A newborn girl with family history of lymphedema is noted to have bilateral lower extremity swelling. What is the diagnosis?

Lymphedema is classified by etiology - primary versus secondary. Primary lymphedema is divided into congenital, praecox, and tarda, depending on the age of onset. The diagnosis of Milroy disease is reserved for patients with familial lymphedema in which clinical factors are present at birth or noticed soon thereafter. Lymphedema is classified as praecox if the age of onset is between 1 and 35 years. Meigs' disease is the familial form of primary lymphedema praecox. If the onset of primary lymphedema is after 35 years of age, it is called lymphedema tarda. Secondary lymphedema usually results from a disease process that causes obstruction of the lymphatic system.