Echinococcosis: Symptoms In Humans, Treatment And Diagnosis

2023 Author: Riley Dean | [email protected]. Last modified: 2023-11-27 09:15

Echinococcosis caused by echinococcus is a dangerous disease that can cause severe damage to internal organs in a person. Echinococcus can be infected by eating meat of wild and domestic animals that has not been heat treated. Symptoms of the ingestion of echinococcus into the body may not manifest themselves for a long time, and the first signs of the disease may appear only after a few months or years.

The content of the article:

1 Echinococcus - who is it
2 Ways of transmission of echinococcus
3 General symptoms caused by echinococcus
4 What is Echinococcosis of the liver
5 Features of liver echinococcosis
6 Causes of liver echinococcosis
7 Symptoms of liver echinococcosis
8 Diagnosis of liver echinococcosis
9 Treatment of liver echinococcosis
10 Prevention of liver echinococcosis

Echinococcus - who is it

So after all, what is echinococcosis? To clearly answer this question, it is necessary to understand the numerous types of parasites. Echinococci refer to tapeworms, parasitizing in the intestines of mainly dogs, wolves, foxes. The total dimensions of worms do not exceed a few millimeters, if you look closely, you can see them with the naked eye.

There are two types of echinococcus:

Hydatious echinococcosis - often affects the liver in humans
Alveolar echinococcosis - predominantly affects the lungs

In the human body, parasites exist only in the form of a larva, which looks like a single-chamber bladder (hydatious echinococcosis), or a multi-chamber bladder (alveolar echinococcosis). The bladder, or in other words, the echinococcal cyst consists of two membranes: external and internal. There is a liquid inside the bubble and new embryos - scolexes - float in it. In the inner shell there are special areas that have the ability to give birth to new larvae. The bladder slowly but surely increases in size, while squeezing the surrounding tissues and disrupting their functions.

Ways of transmission of echinococcus

During development, Echinococcus undergoes several stages, successively passing one into the other. Among domestic animals, the final owner is the dog, but in some cases it can also be found in cats. Mature worms parasitize in the intestines of these animals. Eggs, along with feces, are released into the environment and get to: on the ground, in water, vegetables, fruits, in general, on what comes into contact with feces in the external environment.

Further, the distribution paths diverge somewhat, there are several options:

One part of the eggs is swallowed by small rodents - rats, mice, muskrats. Once in the intestines, the larvae enter the bloodstream and are carried with the bloodstream into the liver, where they begin to mature. When wild animals eat these small animals, parasites infect them. When hunting, killed game can serve as a source of human infection, especially in those cases when hunters do not roast it well and then eat it

The other part enters the intestines of farm animals (goats, sheep, pigs, large and small ruminants), along with the eaten grass, contaminated feed, contaminated water. Inside their body, the larvae also enter the liver, lungs, and less often other organs, where they are for a long time. A person can freely become infected with echinococcus if he eats poorly thermally processed meat of infected animals.

The third way of spread, and I would say one of the most important, is non-observance of the rules of usual hygiene. When, for example, a child or an adult, without washing freshly picked strawberries, or playing with the dog in the yard, also does not wash his hands and begins to bite his nails or eat, then this category of people has every chance of contracting this disease

Once in the human body, the larvae are initially absorbed from the intestines and enter the liver. Most of the parasites cannot pass the hepatic barrier and remain.

General symptoms caused by echinococcus

Echinococcosis is not an acute illness that presents with a sudden high fever, chills, torrential sweats, or severe pain. No, on the contrary, the symptoms of the disease may not appear or be felt by an infected person for many months and even years from the moment of illness. This feature makes it difficult to make a correct diagnosis and often the patient turns to different specialists for help until he finally gets to the operating table for the removal of the echinococcal cyst.

The general symptoms of the disease include, first of all:

Weakness and increased fatigue
Decreased overall performance
Recurrent headaches
Rash on the skin in the form of small, punctate red spots
Increases in body temperature that are temporary

These symptoms are due to the release of toxic metabolic products of parasites, as well as the body's reaction to the introduction of infection into the human body.

What is Echinococcosis of the liver

Echinococcosis of the liver (echinococcosis hepatis) is human helminthiasis caused by the introduction and development of the larvae of the tapeworms Echinococcus granulosus and E. (Alveococcus) multilocularis in the liver.

Vesicular (unicameral, racemose, hydatidous) echinococcosis in about half of the cases occurs with liver damage, and the cyst is more often localized in the right lobe, occasionally several cysts are observed. The pathogenic effect of echinococcus on the body is determined by the mechanical pressure of the echinococcal cyst on the liver and adjacent organs, as well as by the toxic and sensitizing effects of the parasite.

