Alveococcosis- This is helminthiasis, which is caused by one of the representatives of the type of flatworms, namely Alveococcus multilocularis. The human liver is primarily affected, then the alveococcus can pass to other organs (for example, the lungs, spleen, brain, heart, muscles, bones).
The most common cause of the disease: non-compliance with the simplest rules of personal hygiene. In particular, it is possible to become infected if animals are not properly kept (for example, dogs), when cutting carcasses or skins of infected animals. Less often, the ingestion of helminths is possible by the oral route, that is, when eating fruits, vegetables, wild berries and herbs contaminated with animal feces.
Symptoms of alveococcosis
Symptoms of alveococcosis in the early stages: aching pain in the liver of a periodic nature, nausea with vomiting, indigestion, upset stools, general fatigue, malaise. In the late stage, the symptoms are complicated by obstructive jaundice, chills, fever, liver abscesses, purulent cholangitis. In case of metastasis to other organs, there is a corresponding symptomatology of a violation of their functioning.
It is important to diagnose and treat alveococcosis as soon as possible in order to prevent the development of serious complications when the helminth spreads throughout the body. For accurate and timely diagnostics, our clinic uses all the main methods: analysis of blood, feces, X-ray and ultrasound methods, tomography of organs.
Alveococcosis treatment
The treatment of alveococcosis is complex, it includes surgery and specific drug therapy, but the qualified specialists of our clinic know how to get rid of this helminth in the shortest possible time and restore your health.
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Alveococcosis, or multi-chamber echinococcosis, is one of the most dangerous human helminthiases. It is characterized by a severe chronic course, primary tumor-like liver damage, often with metastases to the brain and lungs, as well as to many other organs. The disease is often fatal.
Etiology.
The causative agent of alveococcosis is the larval stage of the tapeworm Alveococcus multilocularis(Leuckart, 1858; Abuladse, 1960r.), Genus AIveococcus(Abuladse, 1960), subfamilies Echinococcine(Abuladse, 1960), family Taeniidae(Lud-wig, 1886), suborder Taeniata(Skryabin et Schulz, 1937), class Cestoidea(Rudolphi, 1808), a type of flatworm Plathelminthes(Schneider, 1873).
The sexually mature form of alveococcus reaches a length of 1.3 - 3.27 mm with the number of segments - from 3 to 5, in structure it is close to echinococcus. Distinctive signs of alveococcus from echinococcus are as follows: the number of hooks on the scolex - 28 - 32, more often 30; in a mature segment, its sac-shaped uterus or ball never has lateral protrusions; the genital opening is located in the anterior half of the lateral margin, and not in the posterior half of the echinococcus.
Oncospheres are similar to oncospheres of other members of the family Taeniidae.
The larval form of alveococcus is a node consisting of a conglomerate of microscopic vesicles formed by budding, tightly adjacent or fused with each other. The cavity of the bubbles is filled with a yellowish viscous liquid or a thick dark mass. In animals, there are scolexes in almost every vesicle, while in humans this is rare. In the section, the node has a cellular structure with necrotic decay in the center.
Life cycle.
The developmental cycle of alveococcus is very similar to the development of echinococcus, it is also associated with the change of two hosts, but different species.
The intermediate hosts in which the larval stage is developing are representatives of the order of wild mouse-like rodents (Rodentia)- muskrat, vole, hamster, ground squirrel, gerbil, nutria, beaver, etc., as well as a person who is a biological dead end.
By the 35th day, the oncospheres in the uterus of the mature terminal segment become invasive. Excretion of eggs with animal feces begins from the 33rd - 34th day, segments from the 53rd - 70th day, which with feces or actively crawl out of the owner's anal opening. At the same time, many oncospheres, freed from the membranes, are squeezed out through the anterior edge of the segment, in many remaining on the wool of the infected animal. The segment contains 200 - 800 eggs. Segment rejection occurs at approximately 14-day intervals. The segments that have fallen into the soil can spread within a radius of 0.25 m (like the segments of the echinococcus), leaving a trail of eggs on the ground and grass.
Infection of intermediate hosts occurs as a result of ingestion of oncospheres or mature segments.
