Opisthorchiasis

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Opisthorchiasis
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Opisthorchiasis is a parasitic disease caused by certain species of genus Opisthorchis (specifically, Opisthorchis viverrini and Opisthorchis felineus ). Chronic infection may lead to cholangiocarcinoma, a cancer of the bile ducts.

Contents

Medical care and loss of wages caused by Opisthorchis viverrini in Laos and in Thailand costs about $120 million annually. [1] In Asia, infection by Opisthorchis viverrini and other liver flukes affects the poorest people. [2] Along with other foodborne trematode infections such as clonorchiasis, fascioliasis and paragonimiasis, [3] opisthorchiasis is listed among the World Health Organization's list of neglected tropical diseases. [2]

Signs and symptoms

Symptoms of opisthorchiasis/clonorchiasis Symptoms of Raw fish infection.svg
Symptoms of opisthorchiasis/clonorchiasis

Symptoms of opisthorchiasis are indistinguishable from clonorchiasis. [4] About 80% of infected people have no symptoms, though they can have eosinophilia. [1] Asymptomatic infection can occur when there are less than 1000 eggs in one gram of feces. [1] Infection is considered heavy when there are 10,000-30,000 eggs in one gram of feces. [1] Symptoms of heavier infections may include diarrhea, epigastric and right upper quadrant pain, lack of appetite, fatigue, yellowing of the eyes and skin and mild fever. [1]

These parasites are long-lived and cause heavy chronic infections that may lead to accumulation of fluid in the legs (edema) and in the peritoneal cavity (ascites), [1] enlarged non-functional gallbladder [1] and also ascending cholangitis, which can lead to periductal fibrosis, cholecystitis and cholelithiasis, obstructive jaundice, hepatomegaly and/or portal hypertension.[ citation needed ]

Chronic opisthorchiasis and cholangiocarcinoma

Incidence of cholangiocarcinoma and O. viverrini in Thailand from 1990-2001. Incidence of CCA and O. viverrini in Thailand from 1990-2001-french.svg
Incidence of cholangiocarcinoma and O. viverrini in Thailand from 1990–2001.

Both experimental and epidemiological evidence strongly implicates Opisthorchis viverrini infections in the etiology of a malignant cancer of the bile ducts (cholangiocarcinoma) in humans which has a very poor prognosis. [5] Clonorchis sinensis and Opisthorchis viverrini are both categorized by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens. [6]

In humans, the onset of cholangiocarcinoma occurs with chronic opisthorchiasis, associated with hepatobiliary damage, inflammation, periductal fibrosis and/or cellular responses to antigens from the infecting fluke. [5] These conditions predispose to cholangiocarcinoma, possibly through an enhanced susceptibility of DNA to damage by carcinogens. Chronic hepatobiliary damage is reported to be multi-factorial and considered to arise from a continued mechanical irritation of the epithelium by the flukes present, particularly via their suckers, metabolites and excreted/secreted antigens as well as immunopathological processes. In silico analyses using techniques of genomics and bioinformatics is unraveling information on molecular mechanisms that may be relevant to the development of cholangiocarcinoma. [7]

In regions where Opisthorchis viverrini is highly endemic, the incidence of cholangiocarcinoma is unprecedented. [5] For instance, cholangiocarcinoma represents 15% of primary liver cancer worldwide, but in Thailand's Khon Kaen province, this figure escalates to 90%, the highest recorded incidence of this cancer in the world. Of all cancers recorded worldwide in 2002, 0.02% were cholangiocarcinoma caused by Opisthorchis viverrini. [5] Cancer of the bile ducts caused by opisthorchiasis occurs in the ages 25–44 years in Thailand. [8] A few cases have appeared in later life among U.S. veterans of the Vietnam War, who consumed poorly cooked fish from streams in endemic areas near the border of Laos and Vietnam. [9]

Diagnosis

The medical diagnosis is usually established by finding eggs of Opisthorchis viverrini in feces [1] using the Kato technique. [8] Alternatively, an antigen of Opisthorchis viverrini can be detected by ELISA test. [1] A polymerase chain reaction test that can be performed on faeces has been developed and evaluated in a rural community in central Thailand. [10]