Features of echinococcosis of the liver

Echinococcosis of the liver is a parasitic pathology that is caused by the tapeworm Echinococcus. Its larvae invade and multiply in organ tissue, forming cysts. This disease is considered one of the most common helminthiases. The incidence of echinococcosis in different countries of the world varies significantly.

The disease is mainly observed in regions where they are actively engaged in agricultural activities. Echinococcus parasitizes in the human body exclusively in the form of a larva, affecting not only the liver, but also other organs, such as the brain and lungs. Moreover, the involvement of the liver in the process occurs in 65% of all cases of this disease.

Gastroenterology and infectology are engaged in the study of pathology. Treatment of echinococcosis is included in the scope of activities of specialists such as an infectious disease specialist, gastroenterologist, hepatologist and surgeon.

Causes of liver echinococcosis

Echinococcosis of the liver can be infected in three ways. Before the introduction into the human body, the life cycle of echinococcus includes several stages that follow one after another. The final owner among pets is dogs and, much less often, cats. The parasite lives in the intestines of these animals in the form of mature worms.

Their eggs with feces pass into water bodies, soil, fruits, vegetables, and so on. In the future, there are several options for the entry of eggs into the human body. Some of the eggs are swallowed by small rodents. In the liver of these animals, the larvae of echinococcus begin to mature. After eating rodents by wild predators, the latter also become infected with parasites. Therefore, with poor heat treatment of game, hunters can get sick with liver echinococcosis.

Another part of the eggs of echinococcus appears in the digestive system of agricultural animals, such as pigs, cattle, etc. The eggs enter the mammalian body along with food, grass or water, affecting its organs. Therefore, eating meat without proper processing can cause the development of liver echinococcosis.

The most common and relevant for humans is the third way of the parasite entering the body. It is noted with insufficient adherence to hygiene rules, which is especially important for children.

Echinococcus can enter the gastrointestinal tract when eating unwashed fruits or playing with pets, after which the hands have not been thoroughly washed. In the human body, the larvae are initially absorbed into the bloodstream from the intestines and transferred to the liver. In the future, they contribute to the occurrence of liver echinococcosis. However, many parasites do not pass through the bloodstream through the hepatic barrier, but spread through the bloodstream to other organs.

Symptoms of liver echinococcosis

Echinococcosis of the liver is a chronic disease that does not have pronounced symptoms that make a person see a doctor in time. After infection, symptoms do not begin to appear immediately, but after several months or years.

Most often, patients are worried about general weakness, a decrease in exercise tolerance, a decrease in performance, pain in the head, a small pinpoint rash on the skin, a periodic slight increase in temperature. These clinical signs are a consequence of the ingestion of toxic waste products of echinococcus into the bloodstream and the body's reaction to the introduction of parasites.

The development of echinococcus in the liver occurs in several stages, each of which has its own clinical features. At the first stage, symptoms may not be observed at all. Therefore, the infected person feels normal and leads an active lifestyle. At this stage, echinococcus is introduced into the liver tissue and forms a protective capsule.

The only manifestation of the disease may be a slight discomfort in the right hypochondrium after eating a large amount of food. The second stage is characterized by clear clinical symptoms. In patients, appetite is disturbed and body weight gradually decreases. When taking medications in infected people, there may be a more frequent development of adverse reactions, which is associated with a decrease in the detoxification function of the liver against the background of echinococcosis.

Diagnostics of the liver echinococcosis

In the diagnosis of the hydatid form of echinococcosis, the patient's history helps (living in an area that is endemic for this disease). The decisive role is assigned to additional research methods. In a general blood test, eosinophilia (up to 20% and above) is often found. Intradermal Katzoni reaction with sterile echinococcal bladder fluid is used. The mechanism of this test is similar to the reaction to tuberculin in tuberculosis. Katsoni's test is positive in 75-85% of patients.

Approximately 1 year after the death of the parasite, the reaction becomes negative. The agglutination reaction with latex (synthetic polystyrene resin) and the indirect hemagglutination reaction are more accurate and informative. With plain radiography, one can note the high standing of the dome of the diaphragm or its protrusion, calcifications in the projection of the echinococcal cyst. More detailed information can be obtained by radiography under conditions of pneumoperitoneum.

The localization and size of the echinococcal cyst can be judged by the data of radioisotope hepatoscanning (a defect in the accumulation of the isotope will be seen at the site of the cyst projection). The most reliable and simple are ultrasonic echolocation and computed tomography. Among invasive research methods, laparoscopy and angiography are widely used. With celiacography, an arcuate repression of the liver vessels, characteristic of a mass formation, is found.

For the diagnosis of alveolar echinococcosis, a long-term "tumor" of the liver of extreme density, hypereosinophilia, liver scan and positive results of allergic tests are important. The reaction of Katsoni with an alveolar antigen has the greatest diagnostic value.

