/flesh → Fish consumed raw → duodenal cyst and subsequent biliary infection
  • Fluke count may effect clinical presentation (lower counts more asymptomatic)

Risk Factors

  • Exposure to endemic areas (see above)
  • Consumption of raw/undercooked fish

Clinical significance

  • May have acute infectious phase
  • Source of mild and moderate GI disease
  • Chronic infection predisposes to cholangitis, cholcystitis, cholangiocarcinoma (rare)

Clinical Features

  • Mild: dyspepsia, diarrhea, abdominal pain, constipation
  • Moderate: hepatomegaly, malnutrition
  • Felineus species may have an acute phase: alike to schistosomiasis (fever, facial edema, lymphadenopathy, arthralgias, rash, and eosinophilia) and involvement may extend to pancreatic duct in chronic cases

Differential Diagnosis

Helminth infections

Cestodes (Tapeworms)

Trematodes (Flukes)

Nematodes (Roundworms)



  • Praziquantel, 75mg/kg/day orally for 2 days (adults/pediatric) with meal[1]


  • Albendazole, 10mg/kg/day orally for 7 days (adults/pediatric) with meal [non-FDA alternative][1]
  • Identical to treatment for Clonorchis [2]
  • In cases of clonorchis in China, Trebindamine 400mg once has less side effects and equal efficacy (not available in U.S.) [3] [4]

See Also