Opisthorchis viverrini


Lifecycle of Opisthorchis.
  • 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

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