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Giant fluke is a worm that parasitizes in the human body mainly in the liver, which causes acute and chronic violations of the liver, as well as other organs. This parasite is widespread in Africa and Asia, but there are also possible cases of infection in Russia and Ukraine. It is necessary to know some features of its cycle to predict not only the course of symptoms, but also possible methods of prevention at different stages.
Structure of the giant fluke
Giant fluke or Fasciola gigantica is a parasite that belongs to flukes or flat worms of the genus Trematodes. The features of their life cycle and structure make it possible to unite them in one genus with other parasites - schistosomes, opisthorhs.
The peculiarities of the structure of the giant fluke are such that from their class these parasites can be of the largest size. The length of an adult specimen of a giant fluke can be about seven centimeters. Their body has an elongated shape, in the form of a leaf of a tulip - at the ends a constriction. The color of the worm can be from pale pink to gray, depending on the conditions. The name "flukes" these parasites got because they have suckers on the front of the abdominal end. Between these suckers is the oral end, through which food comes. The digestive system is a closed fluke, that is, there is a digestive tube, where the main processes of digestion of food take place. Further, this food moves through the intestine through the entire length of the body, and after digestion back is thrown out through the mouth opening. Such features allow long-term parasitism in confined spaces without access to oxygen. This localization is also explained by the not fully developed system of hematopoiesis and respiration, which allows us to stay without oxygen for a long time and migrate through human vessels, feeding on red blood cells and other blood cells.
Giant fasciola reacts to the movement and change in the shape of the body due to a branched nervous system. It begins near the oral sucker in the form of a ring of nerve tissue, from which throughout the length of the entire body there is a nerve ganglion. Thus, all organs are innervated by this ganglion, and also the reaction of the analyzers is provided.
Reproduction of the parasite is complex, since the giant fluke is a hermaphrodite. There are individuals of female and male gender. For reproduction, it is necessary that there are favorable conditions for this, and some time passes for the fertilization of the eggs. Further, the peculiarities of the change of hosts allow us to pass through successive stages for the development of fasciolae.
Life cycle of the giant fluke
The life cycle of a giant fluke begins with the main host, which is large and small cattle - goats, sheep, cows, bulls, buffaloes. These worms are localized in the intestines of cattle, and then persist for some time they mature and become sexually mature. In this state, they are able to migrate through the wall of the intestine and enter the portal vein system. So the parasite enters the liver, where its final location is localized. There, the parasite reproduces and emits eggs that can pass back into the intestine through the bile duct system and stand out with feces. So with feces eggs are allocated, which are not pathogenic for a person until they fully ripen. Further, eggs enter fresh water, where warm water is needed for further development. In water, the larva grows and develops for two days, then it is necessary that it enter the body of the mollusk. There is a further development of fluke, where it reaches the stage of a larva invasive to humans.
Ways of infection of people with a giant fluke are limited to indirect paths, when a person accidentally encounters a terrain where the parasite is found. In this case, you can catch alimentary by eating vegetables, fruits, greens, which has on its surface larva fasciolae. It is also possible to contaminate with the occasional use of water in which these parasites float. These life cycle features must be considered in order to know the main ways of transmission and how to prevent the disease.
The characteristic localization of the parasite in the body of the final host promotes the same localization in the human body. Therefore, there are some specific symptoms of fascioliasis, which are characteristic for the defeat of this group of flukes.
Upon entering the human intestine, giant fasciolae eggs develop and grow, then they enter the submucosal layer at the larval stage and are absorbed into the blood. With blood flow through the portal vein system, the parasite enters the liver where it is updated. There is a further growth of larvae, their activation - in this state they are able to move along the ducts and enter the gallbladder, during which the normal arrangement of the duct and their relationship is disturbed. The function of bile outflow is violated in the first place, and as a secondary process bile stagnation occurs and the function of the liver itself is disrupted.
The incubation period lasts from a few days to five to seven weeks. In this case, a person may not remember the fact of infection, which makes diagnosis very difficult. This period lasts from the moment of getting into the intestine before activation in the liver and the violation of its function.
The acute stage of the disease develops at a single-stage massive liver injury with a significant number of parasites. In this case, the symptoms are very pronounced. There is jaundice, which causes patients to consult a doctor. It is accompanied by the itching of the skin, since the release of bile acids into the blood is expressed. At the same time, there are symptoms of pain in the right side or right upper quadrant, the severity of the pain syndrome increases with the use of fatty foods. Pain can also be blunt, mild. Often an attendant symptom is an allergic rash. This symptom is often observed due to the ability of helminths to cause increased allergization of the body, which is more often manifested by a diffuse rash all over the body with itching of the skin. Also, with an acute course, dyspeptic phenomena can occur-bitter taste in the mouth, nausea, vomiting, abdominal pain, and stool discomfort by the type of diarrhea.
But such an expanded clinic is less common than latent flow. Often, with a small number of parasites, there are little expressed symptoms, maybe only asthenovegetative syndrome, which can not be explained. In this case, a chronic form is formed, which is characterized by a slow constant release of eggs into the lumen of the intestine, and then reinfection. With this, there can be no symptoms on the part of the liver, only changes in allergic reactivity and the formation of a predisposition to stone formation and chronic cholecystitis in the gallbladder are expressed.
