ABSTRACT
T herapeutic phlebotom y, therapeu tic apheresis and photopheresis all have in com m on the w ithdraw al (rem oval) o f b lood for therapeu tic purposes. The b lood is e ither discarded (therapeu tic phlebotom y); certain com ponents are rem oved and discarded; (therapeu tic apheresis), o r are subjected to processing ex vivo b e fore being re tu rn ed to the pa tien t (photopheresis). Thus, all these procedures are sim ilar in principle.