Once in the digestive tract of the intermediate host (humans, rodents), oncospheres are freed from the outer shell, penetrate into the mucous membrane of the stomach or small intestine, penetrate into the blood or lymphatic capillaries, then into the portal vein and settle mainly in the liver, where the larvae form into larvocysts ... The possibility of a part of the oncospheres entering the inferior vena cava, into the right sub-heart and right ventricle of the heart and through the pulmonary circulation into the lungs, and parts into the systemic circulation is not excluded. Oncospheres can be brought into any other organs, however, primary alveococcosis of other organs is very rare.
The development of alveococcus larvocyst in humans occurs over a number of years, while in rodents it is completed in 30 - 40 days. Larvocyst growth is carried out by exogenous budding of vesicles, invading hepatic tissue like a malignant tumor. At the same time, the integrity of the blood vessels is disrupted, and the individual vesicles detached from the larvocyst are carried by the blood stream to other organs, most often to the brain, thus forming metastases, making the alveococcus look like a malignant tumor.
Pathogenesis.
Oncospheres of the alveococcus, which got orally into the alimentary canal, settle mainly in the right lobe of the liver. Damage to other organs (lungs, brain, kidneys, spleen, muscles, peritoneum, mesentery) is a consequence of metastasis.
The nodes formed in the liver are nodes of productive-necrotic inflammation of a whitish color, often of cartilaginous density, resemble spongy cheese on a cut (Bregadze I.L., Plotnikov N.N., 1976). The dimensions of the knot vary from 0.5 to 30 cm or more in diameter.
The alveococcal node can reach the surface of the liver and grow into adjacent organs (diaphragm, kidney, bones and tissues - extrahepatic metastasis.
When a secondary infection is attached, cholangitis, liver abscesses, suppuration and decay of the floor of the node occur. Sometimes cirrhosis of the liver develops. With the germination of the bile ducts, obstructive jaundice develops.
Clinic.
The clinical picture of liver alveococcosis is very diverse. In the initial period, the disease is asymptomatic, does not attract the attention of the patient. At this stage of the disease, the alveococcal node is small. Some patients have manifestations of allergy in the form of urticaria, sometimes with itchy skin.
Often, a patient or a doctor examining him accidentally, when palpating the liver, find a node of stony density in it, the surface of the organ is uneven, bumpy, and painless on palpation.
As the alveococcal node grows in the liver, the patient develops a number of subjective and objective symptoms of the disease: pain in the right hypochondrium, epigastrium, heaviness, bitterness in the mouth, nausea, belching, sometimes - weakness, urticaria, itching.
In the future, pain in the liver increases, periodically there are attacks of biliary-hepatic colic, dyspeptic symptoms intensify. A slightly painful "stone", "iron" liver is palpated.
At the stage of complications, obstructive jaundice develops more often than others, as well as purulent cholangitis. In this case, the patient develops a fever, chills, the liver rapidly increases in size, which becomes painful on palpation. Development of an abscess is possible.
When squeezing or sprouting the gates of the liver, in addition to ascites, jaundice, enlargement of the spleen, other symptoms of portal hypertension can be observed: dilation of the vessels of the abdominal wall, varicose veins of the esophagus and stomach, etc.
With the formation of decay cavities in the alveococcal nodes, the clinical picture changes: pain intensifies, the temperature rises, headaches, weakness appear. Although sometimes in patients, even in these severe cases, the condition remains satisfactory.
Alveococcosis is a disease that occurs all over the planet, regardless of the level of development of the country and the culture of nationalities. The disease causes special attention from doctors, alveococcosis occurs in 10 people out of 100 thousand, while the disease often leads to unpleasant consequences due to the complexity of treatment.
It is possible to get infected by eating unwashed berries, herbs that have been contaminated with the feces of various wild animals. In rare cases, eggs enter the human body through inhalation of dust.
Causative agent
Alveococcosis in the liver
Stages of the disease
During alveococcosis, several stages are distinguished:
Symptoms of alveococcosis
For a long time (from 5 to 15 years), alveococcosis in humans can proceed without symptoms, that is, imperceptibly. It is found during a preventive examination of a patient or during examination for other diseases, especially with an ultrasound examination of the liver (see photo).
- Sometimes the first sign of alveococcosis is jaundice caused by compression of the biliary tract. It is accompanied by yellowness of the mucous membranes, sclera, skin, itching, light feces, darkening of urine, signs of general intoxication.
