Improved on-line thoracic duct drainage for lymphocytapheresis.

Lymphocytapheresis using thoracic duct drainage (TDD) is a recognized technique of extracorporeal immunomodulation for various autoimmune diseases such as rheumatoid arthritis (RA), and its clinical benefit has been reported and generally accepted. Lymphocytapheresis using TDD is very selective for removing lymphocytes (especially helper T-cells) but raises some problems such as hypoproteinemia due to the massive removal of lymph, and difficulties in repeated treatment. Along with the development of a new polyester fiber filter, we have developed a simple and effective method of lymphocytapheresis for wide adoption for these techniques. We performed lymphocytapheresis using TDD in patients with RA and previously reported its clinical efficacy indicated by the significantly lower number of peripheral lymphocytes and T4/T8 ratio. We present here our newly-developed on-line system designed to prevent hypoproteinemia. Furthermore we report on the advantages with a new subcutaneous vascular access device set up to manage the problems of repeated treatments. A small reservoir for keeping the thoracic duct open and returning lymph to the patient permitted sufficient lymph drainage and removal of lymphocytes and the clinical application of TDD is discussed.