Chylous Bronchial Casts After Fontan Operation

A 4-year old boy with D-transposition of the great arteries, pulmonary atresia with intact ventricular septum, and a hypoplastic left ventricle with mitral atresia underwent a Fontan operation.He had previously been treated with neonatal balloon atrial septostomy followed by a left modified Blalock-Taussig shunt and, at the age of 2 years, a Hemi-Fontan operation was performed.The Fontan operation was completed with an extracardiac conduit (Goretex) from the inferior vena cava to the superior vena cava.High central venous pressures and bilateral chylothoraces complicated the postoperative course.Despite 6 weeks of conservative treatment with fat-free nutrition and subsequent total parenteral nutrition, pleural fluid loss remained excessive, and a pleurodesis was performed bilaterally.A few days postoperatively, acute respiratory failure occurred due to bronchial casts.Cast analysis showed high triglyceride and protein concentrations (cast triglyceride, 0.96 mmol/L; cast protein, 66 g/L; serum triglyceride, 0.36 mmol/L; and serum protein, 47 g/L).Bronchoscopic attempts to remove the bronchial casts failed, and the child died of cardiorespiratory failure.At autopsy, the bronchial system was completely plugged by casts resembling bronchial tree anatomy (Figure 1).Thromboses obliterated the left innominate vein partially and reduced the lumen of the extracardiac conduit by 50%.These