Prevention

Cholangiocarcinoma is typically incurable at diagnosis. [11] [12] Because of this, intervention strategies are focused on the prevention or treatment of liver fluke infection. Prevention can be accomplished through education (by persuading people not to consume raw or undercooked fish), but the ancient cultural custom to consume raw, undercooked or freshly pickled fish persists in endemic areas. One community health program, known as the Integrated Opisthorchiasis Control Program, has achieved success in the Lawa Lakes region south of Khon Kaen. [13]

Cooking or deep-freezing (-20 °C for 7 days) [14] of food made of fish is an effective method of prevention. [1] Methods for prevention of Opisthorchis viverrini in aquaculture fish ponds have also been proposed. [15]

Treatment

Treatment of opisthorchiasis is usually accomplished with praziquantel. A single dose of praziquantel of 40 mg/kg is effective against opisthorchiasis (and also against schistosomiasis). [8] Despite the efficacy of this compound, the lack of acquired immunity to infection predisposes humans to reinfection in endemic regions. In addition, under experimental conditions, the treatment of Opisthorchis viverrini-infected hamsters with praziquantel induced a dispersion of parasite antigens, resulting in adverse immunopathological changes following re-infection with Opisthorchis viverrini, a process which has been proposed to initiate and/or promote the development of cholangiocarcinoma in humans. [7] Albendazole can be used as an alternative. [16]

A randomized controlled trial published in 2011 showed that tribendimidine, a broad-spectrum anthelmintic, appears to be at least as efficacious as praziquantel. [17] Artemisinin was also found to have anthelmintic activity against Opisthorchis viverrini. [18]

Epidemiology

Opisthorchiasis is prevalent where raw cyprinid fishes are a staple of the diet. [19] Prevalence rises with age; children under the age of 5 years are rarely infected by Opisthorchis viverrini. Males may be affected more than females. [20] [21] The WHO estimates that foodborne trematodiases (infection by worms or "flukes", mainly Clonorchis , Opisthorchis , Fasciola and Paragonimus species) affect 56 million people worldwide and 750 million are at risk of infection. [22] [23] 80 million people are at risk of opisthorchiasis (67 million from infection with Opisthorchis viverrini in Southeast Asia and 13 million from Opisthorchis felineus in Kazakhstan, Russia, and Ukraine). [24] [25] In the lower Mekong River basin, the disease is highly endemic, and more so in lowlands, [19] with a prevalence up to 60% in some areas of northeast Thailand. However, estimates using polymerase chain reaction-based diagnostic techniques indicate that prevalence is probably grossly underestimated. [26] In one study from the 1980s, a prevalence of over 90% was found in persons greater than 10 years old in a small village near Khon Kaen in northeast Thailand in the region known as Isan. [27] Sporadic cases have been reported from Malaysia, Singapore, and the Philippines. [23] Although the overall prevalence has declined since initial surveys performed in the 1950s, an increase has occurred since the 1990s in some areas, possibly related to large increases in aquaculture. [25]

Research

Using CRISPR gene editing technology in animal models, researchers have been able to eliminate the genes responsible for symptoms of opisthorchiasis, which may lead to further research toward novel treatment and control of this disease and its sequelae. [28]

Related Research Articles

<span class="mw-page-title-main">Trematoda</span> Class of parasitic flatworms

Trematoda is a class of flatworms known as flukes or trematodes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish.

<i>Clonorchis sinensis</i> Species of fluke

Clonorchis sinensis, the Chinese liver fluke, is a liver fluke belonging to the class Trematoda, phylum Platyhelminthes. It infects fish-eating mammals, including humans. In humans, it infects the common bile duct and gall bladder, feeding on bile. It was discovered by British physician James McConnell at the Medical College Hospital in Calcutta (Kolkata) in 1874. The first description was given by Thomas Spencer Cobbold, who named it Distoma sinense. The fluke passes its lifecycle in three different hosts, namely freshwater snail as first intermediate hosts, freshwater fish as second intermediate host, and mammals as definitive hosts.

