Alveokokkoz - the parasitic disease caused by larvae of tape helminth of an alveokokk and proceeding with formation of primary center in a liver. In an uncomplicated stage of manifestation of an alveokokkoz include urticaria, a skin itch, a gepatomegaliya, weight and pain in the right podreberye, bitterness in a mouth, an eructation, nausea. As complications of an alveokokkoz suppuration of a parasitic tumor, break of education in belly or pleural cavities, mechanical jaundice, portal hypertensia, metastasis of an alveokokk in a brain and lungs can act. For diagnostics of an alveokokkoz ultrasonography and a stsintigrafiya of a liver, an angiography, X-ray analysis/KT of an abdominal cavity and a thorax is used. Surgical treatment of an alveokokkoz is supplemented with antiparasitic therapy.
Alveokokkoz (alveolar or multichamber echinococcosis) – as which activator the larval stage of the Alveococcus multilocularis helminth causing opukholevidny damage of a liver with the subsequent infiltrative growth or metastasis in lungs, a brain and other bodies acts. Alveokokkoz of the person is among seldom found natural and focal helminthoses, incidence of which in endemic areas makes 0,01-0,08%. Cases of an alveokokkoz meet in Canada, the USA, Europe (Germany, Austria, France, Switzerland), Asia, Russia (Yakutia, Kamchatka, Chukotka, Western Siberia, the Volga region). The persons of young and middle age, mainly, who are engaged in hunting catch Alveokokkoz more often.
Reasons of an alveokokkoz
For the person danger is constituted by a larval stage of the Alveococcus multilocularis helminth relating to flat worms of a subfamily of Echinococcine. Polovozrely forms of an alveokokk on a structure are close to an ekhinokokk, however differ in quantity on a skoleksa (usually 28–32 pieces), lack of side branches in a uterus, an arrangement of a sexual opening in a forward part of a chlenik. The main difference of parasites consists in a structure Finns which at an alveokokk has the form of the grozdyevidny bubbles filled with jellylike weight. Affiliated bubbles are formed by budding and grow outside, but not inside, as at an ekhinokokk.
The adult has the sizes of 1,6-4 mm, consists of a head with 4 suckers and kryuchyam, 2-3 chlenik. In the last chlenik the spherical uterus containing about 400 eggs settles down. Tape helminth parasitizes in intestines of a polar fox, wolf, fox, dog, cat who are the main owners of an alveokokk. Mature eggs with excrements of animals are allocated to the environment from where get to an organism of intermediate owners (mice, muskrats, river beans, nutrias and the person) where larval development of a parasite proceeds. Infection of the person alveokokkozy can occur when entering in a mouth an onkosfer of helminth during hunting, cutting of carcasses of wild animals, removal and processing of skins, contact with pets, consumption of the wild berries and herbs polluted by helminth eggs.
In a human body the larva of an alveokokk leaves egg and with a blood-groove is brought in a liver where is almost always late. Primary other bodies meets extremely seldom. In a liver the larva is transformed to a bubble with a diameter of 2-4 mm which begins to breed by exogenous budding. Gradually in soyedinitelnotkanny Strom of a liver the dense, melkobugristy parasitic tumor with a diameter from 0,5 to 30 cm and more is formed. On a section the knot of an alveokokk has an appearance of the porous cheese (or porous fresh bread) consisting of a large number of chitinous bubbles. Similarly malignant tumor, the parasitic knot is capable to sprout in surrounding fabrics and bodies (epiploons, a diaphragm, a pancreas, the right kidney, an adrenal gland, a lung, etc.), lymphatic ways and blood vessels, extending with blood current on an organism and forming the remote metastasises, most often in a brain.
Symptoms of an alveokokkoz
In development of an alveokokkoz allocate the asymptomatic, uncomplicated and complicated stages. Character of a course of alveolar echinococcosis can be slowly progressing, actively progressing and malignant. The preclinical stage of an alveokokkoz can last for many years (5-10 years and more). At this time patients are disturbed by urticaria and a skin itch. Identification of an alveokokkoz during this period usually happens to the help of the ultrasonography which is carried out concerning other disease. In an early manifest stage symptoms of an alveokokkoz of a malospetsifichna, include a gepatomegaliya, weight and dull aches in the right podreberye, pressure in epigastriya, bitterness in a mouth, nausea. At survey increase and asymmetry of a stomach quite often is found; at a palpation of a liver the dense knot decides on an uneven hilly surface. Patients feel weakness, deterioration in appetite, weight loss. At an alveokokkoza periodic attacks of hepatic colic, the dispepsichesky phenomena are possible.
