Lung Hydatid Cyst
Etiopathogenesis, Evolution, Diagnosis, Therapy.
It is a disease caused by the localization and development in the lung of the Taenia Echinococcus larva.
The parasite eggs removed from the dog's intestine (the definitive host) infest the intermediate host (people). Contamination occurs either directly through repeated contact with the dog, through dirty hands, or indirectly through water or infested food.
The cyst is made up of a membrane called proliferation or germinative, which gives birth to daughter vesicles and a clear liquid. Cysts may be single or multiple, the most common being located at the base of the right lung.
This disease evolves in three phases.
- The first phase is a closed cyst and is characterized by usually negative clinical signs. Occasionally itching, pruritus, irritable cough, dyspnoea or hemoptysis may occur. The radiological examination reveals a rounded opacity with a boundary contour. Upon diagnosis, the blood pressure is greater than 5%, the Casoni intradermodality positivity and the complement fixation reaction.
- The second phase is characterized by opening into a bronchus, which removes a clear salty liquid, possibly membranes. It is accompanied by coughing, dyspnea and violent pain, sometimes hemoptysis. Anaphylactic phenomena occur frequently.
- The infected cyst phase, the last phase, carries out the symptoms of pulmonary suppuration.
Evolution is slow, with phenomenal compression (cyanosis, dyspnoea, cough) that occurs when the cyst has reached the volume of an orange (possibly in 2-3 months, but also 3-4). Sometimes it can perforate in the bronchi, in the pleural cavity.
The diagnosis of the disease is based on anamnesis (animal contact, urticaria), radiological image, blood eosinophilia, and Casoni intradermosis.
Radical lung hydatid cyst treatment is surgical. Disease prophylaxis aims at avoiding intimate contact with dogs, systematic washing of hands before eating and also washing the fruits and vegetables that can be infested with dog manure. An infected cyst is treated as a lung abscess.