<span class="mw-page-title-main">Praziquantel</span> Medication

Praziquantel (PZQ), sold under the brandname Biltricide among others, is a medication used to treat a number of types of parasitic worm infections in mammals, birds, amphibians, reptiles, and fish. In humans specifically, it is used to treat schistosomiasis, clonorchiasis, opisthorchiasis, tapeworm infections, cysticercosis, echinococcosis, paragonimiasis, fasciolopsiasis, and fasciolosis. It should not be used for worm infections of the eye. It is taken by mouth.

<span class="mw-page-title-main">Clonorchiasis</span> Infectious disease caused by fish parasites

Clonorchiasis is an infectious disease caused by the Chinese liver fluke and two related species. Clonorchiasis is a known risk factor for the development of cholangiocarcinoma, a neoplasm of the biliary system.

<span class="mw-page-title-main">Fasciolopsiasis</span> Medical condition

Fasciolopsiasis results from an infection by the trematode Fasciolopsis buski, the largest intestinal fluke of humans, growing up to 7.5 cm (3.0 in) long.

Metagonimiasis is a disease caused by an intestinal trematode, most commonly Metagonimus yokagawai, but sometimes by M. takashii or M. miyatai. The metagonimiasis-causing flukes are one of two minute flukes called the heterophyids. Metagonimiasis was described by Katsurasa in 1911–1913 when he first observed eggs of M. yokagawai in feces. M. takahashii was described later first by Suzuki in 1930 and then M. miyatai was described in 1984 by Saito.

<span class="mw-page-title-main">Tribendimidine</span> Chemical compound

Tribendimidine is a broad-spectrum anthelmintic agent developed in China, at the National Institute of Parasitic Diseases in Shanghai. It is a derivative of amidantel.

Opisthorchis viverrini, common name Southeast Asian liver fluke, is a food-borne trematode parasite from the family Opisthorchiidae that infects the bile duct. People are infected after eating raw or undercooked fish. Infection with the parasite is called opisthorchiasis. O. viverrini infection also increases the risk of cholangiocarcinoma, a cancer of the bile ducts.

<i>Echinostoma</i> Genus of flukes

Echinostoma is a genus of trematodes (flukes), which can infect both humans and other animals. These intestinal flukes have a three-host life cycle with snails or other aquatic organisms as intermediate hosts, and a variety of animals, including humans, as their definitive hosts.

<i>Opisthorchis felineus</i> Species of fluke

Opisthorchis felineus, the Siberian liver fluke or cat liver fluke, is a trematode parasite that infects the liver in mammals. It was first discovered in 1884 in a cat's liver by Sebastiano Rivolta of Italy. In 1891, Russian parasitologist, Konstantin Nikolaevich Vinogradov (1847–1906) found it in a human, and named the parasite a "Siberian liver fluke". In the 1930s, helminthologist Hans Vogel of Hamburg published an article describing the life cycle of Opisthorchis felineus. Felineus infections may also involve the pancreatic ducts. Diagnosis of Opisthorchis infection is based on microscopic identification of parasite eggs in stool specimens. Safe and effective medication is available to treat Opisthorchis infections. Adequately freezing or cooking fish will kill the parasite.

<span class="mw-page-title-main">Liver fluke</span> Group of liver parasites

Liver fluke is a collective name of a polyphyletic group of parasitic trematodes under the phylum Platyhelminthes. They are principally parasites of the liver of various mammals, including humans. Capable of moving along the blood circulation, they can occur also in bile ducts, gallbladder, and liver parenchyma. In these organs, they produce pathological lesions leading to parasitic diseases. They have complex life cycles requiring two or three different hosts, with free-living larval stages in water.

