A rare and challenging case of intrapericardial hydatidosis

BACKGROUND: Hydatid cysts are most frequently located in the liver and lungs and very rarely can be found in the pericardium. Diagnosis and treatment are quite challenging, as the disease can present itself in many forms depending to the location and the complications that it might cause. CASE PRESENTATION: A 22-year-old man presented to our hospital with ongoing dry cough for more than 1 month prior to admission. Other symptoms included chest pain, fatigue, low grade fever, and night sweats, which have worsened in the past 2 weeks. Physical examination revealed normal respiratory and heart function. Chest X-ray demonstrated mediastinal enlargement and left pleural effusion. Contrast-enhanced computed tomography images showed a walled cystic mass lesion measuring up to 56 × 50 mm in close proximity to the upper left atrium, ascending aorta and pulmonary artery, potentially localized in the pericardium, with a 10 mm endoatrial filling defect, findings were compatible with hydatid cyst, left pleural effusion and peripheral pulmonary upper left lobe consolidation. Cardiac involvement was excluded on magnetic resonance imaging and trans-esophageal ultrasound. The patient underwent fine needle aspiration of the affected lung and thoracocentesis. No malignancy was found, meanwhile the biopsy confirmed the presence of pulmonary infarction. In view of the imaging findings were highly suspicious of a hydatid cyst, we performed a test of antibody titers that was negative. The patient underwent left anterolateral thoracotomy, and after the opening of the pericardium, a cystic mass of 5 cm in diameter was found next to the left atrium and in close proximity with the left pulmonary veins. The content of the cyst was completely removed after the surgical area was isolated with gauze impregnated with hypertonic solution (NaCl 10%). The mass resulted to be an echinococcal cyst with multiple daughter cysts within it that did not penetrate/involve (perforate) the cardiac wall. CONCLUSION: Pericardial echinococcosis is a very rare pathology in which a high expertise multidisciplinary approach is required. The compression mass effect caused by the cyst can lead to complications, such as in our case where the pulmonary vein was compressed, leading to pulmonary infarction. The value of radiology studies and transoesophageal ultrasound are very important in the diagnosis. Surgery in these cases is always recommended, but preferred surgical approach is questionable. In cases such as ours, we recommend anterolateral thoracotomy.