INTESTINAL PARASITES (Helminths)
TREMATODA Order: Opisthorchiata

OPISTHORCHIS FELINEUS

Brief update on Opisthorchis felineus infection
in Russia.

Fel1-ic

Opisthorchis felineus: an estimated 17 million of people on our planet
are infected with fishborne Opisthorchiidae trematode infections:
Opisthorchis felineus, O.viverrini, Clonorchis sinensis [1].
Despite being preventable fishborne trematode infection
Opisthorchis felineus is widespread in the Russia.
Opisthorchis felineus: adult fluke

Fel2-ic

Opisthorchis felineus was first found in 1884 in cat liver
in the Northern Italy by Rivolta and in 1891 in man in Siberia
by the Russian scientist K.N.Vinogradov who named it “Siberian liver fluke”
Opisthorchis felineus: adult fluke, detail

Fel3-ic

Opisthorchis felineus (Rivolta, 1884) is the most prevalent food-borne
liver-fluke infection of man in the Russia, Ukraine and Kazahstan.
Estimated number of persons infected with O.felineus in Russia is about 1,500,000 [2].
Opisthorchis felineus: adult fluke, detail

Fel4-ic

Opisthorchis felineus: opisthorchiasis is most prevalent in
Western Siberian region in the Ob and Irtish river valleys
where the prevalence amongst local natives
(Hanti, Mansi, Nensi - Mongoloid race)
in some settlements of this region reaches 100% and up
to 80 amongst nonaborigene indigenous population [3,4].
In the European Russia the endemic area is located between
Volga and Kama rivers and in some other regions where prevalence
of this infection varies from sporadic cases to 10% [2].
Opisthorchis felineus: adult fluke, detail

Fel5-ic

Opisthorchis felineus:  first intermediate hosts are freshwater snails - Bithyniidae;
second intermediate hosts are freshwater fish -Cyprinidae.
In Russia the most important second intermediate hosts are
Leuciscus idus L., Leuciscus leuciscus L. and Rutilus rutilus L..
Main second intermediate hosts from Ob and Irtish river valleys:
Leuciscus idus L. (in the middle); Leuciscus leuciscus L.(at the bottom)
and Rutilus rutilus L. (at the top).

Fel6-ic

Fel7-ic

Opisthorchis felineus: pathological manifestations of initial phase
of O.felineus infection are multiple and vary in both quality and intensity
from non-apparent form and acute cases with clinical manifestations.
The major pathology in O.felineus infection is chronic inflammation of the bile ducts.
Opisthorchis felineus. Metacercarias in culture (artificial digestion procedure).

Fel8-ic

Opisthorchis felineus: opisthorchiasis varies in severity from asymptomatic
infection to severe illness with appreciable morbidity and mortality.
In heavily infected patients recurrent pyogenic cholangitis, liver abscesses,
cholecystitis, pancreatitis, biliary stones may occur.
The absence of pathognomic clinical manifestations and confounding
of diagnosis with other prevalent diseases lead to under-reporting [3,5].
Opisthorchiasis is linked to cholangiocarcinoma,
but the pathogenesis is still unclear and liver cancer is one
of most common malignancies that occurs in endemic areas [1].
The outcome in patients with opisthorchiasis is dependent on early treatment
and hence the early detection of infection is important.
Opisthorchiasis parasitological techniques:
- stool and duodenal fluid surveys (photo 8),
examination of suspected fish - artificial digestion procedure (photo 7),
tissue compression between two slides (photo 6).
Praziquantel is the drug of choice for treatment of opisthorchiasis and clonorchiasis.
Opisthorchis felineus eggs (at x 400 magnification) in duodenal fluid
on the transparent polycarbonate Nucleopore membrane
(arrow indicates a filter pore (8 mm) )
Duodenal fluid was obtained by duodenal aspiration.