<i>Heterophyes heterophyes</i> Species of fluke

Heterophyes heterophyes, or the intestinal fish fluke, was discovered by Theodor Maximaillian Bilharz in 1851. This parasite was found during an autopsy of an Egyptian mummy. H. heterophyes is found in the Middle East, West Europe and Africa. They use different species to complete their complex lifestyle. Humans and other mammals are the definitive host, first intermediate host are snails, and second intermediate are fish. Mammals that come in contact with the parasite are dogs, humans, and cats. Snails that are affected by this parasite are the Cerithideopsilla conica. Fish that come in contact with this parasite are Mugil cephalus, Tilapia milotica, Aphanius fasciatus, and Acanthgobius sp. Humans and mammals will come in contact with this parasite by the consumption of contaminated or raw fish. This parasite is one of the smallest endoparasite to infect humans. It can cause intestinal infection called heterophyiasis.

<i>Bithynia siamensis</i> Species of gastropod

Bithynia siamensis is a species of a freshwater snail with a gill and an operculum, an aquatic prosobranch gastropod mollusk in the family Bithyniidae.

<span class="mw-page-title-main">Koi (dish)</span> Lao-Thai salad dish with raw beef

Koi is a "salad" dish of the Lao people living in modern-day Laos and Isan, Thailand, consisting of raw meat denatured by acidity, usually from lime juice. Common varieties include koi kung, with shrimp as the main ingredient, and koi paa /koi pla, which consists of minced or finely chopped raw fish in spicy salad dressing.

<span class="mw-page-title-main">Trematodiasis</span> Medical condition

Trematodiasis is a group of parasitic infections due different species of flukes, the trematodes. Symptoms can range from mild to severe depending on the species, number and location of trematodes in the infected organism. Symptoms depend on type of trematode present, and include chest and abdominal pain, high temperature, digestion issues, cough and shortness of breath, diarrhoea and change in appetite.

Banchob Sripa is a Thai scientist who is professor and head of the Tropical Disease Research Laboratory (TDRL) at Khon Kaen University in Khon Kaen, Thailand. He is also the head of the World Health Organization Collaborating Centre for Research and Control of Opisthorchiasis, an infectious parasitic disease caused by the Southeast Asian liver fluke, which is endemic in northeastern Thailand and other portions of the Mekong River basin. He is also coordinator for the Asian Neglected Tropical Disease Network. He has a doctorate in tropical health from the University of Queensland, Australia. He received the Outstanding Scientist Award from the Foundation for the Promotion of Science and Technology in 2013.

The Integrated Opisthorchiasis Control Program, commonly known as the "Lawa Project", located in Khon Kaen Province, Thailand, is an effort to reduce chronic infection by the Southeast Asian liver fluke among the native peoples of Isan, the northeast region of Thailand. The project operates under the aegis of the Tropical Disease Research Laboratory, Department of Pathology, Faculty of Medicine, Khon Kaen University. It is directed by Banchob Sripa. Its aim is to eliminate the practice of consuming raw or undercooked fish, the major cause of liver fluke infection and bile duct cancer in the region. The project is unique in that it follows the principles of EcoHealth, a One Health approach to improving human and animal health. The project has been the subject of newspaper and TV reports by BBC, The New York Times, and The Guardian.

Carcinogenic parasites are parasitic organisms that depend on other organisms for their survival, and cause cancer in such hosts. Three species of flukes (trematodes) are medically-proven carcinogenic parasites, namely the urinary blood fluke, the Southeast Asian liver fluke and the Chinese liver fluke. S. haematobium is prevalent in Africa and the Middle East, and is the leading cause of bladder cancer. O. viverrini and C. sinensis are both found in eastern and southeastern Asia, and are responsible for cholangiocarcinoma. The International Agency for Research on Cancer declared them in 2009 as a Group 1 biological carcinogens in humans.

<span class="mw-page-title-main">Paul Brindley (biologist)</span>

Paul J Brindley is an Australian parasitologist, microbiologist, and helminthologist. He is professor of Microbiology, Immunology, and Tropical Medicine at the George Washington University.

<span class="mw-page-title-main">Gastropod-borne parasitic disease</span> Medical condition

Gastropod-borne parasitic diseases (GPDs) are a group of infectious diseases that require a gastropod species to serve as an intermediate host for a parasitic organism that can infect humans upon ingesting the parasite or coming into contact with contaminated water sources. These diseases can cause a range of symptoms, from mild discomfort to severe, life-threatening conditions, with them being prevalent in many parts of the world, particularly in developing regions. Preventive measures such as proper sanitation and hygiene practices, avoiding contact with infected gastropods and cooking or boiling food properly can help to reduce the risk of these diseases.