- When examining a patient, it is possible to determine a significantly enlarged dense liver, painless, against the background of a completely normal patient's well-being. In such a patient, the doctor should find out whether he has lived for the past 15 years in areas with a high prevalence of alveococcosis, whether he has had contact with wild animals, or whether he has eaten unprocessed wild berries.
With a long course of the disease, there are complaints of heaviness in the right hypochondrium, weakness, lack of appetite, weight loss. The body temperature may rise slightly.
Effects
The most common complication of alveococcosis is obstructive jaundice, which occurs due to compression of the biliary tract. Others include:
Malignant alveococcosis with metastasis to the brain is especially severe.
Diagnostics
When examining patients with suspected alveococcosis, an epidemiological history is revealed (living in endemic zones, hunting, picking wild berries, processing skins and carcasses of wild animals, professional risks, etc.). Early stages are characterized by positive allergic tests (eosinophilia, Casoni's reaction with echinococcal antigen).
If alveococcosis is suspected, other focal liver lesions are excluded: tumors, hemangiomas, polycystic, cirrhosis, echinococcosis. To detect metastases, chest x-ray, MRI of the brain, ultrasound of the kidneys and adrenal glands, etc. are performed.
Alveococcosis treatment
When alveococcosis is detected in a person, the treatment regimen consists of three stages. At the first stage, the cyst is surgically removed. If it is localized in the liver, either the cyst itself is removed, or together with part of the organ. Complete resection is performed in only 15% of cases. If the brain is damaged, the operation can be performed in case of successful localization of the tumor. Sometimes it is not performed - if the cyst is located in a place where it is not possible to remove it. The same can be said about cases where the cyst is located in the lungs.
Prevention of such helminthiasis as alveococcosis consists in observing sanitary and hygienic requirements, taking measures to exterminate rodents capable of carrying helminths.
Forecast
The prognosis for alveococcosis is always serious. Without appropriate treatment, about 90% of patients die within 10 years. Lead to death:
- distant metastasis to the brain;
- infiltration of a tumor into neighboring organs with a violation of their functions;
- profuse bleeding;
- liver failure;
- purulent complications.
Surgical intervention leads to complete recovery, with early diagnosis and timely treatment, but the risk of incomplete removal of nodes and their further development is not excluded.
The causes of alveococcosis
Alveococcosis is caused by the larvae of the alveococcus tapeworm (Echinococcus multilocularis). The source of infestation is cats and dogs, as well as foxes and arctic foxes. Mature eggs are excreted in the faeces of these animals, contaminating their wool, environmental objects and soil. Human infection with alveococcosis occurs through contact with animals, as well as eating contaminated berries, vegetables and water.
Most often, for a long time, the disease proceeds without any visible manifestations. The clinical manifestations of alveococcosis directly depend on the size of the nodes, the rate of their growth and the presence of complications. At the initial stage, there are periodic aching pains and a feeling of heaviness in the right hypochondrium, decreased appetite and heartburn, nausea, vomiting. At the same time, the liver is enlarged, dense areas are felt. With the spread of nodes in the lungs, shortness of breath and cough, chest pains, hemoptysis are noted. Involvement in the pathological process of the kidneys is characterized by pulling pain in the lower back and urinary disorders, the appearance of blood in the urine. With the progression of alveococcosis, profound metabolic disorders and a sharp weight loss are observed, often fatal.
Possible complications of alveococcosis include portal hypertension and liver abscess, peritonitis and purulent cholangitis, pleurisy and pericarditis, chronic glomerulonephritis, etc.
Diagnostics of the alveococcosis
The diagnosis of alveococcosis is established on the basis of the clinical picture (nonspecific damage to various organs), in the presence of an epidemiological history (contact with infected animals), with the obligatory consideration of instrumental data of X-ray examination and radioisotope examination, ultrasound examination (ultrasound), computed and magnetic resonance imaging. In laboratory conditions, the disease is confirmed using the following specific methods:
- microscopic examination of sputum - detection of the causative agent of alveococcosis
- immunological research methods: reactions of enzyme-labeled antibodies with alveococcal diagnosticum, latex agglutination, indirect hemagglutination (RNGA), enzyme-linked immunosorbent assay (ELISA)
Non-specific methods of laboratory diagnosis of alveococcosis include a complete blood count (CBC) and a biochemical blood test. Differential diagnosis of alveococcosis is carried out with echinococcosis and polycystic liver disease, as well as cirrhosis and hemangioma.
