Mediastinal Hydatic cyst:a rare entity

<bold>Introduction:</bold> Mediastinal hydatid cysts account for 4% of all mediastinal masses in endemic countries. They are the prerogative of young adults, without gender predominance. Hydatid involvement of the posterior mediastinum is isolated in the majority of published cases. An association with cardiac involvement is found in 33% of cases. Surgery provides diagnostic confirmation in contentious cases, and is the curative treatment for hydatidosis. <bold>Material and methods:</bold> This is a retrospective study conducted between 2002 and 2023 in the Department of Thoracic Surgery of the Abderrahmane Mami Hospital on patients who had been managed for primary hydatidosis of the posterior mediastinum. <bold>Results:</bold> our study included 6 women and 2 men. The patients had no particular medical or surgical history. The mean age was 34.2 (range 23-40). Symptoms included chest pain in 100%, exertional dyspnea in 60% and hemoptysis in 20% of cases. All cysts were located on the left and were uncomplicated. No other intra- or extra-thoracic hydatid localization were noticed in all patients. The approach was a left posterolateral thoracotomy in 100% of cases. Cystectomy was performed after opening the cyst in 62% (5/8) of patients. In 38% (3/8) of cases, total pericystomy with closed cyst was performed. The post-operative follow-up was straightforward in all cases. There were no postoperative complications or mortality. No recurrence was observed during postoperative follow-up. <bold>Conclusion:</bold> Mediastinal localization of KH is rare. This location often poses a delicate diagnostic problem with cystic lesions of the mediastinum. The radical treatment is surgery, the post-treatment evolution is often favorable. Early management prevents complications.