From the Guidelines
A hydatid cyst is a parasitic infection caused by the larval stage of the tapeworm Echinococcus, most commonly Echinococcus granulosus, which develops when humans accidentally ingest the parasite's eggs, typically through contact with infected dog feces or contaminated food and water. These cysts develop in various organs, with the liver being the most commonly affected (about 70% of cases), followed by the lungs (20%) 1. The cysts grow slowly, often taking years to cause symptoms, which depend on their size and location.
Key Characteristics of Hydatid Cysts
- They are caused by the larval stage of the Echinococcus tapeworm
- The liver is the most common site of infection, followed by the lungs
- Symptoms depend on the size and location of the cysts and can include cough, pleuritic pain, and breathlessness in the case of lung cysts
- Significant eosinophilia is uncommon except following cyst rupture 1
Treatment and Management
- Treatment typically involves surgical removal of the cyst, often combined with antiparasitic medications like albendazole (400mg twice daily for 1-3 months) 1
- Surgical removal is the primary treatment for most cases, with complete excision and conservation of as much lung tissue as feasible, accompanied by pre- and post-operative administration of praziquantel and albendazole 1
- Care must be taken during surgery to prevent cyst rupture, which could spread the infection or cause anaphylactic reactions
- Prevention involves good hygiene practices, especially handwashing after contact with dogs, and proper cooking of food in endemic areas, which include parts of Africa, South America, Eastern Europe, the Middle East, and Central Asia 1
From the Research
Definition of Hydatid Cyst
- A hydatid cyst, also known as Echinococcus cyst, is a parasitic infection caused by the Echinococcus tapeworm, primarily affecting the liver and lungs 2, 3, 4, 5, 6.
- The cysts are formed when the larval stage of the worm infects the human body, usually through ingestion of contaminated food or water 3, 6.
Characteristics and Symptoms
- Hydatid cysts can be asymptomatic, but symptoms may occur due to cyst expansion or host inflammatory reaction, including hepatomegaly, which is the most common sign 4.
- The cysts can cause complications such as infection, compression, or obstruction of adjacent organs, and may rupture, leading to life-threatening consequences 2, 3.
Diagnosis and Treatment
- Diagnosis is based on imaging modalities, such as ultrasound and tomography, and immunodiagnostics, including antibody detection 2, 4.
- Treatment options include medical therapy with albendazole, mebendazole, and praziquantel, surgical management, such as total pericystectomy or hepatectomy, and percutaneous treatment, including cyst evacuation and drainage 2, 3, 4, 5, 6.
- The choice of treatment depends on the size, location, and complexity of the cyst, as well as the patient's overall health and risk factors 3, 4, 5.