Treatment and prevention of alveococcosis
The main directions of the prevention of alveococcosis are: careful observance of the rules of personal hygiene in contact with animals and housekeeping, prevention of infection of dogs, agricultural and hunting animals (deworming, keeping service dogs on a leash, strict adherence to the rules of their maintenance, determining the places for walking dogs , avoidance of vagrancy). Due to the high probability of infection, employees of fur farms, reserves and zoos, as well as tanners, hunters and persons engaged in catching dogs, are subject to periodic examinations for alveococcosis.
Alveococcosis (Echinococcus multilocularis) - helminthiasis, mainly affecting the liver. Its causative agent has an infiltrating growth, which causes metastases to different organs.
Alveococcosis is caused by the larvae of the alveococcus tapeworm (Echinococcus multilocularis). The source of infestation is cats and dogs, as well as foxes and arctic foxes. Mature eggs are excreted in the faeces of these animals, contaminating their wool, environmental objects and soil. Human infection with alveococcosis occurs through contact with animals, as well as eating contaminated berries, vegetables and water.
Epidemiology
Alveococcosis is widespread, more common in Central Europe, North America, and Asian countries.
Human infection occurs through contact with dogs and cats, with the skins of arctic foxes, foxes, wolves, etc. The final hosts (dogs, cats, wolves, arctic foxes, foxes) become infected by eating intermediate hosts (rodents) invaded by alveococcus larvae.
Germinating, and not pushing away the affected tissue, alveococcosis nodes cause circulatory disorders of the organ, degeneration and tissue atrophy. In addition to the mechanical effect, the larvae of the alveococcus also have a toxic and allergenic effect on the human body due to the entry of metabolic products into the blood and their decay.
Clinic, symptoms, course of alveococcosis
The disease develops gradually, unnoticed by the patient, slowly (over years and decades) and remains asymptomatic for a long time. Only the accidental detection of an enlarged liver by the patient himself or by the doctor makes him look for the cause of this first symptom. Often, patients turn to a specialist themselves, having found a tumor-like formation in the abdomen. With a further increase in the liver, the patient notes the severity and pressure in the right hypochondrium, then a dull and aching pain. After a few years, the palpable liver becomes bumpy and very dense. Jaundice may develop. In other cases, there is weakness, nausea, decreased appetite, dull, less often acute abdominal pain, progressive weight loss. Examination often reveals subicteric sclera, sometimes severe jaundice. The liver, as a rule, is enlarged, of "wooden" density, sometimes bumpy. Hyperproteinemia, hypergammaglobulinemia, hypalbuminemia are noted. Metastases to the lungs, brain, lymph nodes, heart, adrenal glands, kidneys, etc. are possible. Even metastases to the eye are possible.
The spleen is often enlarged. Sometimes ascites joins. In the presence of decay in the center of the nodes in advanced cases, there is a rise in temperature, loss of strength, sweating. Leukocytosis, eosinophilia appear, ESR is accelerated.
The formation of large necrosis and cavities in the nodes or invasion of the inferior vena cava can lead to profuse bleeding.
Diagnostics of the alveococcosis
The diagnosis of alveococcosis is established on the basis of the clinical picture (nonspecific damage to various organs), in the presence of an epidemiological history (contact with infected animals), with the obligatory consideration of instrumental data of X-ray examination and radioisotope examination, ultrasound examination (ultrasound), computed and magnetic resonance imaging.
In laboratory conditions, the disease is confirmed using the following specific methods:
- microscopic examination of sputum - detection of the causative agent of alveococcosis
- immunological research methods: reactions of enzyme-labeled antibodies with alveococcal diagnosticum, latex agglutination, indirect hemagglutination (RNGA), enzyme-linked immunosorbent assay (ELISA)
Non-specific methods of laboratory diagnosis of alveococcosis include a general blood test and a biochemical blood test. Differential diagnosis of alveococcosis is carried out with echinococcosis and polycystic liver disease, as well as cirrhosis and hemangioma.
Treatment
It is possible to perform a radical operation for liver alveococcosis only in 15-20% of patients. Most patients are admitted to surgery too late.
Early recognition makes it possible to completely remove the lesion.