Congenital abnormalities of the lymphatic system: a new clinical classification. The numerous clinical presentations of congenital abnormalities of the lymphatic system in children and the confusing terminology used to describe their pathologic diagnoses impede the physician's understanding of the condition. The clinical classification based on the actual symptoms of the congenital problems we have presented here should help the physician identify the specific abnormality and a potential treatment. Future research should concentrate on the specific causes and the treatment of these congenital abnormalities. 