A large pericardial cystic lymphangioma presenting as acute-onset respiratory distress in a child: a case report

BACKGROUND: Lymphangiomas are rare benign malformations of the lymphatics that occur due to blockage of the lymphatic system during fetal development. They commonly occur in the neck and axilla, while involvement of the pericardium is rare. We report herein the case of a 16-month-old Sri Lankan child with a large pericardial cystic lymphangioma presenting with sudden-onset shortness of breath. CASE PRESENTATION: A 16-month-old Sri Lankan boy presented with sudden-onset dyspnea for 1-day duration following a febrile illness that lasted 2 days. On examination, he was afebrile and had subcostal, intercostal, and suprasternal recessions, with a respiratory rate of 50 breaths per minute. He had a loud expiratory grunt. The chest expansion was reduced on the right side, which was dull to percussion. Auscultation revealed a marked reduction of air entry over the right lower and mid zones. Chest X-ray showed a well-demarcated opacity involving the lower and mid zones of the right hemithorax associated with a tracheal shift to the opposite side. Ultrasound scan of the chest revealed fluid-filled right hemithorax suggesting a septate pleural effusion. A contrast-enhanced computed tomography scan of the thorax showed a large multiloculated extrapulmonary cystic lesion involving the right hemithorax with a mediastinal shift towards the left side associated with displacement of the right-side mediastinal structures. He underwent mini-thoracotomy and surgical excision of the cyst. A large cyst originating from the pericardium was observed and excised during surgery. Histological examination revealed a lesion composed of cysts devoid of a lining epithelium but separated by connective tissue, mature adipose tissue, and lymphoid aggregates. The child showed complete recovery postoperatively with full expansion of the ipsilateral lung. CONCLUSION: We report the case of a patient with cystic lymphangioma who was perfectly well and asymptomatic until 16 months of age. This case report presents the very rare occurrence of a large cystic lymphangioma originating from the pericardium. It highlights the importance of considering rare possibilities and performing prompt imaging in situations of diagnostic uncertainty to arrive at an accurate diagnosis that can be lifesaving.