Diagnosis of this pathology should be complete and timely, because at the initial stage of development it is easier to act on a small number of worms. For the beginning it is necessary to carefully collect an anamnesis, finding out the possible etiological factors of infection. Given the incubation period, it is necessary to find out an anamnesis for the last two months. Next, you need to examine the patient and detail the complaints. On examination, you can identify positive cystic symptoms, tenderness in the right upper quadrant, but the liver should not increase.
Instrumental diagnostic methods are more informative in terms of diagnosing not only parasitic fasciola, but also in terms of assessing the state of the bile duct and liver. With ultrasound of the liver and bile ducts, the expansion of the duct is determined, the formation of echo-positive shadows in the projection of these ducts, a violation of the outflow of bile, and a reactive gallbladder. Based on this, one can suspect the presence of a parasite.
A laboratory blood test is not specific, but there are also possible changes in the form of eosinophilia, which can confirm the etiology of helminthic invasion. With severe jaundice, the patient needs a biochemical blood test. An increase in the level of bilirubin due to its direct fraction, as well as an increase in alkaline phosphatase, as a sign of cholestasis and intra-parasitic parotitis of the fluke is determined. The most specific and sensitive method for diagnosing a giant fluke is a blood test and a polymerase chain reaction. This determines the qualitative and quantitative presence of the worm in the body in the form of its DNA. This allows you to identify the antibodies or the antigen itself in the human body and accurately identify the pathogen.
These are the main methods of diagnosing this pathology, which must be used with the initial symptoms of the disease to prevent the chronic course of the pathology.
Treatment of any helminthic invasion should only be carried out in conjunction with other agents that prepare the gastrointestinal tract for dehylmensis. Therefore, you need to start with a diet that cleanses the intestines. It is necessary at the time of treatment to completely limit the sweet, flour foods. You need to eat porridge and cooked vegetables, which stimulate the intestinal peristalsis. After this, it is advisable to conduct a course of piercing therapy. To do this, it is necessary to conduct a single course with the use of laxatives. It is better to take herbal preparations with laxative effect. Then it is recommended to use a course with treatment with sorbents by taking them for three days. You can use Sorbex, White Coal, Polysorb. After such a course of purification therapy go to the treatment of the most helminthic invasion. Use anthelmintic drugs, which have a predominant effect on flatworms and their larval forms.
- Geoxychol is a drug that is especially active in the localization of parasitic worms in the liver. It is available in the form of a powder. The treatment regimen for this drug can be a three-day, five-day and ten-day treatment. The three-day scheme is most effective, since it allows you to create the maximum concentration of the drug in the shortest possible time. In this case, the drug is prescribed in a daily dose of 0.2 milligrams per kilogram of body weight of the patient. The drug is taken three times a day. The first dose should be taken after a light breakfast, dissolving the powder with a glass of warm milk. After three days of treatment it is necessary to adhere to the diet for at least a week, which will save the result and improve the body's response to the drug. When treating this drug, you need to monitor not only the dynamics of clinical symptoms, but also biochemical analysis with the level of bilirubin and transaminases.
- Thiabendazole is a broad-spectrum anthelminthic agent that is active against not only adult worms, but also larvae. This drug is available in the form of tablets of 500 milligrams, the dosage of the drug - two tablets twice a day with a course of treatment for three days. Thus, the maximum dose of the drug for one course should not exceed 6 grams. Possible side effects during the administration of the drug in severe helminthic invasion - nausea, abdominal pain, itching of the skin, as well as severe intoxication with increased lymph nodes, dizziness and subfebrile temperature. Children under five years of age should not use this medication, nor can they be used during pregnancy.
Given the predominant liver damage and the violation of intrahepatic bile outflow, it is recommended the use of hepatoprotectors and drugs to improve the outflow of bile. For this purpose it is recommended to use "Ursofalk" to improve the outflow of bile, which normalizes the function of the duct and relieves the symptoms of jaundice. From the group of hepatoprotectors, you can use "Enerliv", "Liver", "Gepabene", "Heptral". Together with the improvement of liver function, it is necessary to normalize the work of the intestine after the cleansing course, which will help the faster elimination of the parasite. Therefore, probiotics are also used in complex therapy.
Prevention of the giant fluke
Prevention of infection with a giant two-piece can be nonspecific and specific. Nonspecific methods of prevention are very simple - you need to adhere to hygiene rules, wash fruits and vegetables before consumption, and avoid water intake from untreated sources. Specific prophylaxis can be performed by any antiparasitic drug twice a year in spring and autumn, using preventive doses of the drug.
Giant fluke is a parasite from a group of flatworms that is localized in the liver and bile ducts with impaired function of bile outflow and the development of clinical symptoms. Infection of the person occurs not often, as the final owner is the cattle. Symptoms of the pathology can be hidden or obvious, which requires proper diagnosis. Treatment of giant fluke should be aimed at eliminating the parasite, restoring the function of the liver and intestines.