Echinococcosis

The disease that develops due to the introduction and growth in various organs of the larval bandworm - echinococcus. Its primary owner are dogs, wolves, jackals, foxes, etc. The parasite that lives in their lower intestine consists of the head, neck and segments - the most posterior and large, the fourth, is mature. Such a mature segment, separated from the worm, throws out eggs, which with feces stand out. More often the dog, being the carrier of helminth (worm), serves as a source of contamination by eggs of echinococcus pastures, reservoirs, premises for animals and human dwellings.
Since the swallowing of the joint or its eggs (the so-called oncosphere), the period of development of the parasite larva begins. Digestive juices help the embryo to get rid of the membranes and with the help of its hooks penetrate into the mucous membrane of the gastrointestinal tract. Further, with a current of blood or lymph, spreads to the organs (liver, lungs, kidneys, muscles) and, already settling in their tissues, turns into a larva. By the end of 2 weeks it takes a bubble structure.
After 5 months. The formed bubble has a diameter of 5 mm. Later the bubble grows slowly, over the years, and gradually, after 20-25 years, reaches a large size, with a capacity of 10 liters or more: a connecting capsule with walls of chitin. The cavity of this cyst is filled with a slightly yellowish neutral reaction liquid containing sodium chloride, grape sugar, tyrosine, succinic acid, albumin, etc. The chitinous membrane consists of two layers: an outer dense (cuticular) thickness of up to 0.5 cm and an internal (germinal) embryonic , From which are formed in large numbers, sometimes up to 1000, daughter blisters.
Pathological changes in the human body are associated with mechanical pressure on the organs of a growing cyst. The products of the vital activity of the parasite irritate surrounding tissues, causing their chronic inflammation.
There are four stages of echinococcosis: the first - latent, from the moment of invasion of the oncosphere (penetration into the body) until the appearance of subjective symptoms; The second - weakly expressed, mainly subjective disorders; The third - sharply expressed objective symptoms and the fourth - complications. The duration of the course of the stages, given the slow growth of the echinococcal cyst, is difficult to establish. It can only be noted that the rapidity of the increase in symptoms is associated with the localization of echinococcus. For example, a cyst that develops in the peripheral parts of the liver parenchyma can not give many sensations for many years; if it develops near the gates of the liver, squeezing the hepatic passages causes obstructive jaundice rather quickly, and squeezing the portal vein leads to the development of ascites .
Clinical manifestations at the initial stages of the disease are usually scarce, they are detected when the cyst reaches a considerable size or in connection with its location will squeeze an important organ and lead to a disruption of its function. Echinococcal cyst of internal organs (liver, kidneys, spleen, etc.) is usually recognized when a tauto-elastic tumor is probed, and lung and bone lesions are determined on the x-ray images in the form of cystic formations.
Important common symptoms of echinococcosis are the periodically developing signs of an allergic reaction (urticaria, etc.), which is usually associated with the absorption of echinococcal fluid during tearing of the cyst shell or as a result of surgery. For echinococcosis, as, indeed, for other helminthic diseases, eosinophilia is typical, reaching 10-25%.
A specific laboratory reaction is the reaction of Casoni, which is positive in cases of echinococcus infection in 89-90% of cases. The technique of producing the Casoni reaction is as follows: 0.2 ml of sterile echinococcal fluid is administered intradermally. With a positive reaction at the injection site, redness appears, followed by a continuous intense redness (cutaneous anaphylaxis).
Dangerous complications of the echinococcal cyst are suppuration or rupture of it with contamination of the abdominal, pleural or any other cavity.
Diagnosis of echinococcosis often presents significant difficulties. In recent years, in addition to general clinical methods of research, contrast methods have become more widely used, for example, transumbilical portogepathography, selective angiography of the celiac artery, scanning with radioactive isotopes, which help diagnose liver echinococcosis, computed tomography.
The extraction of echinococcus is possible only in an operative way. There are several methods of operation:
1) radical echinococcectomy, i.e. Complete removal of the echinococcal cyst along with its fibrous membrane, 2) opening of the cyst with removal of fluid, all daughter blisters and chitinous membrane with wiping the formed cavity with a disinfecting solution of formalin and plugging, draining or sewing it tightly.
When the echinococcal cyst is opened, special attention is paid to the isolation of body cavities and tissues from the echinococcal fluid, since its entry into the cavity (abdominal, thoracic, etc.) or to the walls of the wound can lead to contamination.
It is determined by the correct organization of sanitary control in slaughterhouses. The exclusion of the possibility of using the organs of animals affected by echinococcus or feeding them to dogs. Veterinary supervision of dogs, especially for domestic animals, is of great importance, and when keeping and communicating with them, the strictest observance of the rules of personal hygiene.