Primary heterotopic pleural hydatidosis: a rare entity

Abstract

Introduction: Primary heterotopic pleural hydatidosis, defined by the growth of an intact hydatid delivered from the lung to the pleural cavity after the isolated rupture of its pericyst, is an exceptional entity.

Methods: We report 3 cases of heterotopic pleural hydatid cyst operated in our surgical department from 2004 to 2020, revealed by a pneumothorax.

Results: They were 3 female patients. the average age was 30.66 years. Symptomatology was made of dyspnea and acute chest pain related to pneumothorax in 2 cases, and hydropneumothorax in 1 case. They had and anterior thoracic drainage, which partially brought the lung back to the chest wall. A chest CT scan was done in 2 cases showing a collapse of the left basal lobe with a cystic intra pleural formation of 11cm in one case, and a collaps of the middle and lower lobe with a fluid pleural formation of 20cm suggesting a hydatid cyst in the 2 nd case. The 3 rd patient was pregnant and had a chest ultrasound reveling a large cystic formation measuring 14cm associated with a low abundance of hydro-aeric pleural effusion. All patients were operated by a posterolateral thoracotomy. An extraction of the intact hydatid was performed in 2 cases associated with treatment of the residual cavity. For the other case, given the large size of the hydatid, the extraction of the vesicle was done after emptying its contents. The postoperative course was uneventful in all cases. After surgery, all patients were treated by 3 months course with Albendazole, with a favorable outcome.

Conclusion: Primary heterotopic pleural hydatidosis is an extremely rare entity even in highly endemic countries. The lack of clinical and radiological specificities makes this pathology often difficult to diagnose and treat.