Primary posterior mediastinal hydatid cyst is an exceptionally rare manifestation of hydatid disease, especially in the pediatric age group. Mediastinal localization accounts for only 0.1–4% of all hydatidosis cases, and presentation with acute respiratory distress in young children is even more uncommon. A 4-year-old boy from a rural, hydatid-endemic region presented to the emergency department with a two-week history of progressive dyspnea, dry cough, and fever, culminating in acute respiratory distress. Physical examination revealed tachypnea (48 breaths/min), intercostal retractions, decreased breath sounds over the right hemithorax, and tracheal deviation to the left. Chest X-ray demonstrated a large, well-defined homogeneous opacity occupying the right posterior mediastinum with compression of the trachea and right main bronchus. Contrast-enhanced computed tomography (CT) of the chest confirmed a 7.2 × 6.5 × 5.8 cm unilocular cystic lesion in the right posterior mediastinum with significant mass effect, but without evidence of pulmonary or hepatic involvement. The child underwent emergency right posterolateral thoracotomy with intraoperative isolation using povidone iodine-soaked gauze, controlled aspiration of cyst fluid, delivery of the germinative membrane, and pericystectomy. Postoperative histopathology confirmed a hydatid cyst with laminated membrane and protoscoleces. The patient received adjunctive albendazole (15 mg/kg/day in divided doses) for three 28-day cycles and remained recurrence-free at 12-month follow-up. Primary posterior mediastinal hydatid cyst is, although rare, should be included in the differential diagnosis of children of hydatid-endemic regions who develop acute respiratory distress.
Ashagre Gebremichael Ganta (Thu,) studied this question.