Abstract
Hydatid disease is a parasitic infection caused by Echinococcus species. Mediastinal involvement is rare, especially in children. We report a case of a four-year and eight-month-old girl who presented with progressive shortness of breath, cyanosis, and weight loss over two months. Imaging revealed a large cystic lesion in the middle mediastinum, compressing the trachea and superior vena cava. Surgical excision confirmed a hydatid cyst, and postoperatively, the patient received antihelmintic therapy with a favorable recovery. Mediastinal hydatid cysts are rare but should be considered in endemic areas. Early diagnosis and surgical intervention are crucial for optimal outcomes.