Congenital Pulmonary Lymphangiectasia Associated With Congenital Heart Disease
Two cases of rare congenital pulmonary lymphangiectasia (CPL) associated with congenital heart disease (CHD) were diagnosed during one year period. Both patients presented in the neonatal period with respiratory distress, radiologic findings of interstitial pulmonary edema and later development of bilateral chylothoraces and chronic respiratory failure. The condition is usually lethal.
Case #1: A full term male with uncomplicated prenatal course, presented with progressive respiratory distress and cyanosis after birth, requiring high oxygen intubation and mechanical ventilation. He was hemodynamically stable, but had an active precordium with grade 2/6 systolic murmur at left sternal border and coarse breath sounds bilaterally. Chest x-ray showed increased vascular markings without cardiomegaly. Echocardiography showed possible cor triatriatum with patent ductus arteriosus (PDA), atrial septal defect (ASD) associated with right ventricular hypertrophy and pulmonary hypertension. Prostaglandins were started. He underwent corrective surgery and was found to have an anomalous connection of the pulmonary vein confluence to coronary sinus, that was repaired and communication between pulmonary vein and left atrium was established. ASD was repaired and PDA ligated. He had multiple failed extubation attempts secondary to pulmonary edema, interstitial lung disease and bilateral recurrent pleural effusion/chylothoraces despite thoracic duct ligation and discontinuation of enteral feeds. He received steroids for chronic lung disease without improvement. Cardiac catheterization showed no pulmonary vein obstruction or intracardiac shunts. Lung biopsy done at two months of life showed CPL. Support was withdrawn and the patient died.
Case #2: A full term female with uncomplicated prenatal course, presented with cyanosis and respiratory distress seven hours after birth, requiring intubation and mechanical ventilation. She was hemodynamically stable, but had grade 2/6 systolic murmur. Echocardiography showed dextrocardia, transposition of great arteries, ASD, patent ductus and pulmonary arteries, pulmonary atresia, nearly absent interventricular septum with essentially single ventricle anatomy. Chest x-ray showed dextrocardia, small heart and increased interstitial markings bilaterally. She was started on prostaglandins and dopamine. She developed abdominal distension, oliguria, acidosis, elevated blood urea nitrogen and creatinine. Necrotizing enterocolitis was ruled out as well as renal anomaly. She underwent aortopulmonary shunt placement and peritoneal dialysis. She had persistent interstitial pulmonary edema and developed bilateral chylothoraces. She had multiple failed extubation attempts. She received prolonged steroids for chronic lung disease without improvement. Echocardiography showed no pulmonary venous obstruction. Lung biopsy done at one month of life showed CPL. The patient died at 2 months age.
CPL associated with CHD is rare. We present 2 patients with similar presentation at birth, but with two different types-of congenital heart anomalies. Both cases were associated with pulmonary arterial hypertension, but no pulmonary venous obstruction. Both cases were complicated by persistent chylothoraces postoperatively. Differential diagnoses include systemic venous obstruction/systemic venous hypertension and intraoperative damage to the lymphatic vessels. Case #1 was associated with thrombosis and partial occlusion of both internal jugular and brachiocephalic veins, but no obstruction of superior or inferior vena cava. In both cases, lung histopathologic studies showed dilated lymphatics in pleura and interstitial vascular channels, consistent with pulmonary lymphangiectasia. CPL was confirmed with immunoperoxidase and triehrome stains. Presence of smooth muscles in intra-acinar arteries was consistent with pulmonary hypertension. It is generally accepted that CPL is associated with pulmonary venous obstruction, but there was no such association in our patients. This suggests the possibility of a primary defect in the development of pulmonary lymphatics in the pathogenesis of CPL.
High index of suspicion for CPL is required in children with CHD presenting with severe respiratory distress on the first day of life with radiologic findings of diffuse interstitial pulmonary edema, and progressively worsening respiratory failure associated with persistent chylothoraces. Lung biopsy is diagnostic and should be considered early. More studies are needed before effective palliation or definite therapy for this often lethal condition can be developed.