Granulocytapheresis – Technique & Its Importance

The granulocyte infusion is a lifesaving procedure when intervened at an appropriate time. Typical candidates for granulocyte transfusions are prolonged neutropenic patients ( ANC < 500/μl ) with or without symptoms of septicemia / fungemia or proven neutrophil dysfunction and not responding to antibiotics. Separation of granulocytes from a healthy donor is called granulocytapheresis.

We have done a handful of Granulocytapheresis procedures in our institute over the last year and a half. The typical indication for the procedure is neutropenia post stem cell transplant or AML induction chemotherapy. A single dose of granulocytes is enough in majority of cases, but in few cases we did alternate day granulocyte infusions ( 2-3) which resulted in better outcome for the patient. All age groups are eligible for granulocyte infusions; our youngest patient is a 2 yr old who got granulocte infusion with no side effects.

granulocyte infusion-bmt technique The procedure includes following steps:

Selection of donor and prerequisites: The donor should be of same blood group (granulocytes often have a greater than 0.5% hematocrit. So, ABO compatibility is required and a crossmatch must be performed ), all viral screenings should be negative and with acceptable CBC values.
Medication for mobilization of Granulocytes: The regimen include inj G-CSF @5mcg/kg two doses separated over 12 hours, with the second dose timed 2-3 hours before the actual procedure AND a single dose of dexamethasone 4mg, 12hrs before collection. The challenge in the procedure is collecting enough granulocytes to produce a therapeutic response. Donor faces transient myalgias which can be addressed with paracetamol. He/she can resume work after hydration and rest of couple of hours, just like with a regular blood donation. No long term side effects of concern is noted in donors.
Collection of Granulocytes: Done with the help of Frasenius - comtech machine. The procedure takes 1-3 hrs depending upon the volume to be collected. The recommended dose for adequate therapeutic response is 1.5 -4 X10¹⁰
Irradiation of the product : The granulocyte product should be irradiated before infusing to patient to prevent Transfusion associated-Graft Versus Host Disease. As the BMT unit at MGCH& RI is backed by a comprehensive facility, irradiation of the product is done immediately to avoid a detrimental delay.
Infusion of the product : The granulocytes should be give within 1-2hrs post collection for good results and better function – Granulocytes have a very short Half- life(8 hours)

Granulocyte infusion should definitely be considered in patients with prolonged neutropenia to decrease infection related mortality. The machine must be properly programmed and the operator specially trained for granulocyte collections. The BMT unit of MGCH&RI is equipped with in house apheresis machine with a well-trained technician. We use the procedure judiciously as a life saving measure in our patients.