Primary intestinal lymphangiectasia (PIL) or Waldmann's disease is a rare 
protein-losing gastroenteropathy of unknown etiology. Less than 200 cases have 
been reported globally. Patients may be asymptomatic or present edema, 
lymphedema, diarrhea, ascites and other manifestations. We report two pediatric 
cases with PIL with extremely different outcome in a 3-year follow-up period. 
The first patient presented with persistent diarrhea, hypoalbuminemia and 
failure to thrive, while the second patient presented with an abrupt eyelid 
edema. Hypoproteinemia was the common laboratory finding for the two patients 
and upper gastrointestinal endoscopy established the diagnosis. The first 
patient relapsed five times during the follow-up period after the diagnosis had 
been made and required intravenous albumin administration and micronutrient 
supplementation. The second patient revealed normal gastrointestinal endoscopy 4 
months after the diagnosis had been established; he followed an unrestricted 
diet and remained asymptomatic throughout the follow-up period. PIL can be 
either severe, affecting the entire small bowel, leading to lifetime disease, or 
sometimes affects part of the small bowel, leading to transient disorder.