References

  1. 1 2 3 4 5 6 7 8 9 10 Muller R. & Wakelin D. (2002). Worms and human disease. CABI. page 43-44.
  2. 1 2 Sripa, B. (2008). Loukas, Alex (ed.). "Concerted Action is Needed to Tackle Liver Fluke Infections in Asia". PLOS Neglected Tropical Diseases. 2 (5): e232. doi: 10.1371/journal.pntd.0000232 . PMC   2386259 . PMID   18509525..
  3. ↑ "Foodborne trematode infections". WHO . Retrieved 5 September 2018.
  4. ↑ King, S.; Scholz, T. Š. (2001). "Trematodes of the family Opisthorchiidae: A minireview". The Korean Journal of Parasitology. 39 (3): 209–221. doi:10.3347/kjp.2001.39.3.209. PMC   2721069 . PMID   11590910.
  5. 1 2 3 4 Sripa, B; Kaewkes, S; Sithithaworn, P; Mairiang, E; Laha, T; Smout, M; Pairojkul, C; Bhudhisawasdi, V; Tesana, S; Thinkamrop, B; Bethony, JM; Loukas, A; Brindley, PJ (July 2007). "Liver fluke induces cholangiocarcinoma". PLOS Medicine. 4 (7): e201. doi: 10.1371/journal.pmed.0040201 . PMC   1913093 . PMID   17622191. Open Access logo PLoS transparent.svg
  6. ↑ "IARC Monographs on the Evaluation of Carcinogenic Risks to Humans". monographs.iarc.fr. Retrieved 17 July 2017.
  7. 1 2 Young, ND; Campbell, BE; Hall, RS; Jex, AR; Cantacessi, C; Laha, T; Sohn, WM; Sripa, B; Loukas, A; Brindley, PJ; Gasser, RB (22 June 2010). "Unlocking the transcriptomes of two carcinogenic parasites, Clonorchis sinensis and Opisthorchis viverrini". PLOS Neglected Tropical Diseases. 4 (6): e719. doi: 10.1371/journal.pntd.0000719 . PMC   2889816 . PMID   20582164. Open Access logo PLoS transparent.svg
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  9. ↑ "Still Fighting: Vietnam Vets Seek Help for Rare Cancer". The New York Times. 11 November 2016. Retrieved 19 November 2016.
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  11. ↑ Zhang, Tan; Zhang, Sina; Jin, Chen; et al. (2021). "A Predictive Model Based on the Gut Microbiota Improves the Diagnostic Effect in Patients with Cholangiocarcinoma". Frontiers in Cellular and Infection Microbiology. 11: 751795. doi: 10.3389/fcimb.2021.751795 . PMC   8650695 . PMID   34888258.
  12. ↑ "Bile Duct Cancer (Cholangiocarcinoma) Treatment". National Cancer Institute. 23 September 2020. Retrieved 29 May 2021.
  13. ↑ Head, Jonathan (13 June 2015). "Deadly dish: the dinner that can give you cancer". BBC News. Retrieved 20 November 2016.
  14. ↑ World Health Organization (2004). REPORT JOINT WHO/FAO WORKSHOP ON FOOD-BORNE TREMATODE INFECTIONS IN ASIA. Report series number: RS/2002/GE/40(VTN). 55 pp. PDF. pages 15-17.
  15. ↑ Khamboonruang, C.; Keawvichit, R.; Wongworapat, K.; Suwanrangsi, S.; Hongpromyart, M.; Sukhawat, K.; Tonguthai, K.; Lima Dos Santos, C. A. (1997). "Application of hazard analysis critical control point (HACCP) as a possible control measure for Opisthorchis viverrini infection in cultured carp (Puntius gonionotus)". The Southeast Asian Journal of Tropical Medicine and Public Health. 28 (Suppl 1): 65–72. PMID   9656352..
  16. ↑ "Opisthorchiasis - Treatment Information". CDC - DPDx. 2013-11-29. Retrieved 2015-09-07.
