Chapter 483 Abnormalities of Lymphatic Vessels
Abnormalities of the lymph vessels may be congenital or acquired. Signs and symptoms result from increased lymphatic tissue mass or from leakage of lymph. Lymphangiectasia is dilation of the lymphatics. Pulmonary lymphangiectasia causes respiratory distress (Chapter 387.6). Involvement of the intestinal lymphatics causes hypoproteinemia and lymphocytopenia secondary to loss of lymph into the intestines (Chapter 330). Therapy includes minimizing the hydrostatic pressure in the lymphatic system, leading to decreased protein loss. Reducing dietary intake of long chain fatty acids and substituting medium chain triglycerides via formula accomplishes this goal. Lymphangioma is a congenital lymphatic malformation, usually detected by the age of 2 yr. Lymphangioma circumscriptum is defined as the presence of many small, superficial lymphangiomas. Deeper lymphangiomas are classified as either cavernous lymphangiomas or cystic hygromas. Lymphangiomatosis is the presence of multiple or disseminated malformations. Some of these lesions also have a hemangiomatous component (Chapter 499