Therapeutic cytapheresis: too many platelets, too many white blood cells.

Myeloproliferative disorders may present with thrombocytosis and/or leukocytosis with symptoms ranging from minor to life-threatening. Therapeutic cytapheresis (TC), the removal of excess and/or abnormal cells such as platelets and white blood cells, can be used to rapidly reduce cells in the symptomatic patient. The patient's clinical status determines the need for TC as symptoms may not correlate to laboratory values. TC does not alter the underlying disease process but serves as a bridge until drug therapy is initiated. Because of low frequency of procedures performed and the often urgent need for treatment, clinical data for the use of TC are difficult to collect and analyze. American Society for Apheresis Clinical Applications Committee has described indications for TC for treatment of disease entities. These publications provide guidelines for these less commonly performed procedures. Maintaining staff education, competency, and proficiency for these urgent procedures is an ongoing challenge for the majority of therapeutic apheresis programs.