Interventional embolization for hemorrhagic pleural effusion in an infant with kaposiform lymphangiomatosis: a case report.

Background: Kaposiform lymphangiomatosis (KLA) is a rare, aggressive lymphatic anomaly that frequently involves the thorax and may be complicated by hemorrhagic pleural or pericardial effusion, thrombocytopenia, and coagulopathy. Acute respiratory compromise in infancy is uncommon and can be difficult to manage because surgery is often limited by infiltrative disease and bleeding risk. Case presentation: A two-month-old male infant presented with a four-day history of progressive respiratory distress and reduced milk intake. Physical examination showed tachypnea and decreased breath sounds over the left hemithorax. Laboratory tests demonstrated anemia and thrombocytopenia. Contrast-enhanced computed tomography angiography revealed a large left pleural effusion with mediastinal shift, left lung atelectasis, and tortuous dilated vascular structures involving the left pericardium, diaphragm, and anterior thoracic wall. Emergency closed thoracic drainage yielded hemorrhagic pleural fluid. Angiography identified hypervascular lesions supplied by branches of the left internal thoracic artery and left phrenic artery, with active contrast extravasation from the phrenic arterial supply. Superselective embolization was performed using polyvinyl alcohol particles and gelatin sponge, followed by systemic methylprednisolone and sirolimus. Outcome: Drainage output became clear after embolization. Six-month follow-up magnetic resonance imaging showed near-complete resolution of the lesion. During 5 years of follow-up, the platelet count remained above 100 × 10 Conclusion: In selected patients with KLA and hemorrhagic pleural effusion, angiography can clarify the bleeding source and superselective arterial embolization may provide rapid hemorrhage control and respiratory stabilization, serving as a valuable adjunct to systemic therapy.