Treatment of liver echinococcosis

Echinococcosis of the liver is a parasitic disease that never goes away on its own. At the same time, conservative methods do not allow achieving complete recovery. Therefore, the only effective treatment is surgery. At the preparatory stage, before the operation and in the postoperative period, the appointment of the anthelmintic drug mebendazole is indicated. This drug inhibits the growth of the cyst, reduces its size, significantly reduces the risk of recurrence of the pathology.

The most effective treatment is surgical removal of the parasite. The operation is associated with a high risk of dissemination of the larvae to the surrounding tissues, therefore, it should be carried out by a specialist who knows the technique of minimally invasive aparasitic interventions using modern instruments.

Surgical techniques include excision of liver cysts and endoscopic drainage of liver cysts. After removal of the cyst, germicides are injected into the resulting cavity (80-100% glycerin and 30% sodium chloride solution are most effective to prevent recurrence of liver echinococcosis).

The best way to treat echinococcectomy. Ideal echinococcectomy, in which the entire cyst with its chitinous and fibrous membranes is removed without opening the lumen, is rarely used for small cysts and their marginal location. With large cysts located in the thickness of the liver tissue, this method is fraught with damage to large vessels and bile ducts.

Removal of the cyst with its germinal and chitinous membranes after preliminary puncture of the cyst cavity, with suction of its contents is often used. This technique avoids rupture and dissemination of the parasite when the cyst is isolated. After removal of the cyst, the fibrous membrane from the inside is treated with a 2% formalin solution and sutured with separate sutures from the inside (capitonage). If it is impossible to suture the cavity, they resort to tamponade with its omentum. In case of suppuration of the contents of the cyst after the completion of the main stage of the operation, the remaining cavity is drained. With large sizes of the cyst, as well as in the case of calcification of its walls, as a forced measure, they resort to marsupialization (stitching the walls of the cyst into the anterior abdominal wall).

The purpose of the operation is to radically remove the cyst along with the membranes and their contents without leaving scolexes and blisters in the liver, abdominal or chest cavity. The fibrous capsule is not removed in most cases. The volume of surgical interventions depends on the location, size, number and complications of cysts. In case of marginal localization of a cyst with calcification, an ideal echinococcectomy is performed together with a fibrous capsule according to A. V. Melnikov, possibly with the use of a CO2 laser.

With multiple echinococcosis and with the marginal arrangement of cysts, as well as giant cysts that occupy the entire lobe, atypical or anatomical resection of the liver is performed. With single cysts, even with giant ones, with cysts of both halves of the liver and with a festering cyst, the operation of choice is a one-stage closed echinococcectomy according to A. A. Bobrov and S. I. Spasokukotsky.

To prevent contamination with scolexes after puncture, the contents of the cyst are removed by echinococotomes, the fibrous capsule is not removed, the cavity is treated with various antiparasitic agents (2-5% formalin solution, 5% iodine solution, 96% alcohol, etc.), as well as cryoinfluence and defocused CO2- beam. laser.

Prevention of liver echinococcosis

The complex of veterinary and medical measures for echinococcosis is aimed primarily at identifying and eradicating the source of the invasion. In accordance with the official recommendations, we are talking about reducing the number of guard dogs, their registration, registration and destruction of stray animals.

Veterinary specialists of farms carry out preventive deworming of service dogs from December to April every 45 days, from May to November - every 30 days, the rest - once a quarter. These measures should also be taken with private dogs. Deworming is carried out on special sites, where the excreted feces are collected in a metal container and neutralized: (boil for 10 - 15 minutes, pour for 3 hours with a 10% solution of bleach, the soil is treated with a 3% solution of carbation (4 l per 1 m2).

To prevent the infection of dogs, it is necessary to follow the rules for slaughtering farm animals and ensure the destruction of the affected organs, as well as to prevent dogs from accessing the territory of meat processing plants, slaughterhouses, and cattle burial grounds.

Measures to prevent infection of dogs also include such mandatory recommendations as: increasing the veterinary and sanitary level of farms; construction of disposal pits, cattle burial grounds; compliance with the rules for storage and transportation of animal corpses; slaughter of animals only in appropriate places, etc.

Medical measures provide for the identification of decreed groups infested by examination (hunters, persons in contact with dogs, processing furs, making fur products, shepherds) and examination according to clinical indications; deworming and dispensary observation. Health education is of great importance.

Personal prevention of echinococcosis is to limit contact with dogs, play with children, wash your hands thoroughly after contact with animals, before eating after working in the garden, playing in the yard, in the garden, picking mushrooms, do not eat unwashed wild berries, do not drink unboiled water from natural reservoirs.

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