As the most frequent complication of an alveokokkoz serves the mechanical jaundice caused by a compression of bilious ways. In case of accession of a bacterial infection liver abscess can develop that is followed by strengthening of pains in the right podreberye, emergence of gektichesky fever, oznob, pouring sweats. At break of a parasitic cavity purulent can develop holangit, peritonitis, an empiyema of a pleura, perikardit, plevropechenochny and bronkhopechenochny fistulas, aspiration pneumonia. In case of a sdavleniye the portal hypertensia which is followed by a gullet varicosity, esophageal and gastric bleedings, a splenomegaliya, ascites arises a tumoral conglomerate of gate of a liver. At interest of kidneys the proteinuria, a gematuriya, a piuriya develops, the infection of urinary tract joins. As a consequence of immunopathological processes serves formation of a chronic glomerulonefrit, amiloidoz and a chronic renal failure.
Metastasis of an alveokokk most often occurs in a brain; in this case there are focal and all-brain symptoms (dzheksonovsky attacks, mono - and a hemiparesis, dizzinesses, headaches, vomiting). The heavy and transient current of an alveokokkoz is observed at patients with an immunodeficiency, the pregnant women, persons having serious associated diseases. Quite often alveolar echinococcosis comes to an end letalno.
Diagnostics and treatment of an alveokokkoz
At inspection of patients with suspicion on the epidemiological anamnesis becomes clear (accommodation in endemic zones, occupation hunting, gathering wild-growing berries, processing of skins and carcasses of wild animals, professional risks and so forth). Positive allergic tests are characteristic of early stages (an eozinofiliya, Kazoni's reaction with an ekhinokokkovy anti-gene). Specific methods of laboratory diagnostics of an alveokokkoz include immunological reactions (RIGA, RLA, IFA), PTsR. For detection of alveolar echinococcosis of a liver, size and an arrangement of parasitic knot the survey X-ray analysis of an abdominal cavity, ultrasonography and doppler sonography of a liver is used. A noninvasive alternative of arteriography and a splenoportografiya is the computer tomography. In difficult situations the liver stsintigrafiya, a diagnostic laparoscopy is used.
At suspicion on other focal damages of a liver are excluded: tumors, gemangioma, , cirrhosis, echinococcosis. For identification of metastasises the X-ray analysis of a thorax, MRT of a brain, ultrasonography of kidneys and adrenal glands etc. is carried out.
At an alveokokkoza of a liver the surgical treatment added with antiparasitic therapy is shown. Most often as operation of the choice serves the liver resection within healthy fabrics (a segmentektomiya, lobectomy), however radical removal of a parasitic tumor is possible only in 15-25% of cases. At impossibility of radical excision of knot its partial resection or a vylushchivaniye with the subsequent infiltration by chemotherapeutic medicines (solution of a tripaflavin, formalin) or destruction of parasitic fabric by means of cryoinfluence is made. Operation of a marsupialization of a parasitic cavity, stenting of bile-excreting channels is in some cases used. System antiparasitic therapy of an alveokokkoz is performed levamizoly, mebendazoly.
Forecast and prevention of an alveokokkoz
Slow and asymptomatic development of a parasitic tumor leads to what in most cases is diagnosed late that often does not allow to carry out radical treatment. The forecast at alveolar echinococcosis rather serious: without treatment 10-year survival does not exceed 10-20%. Death of patients occurs owing to purulent complications, a liver failure, profuzny bleeding, germination of a tumor in nearby bodies with violation of their functions, the remote metastasis in a brain, etc.
Prevention of an alveokokkoz comes down to carrying out expulsion of helminths of pets, veterinary supervision, observance of precautionary measures at interaction with wild animals, sanitary and educational work with the population of endemic areas. The persons which are put the increased professional risk of infection alveokokkozy (shepherds, hunters, workers of fur farms, etc.), are subject to regular screening inspection.