Successful Resection of Localized Intestinal Lymphangiectasia Post-Fontan: Role of 99mTechnetium-Dextran Scintigraphy

Abstract

Intestinal lymphangiectasia is a well-recognized complication of the Fontan procedure, occurring in up to 24% of patients. Because of the loss of chylous fluid into the gut lumen, protein-losing enteropathy results as well as lymphopenia and hypogammaglobulinaemia. In some cases, dilated lymphatics in the intestinal serosa or mesentery also rupture, causing chylous ascites. Standard medical and cardiac surgical interventions are generally ineffective and the condition is frequently lethal. We report a case of intractable and life-threatening chylous ascites and chylothorax in a 14-year-old girl, associated with intestinal lymphangiectasia and protein-losing enteropathy after a Fontan procedure for tricuspid atresia. The condition was refractory to all standard medical therapies, including dietary modifications, diuretics, corticosteroid therapy, albumin infusions, octreotide, heparin, bowel rest, and parenteral nutrition. Cardiac surgery to optimize her hemodynamic status was also ineffective and large volume pleural and ascitic fluid losses continued. Having exhausted all other therapeutic modalities, 99mtechnetium-dextran scintigraphy was performed to assess the extent of intestinal protein loss and the potential for surgical intervention. Scintigraphy suggested localized protein loss from the proximal jejunum and subsequent segmental resection was effective. Postoperatively, ascites and pleural effusions resolved, and there was no evidence of short bowel syndrome. Growth has accelerated and the patient has entered puberty. There is mild persistent intestinal protein loss requiring diuretic therapy. Ascites or pleural effusions are absent, and the patient remains well >2 years after surgery. Intestinal lymphangiectasia post-Fontan procedures has traditionally been ascribed to hemodynamic factors such as raised systemic venous pressure, which would predispose to a generalized intestinal lesion. However, in this case, scintigraphy demonstrated a localized, surgically correctible lesion. To our knowledge, this is the first reported case of the use of 99mtechnetium-dextran scintigraphy for this indication and of successful partial small bowel resection in such a case.