Echinococcosis of the liver

Echinococcosis of the liver

Echinococcosis– helminthic invasion, proceeding with the development of echinococcal cysts in various organs. Etiology. The causative agent is a flatworm (cestode) Echinococcus granulosus of the Plathelminthes type. Epidemiology. Infection occurs when personal hygiene rules are not observed (eating food contaminated with parasite eggs or putting them into the mouth with dirty hands) and contact with sick animals. There are rural and hunting forms of the disease. The most common rural echinococcosis is recorded in Australia, New Zealand, Africa, USA, Central and South America, Europe and the Middle East. The main reservoir is dogs. Intermediate hosts – large and small cattle, sheep, camels, goats. Hunting (wild) echinococcosis is much less common, observed in Alaska and Canada, isolated cases are recorded in California and the North of Russia. The main host is the wolf, the intermediate hosts are rodents and reindeer. For all forms, man is a facultative intermediate host. Pathogenesis. When a person is infected, the oncospheres of the pathogen (eggs in a special shell) reach the duodenum, where they are released from the shells and with the help of hooks, pushing the cells of the mucous membrane, penetrate deep into the intestinal wall. Then, with the blood flow of the portal system, they are brought to the liver, where the majority settles in small capillaries. A smaller part bypasses the liver barrier and is deposited in the lungs or other organs. Under the influence of the body’s defenses, the larvae die in large numbers, and those that have penetrated into the organs begin to gradually grow, forming blisters (cysts) up to 10-20 cm in diameter. Echinococcal bladder has a double membrane, filled with a clear and colorless liquid, contains echinococcal sand (accumulations of scolex embryos) and often many child blisters. The latter reproduce asexually inside the mother’s bladder. Echinococcal cysts are prone to slow progressive growth and breakthrough into the liver parenchyma, bile ducts or free abdominal cavity. Before the onset of symptoms, the cyst grows for 10-20 years after the initial infection.

Clinical picture

• • Echinococcosis is often asymptomatic and is found only during a random examination. Echinococcal blisters often form in the liver (50-70%), lungs (20-30%), less often – in the brain or bones.
  • With echinococcosis of the liver, cysts are located in the right lobe. The earliest symptom: a feeling of heaviness and pain in the epigastrium and right hypochondrium. Suppuration of the bladder leads to the development of the clinical picture of a liver abscess. When opening an abscess, purulent pleurisy or peritonitis is possible. The breakthrough of an abscess into the bile ducts is the root cause of purulent cholangitis. The rupture of an uninfected bladder accompanies a complex of allergic reactions, up to the development of anaphylactic shock.
  • With echinococcosis of the lung, the echinococcal cyst is more often localized in the lower lobe of the right lung. Main symptoms: chest pain, cough, shortness of breath, sometimes hemoptysis.
  • With kidney echinococcosis, the clinical symptoms resemble hypernephroma.
  • When the cyst is localized in the brain, para- and hemiplegia, paresis and paralysis appear.
  • With invasion into bone tissues, pathological fractures are possible at the sites of parasite localization.

Research methods

• • X-ray examination
  • Ultrasound for echinococcosis of the abdominal cavity
  • Radioisotope scanning for suspected damage to the liver, spleen, kidneys
  • Serological tests (RSK, RIGA, RGA, ELISA) are positive in 60% of cases of lung damage and in 90% of cases of liver damage
  • If other diagnostic methods are not available, a puncture of echinococcal cysts is performed.

Treatment

• • Surgical removal of blisters
  • If surgical treatment is improbable, mebendazole 200 mg every 3 hours for 6 days.

Prevention. Timely detection and treatment of infected people. Periodic examination of dogs and their deworming.

Synonyms

• Echinococcosis hydatid
• Echinococcosis unicameral See also Alveococcosis ICD B67 Echinococcosis Literature. 129:308-310