Gastrointestinal: Focal lymphangiectasia

Abstract

What disorders of the gastrointestinal tract are associated with pathological changes in lymphatic vessels? Perhaps the best known is that of intestinal lymphangiectasia. This can occur as a primary congenital disorder (Milroy’s disease) or may be secondary to widespread lymphatic obstruction from disorders such as retroperitoneal carcinoma or lymphoma, retroperitoneal fibrosis, constrictive pericarditis and chronic congestive cardiac failure. The presenting symptoms are those of intestinal malabsorption and protein-losing enteropathy. At duodenal endoscopy, dilated lacteals can be seen as diffuse white spots or white-tipped villi sometimes associated with white nodular lesions. The histological appearance is that of marked dilatation of lacteals, sometimes associated with mucosal inflammation and blunting of villi. Rare disorders of the lymphatic system include cavernous lymphangiomas and lymphangiomyomatosis. Cavernous lymphangiomas are usually diagnosed early in life and are thought to be a developmental abnormality of lymphatic vessels. In the abdomen, the most common sites for cavernous lymphangiomas are the mesentery and retroperitoneum. In lymphangiomyomatosis, there is diffuse proliferation of smooth muscle within lymphatics and lymph nodes in the retroperitoneum and mediastinum. This may also involve lung parenchyma. Another disorder of lymphatic vessels is a localized form of intestinal lymphangiectasia as illustrated below. The patient was a women, aged 29, who was investigated because of intermittent epigastric pain for several months. Various blood tests including a lymphocyte count were within the reference range. Endoscopy revealed an elevated whitish plaque, about 2 cm in diameter, in the second part of the duodenum. In addition, there were several other white spots in the region (Fig. 1). After a biopsy was taken, milky fluid drained into the duodenal lumen. Histological evaluation revealed marked dilatation of lymph vessels in the mucosa and submucosa without any evidence of inflammation (H&E ×40) (Fig. 2). This example of focal lymphangiectasia was attributed to a localized developmental abnormality of lymphatic vessels that involved the second part of the duodenum.