Cystic Lymphangioma: Are Triglycerides Always Measurable?

The presence of chylous fluid with high triglycerides levels on endoscopic ultrasound- (EUS-) guided fine needle aspiration (FNA) is very pathognomonic for the diagnosis of cystic lymphangiomas of the pancreas. In our case report the puncture of the pancreatic cyst showed a typical milky fluid though measurable triglyceride concentrations were absent in the laboratory. Two possible explanations were found. First of all grossly lipemic samples show a slower rate of color development than do clear serums which can produce a false negative result if the sample is insufficiently diluted. Secondly, high lipase levels can divide triglycerides in glycerol and fatty acids, making the concentration of triglycerides undetectable.