  17. ↑ Soukhathammavong, P.; Odermatt, P.; Sayasone, S.; Vonghachack, Y.; Vounatsou, P.; Hatz, C.; Akkhavong, K.; Keiser, J. (2011). "Efficacy and safety of mefloquine, artesunate, mefloquine–artesunate, tribendimidine, and praziquantel in patients with Opisthorchis viverrini: A randomised, exploratory, open-label, phase 2 trial" (PDF). The Lancet Infectious Diseases. 11 (2): 110–118. doi:10.1016/S1473-3099(10)70250-4. PMID   21111681.
  18. ↑ Keiser, J.; Utzinger, J. R. (2007). "Artemisinins and synthetic trioxolanes in the treatment of helminth infections". Current Opinion in Infectious Diseases. 20 (6): 605–612. doi:10.1097/QCO.0b013e3282f19ec4. PMID   17975411. S2CID   34591129..
  19. 1 2 Sithithaworn, P; Andrews, RH; Nguyen, VD; Wongsaroj, T; Sinuon, M; Odermatt, P; Nawa, Y; Liang, S; Brindley, PJ; Sripa, B (March 2012). "The current status of opisthorchiasis and clonorchiasis in the Mekong Basin". Parasitology International. 61 (1): 10–6. doi:10.1016/j.parint.2011.08.014. PMC   3836690 . PMID   21893213.
  20. ↑ Farrar, Jeremy; Hotez, Peter; Junghanss, Thomas; Kang, Gagandeep; Laloo, David; White, Nicholas (2013). Manson's tropical diseases (New ed.). Philadelphia: Saunders [Imprint]. ISBN   978-0702051012.
  21. ↑ Kaewpitoon, N; Kaewpitoon, SJ; Pengsaa, P (21 April 2008). "Opisthorchiasis in Thailand: review and current status". World Journal of Gastroenterology. 14 (15): 2297–302. doi: 10.3748/wjg.14.2297 . PMC   2705081 . PMID   18416453.
  22. ↑ "Foodborne trematodiases". World Health Organization. Archived from the original on September 15, 2012. Retrieved 26 November 2015.
  23. 1 2 Sripa, B; Kaewkes, S; Intapan, PM; Maleewong, W; Brindley, PJ (2010). "Food-borne trematodiases in Southeast Asia epidemiology, pathology, clinical manifestation and control". Advances in Parasitology. 72: 305–50. doi:10.1016/S0065-308X(10)72011-X. PMID   20624536.
  24. ↑ Keiser, J; Utzinger, J (July 2009). "Food-borne trematobiases". Clinical Microbiology Reviews. 22 (3): 466–83. doi:10.1128/cmr.00012-09. PMC   2708390 . PMID   19597009.
  25. 1 2 Keiser, J; Utzinger, J (October 2005). "Emerging foodborne trematodiasis". Emerging Infectious Diseases. 11 (10): 1507–14. doi:10.3201/eid1110.050614. PMC   3366753 . PMID   16318688.
  26. ↑ Johansen, MV; Sithithaworn, P; Bergquist, R; Utzinger, J (2010). "Towards improved diagnosis of zoonotic trematode infections in Southeast Asia". Advances in Parasitology. 73: 171–95. doi:10.1016/S0065-308X(10)73007-4. ISBN   9780123815149. PMID   20627143.
  27. ↑ Upatham, ES; Viyanant, V; Kurathong, S; Brockelman, WY; Menaruchi, A; Saowakontha, S; Intarakhao, C; Vajrasthira, S; Warren, KS (November 1982). "Morbidity in relation to intensity of infection in Opisthorchiasis viverrini: study of a community in Khon Kaen, Thailand". The American Journal of Tropical Medicine and Hygiene. 31 (6): 1156–63. doi:10.4269/ajtmh.1982.31.1156. PMID   6983303.
  28. ↑ "CRISPR/Cas9 shown to limit impact of certain parasitic diseases". www.bionity.com. Retrieved 2019-01-18.
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