Background/Case Studies: Hematopoietic stem cell transplant (SCT) for chronic granulomatous disease with McLeod Syndrome (CGD/MLS) can be curative. SCT can be challenging due to the lack of readily available Kx negative RBCs. To reduce risk of antibody formation and due to the lack of adequate available units through the rare blood donor program, two blood centers (A and B) partnered to develop a small volume collection, RBC glycerolization and deglycerolization protocol for a 3-year-old patient needing SCT. The below process was validated, and collections are ongoing.
Study
Design/Methods: Blood center A worked with hospital nurses to devise a collection system that would minimize the risk of contamination. An intravenous access device (IVAD) was placed to facilitate collection. The patient received normal saline prior to and after collection. At each collection, 10 cc/kg whole blood (WB) is collected into a 500 ml CPD Blood Pack (Fenwal Bioflex). The amount of anticoagulant (AC) requires adjustment to preserve a 7:1 WB:AC ratio. To remove AC, a neonatal blood administration syringe is sterilely docked onto the primary container using the sterile tubing welder (TSCD-II – Terumo BCT) and a calculated amount is removed.Since the 16-gauge needle cannot be used for collection, a male Luer lock from a dry collection bag (Fresenius Kabi) is sterilely docked onto the collection line of the blood bag.This Luer lock is attached to a series of syringes on stopcocks that is ultimately connected to the IVAD.Whole blood is manually drawn in 10cc increments into one syringe, and then pushed into the blood bag. After the desired amount is collected, the unit is sent to the blood center B. Upon arrival, a validated method for small volume closed system is utilized to glycerolize and deglycerolize the units. To validate the small volume method, units of whole blood were split into 100 mL and 125 mL. These units were glycerolized and deglycerolized utilizing the small bowl on the cell processing ACP 215 (Haemonetics).
Results/Findings: During validation, 19 test cases were run (results in table). The free hemoglobin (HGB) on each unit used during validation was less than 150 mg/dL with an average of 68% of red blood cell recovery on the 100 mL units and 90% red blood cell recovery on the 125mL units. A test unit from our patient was also collected, glycerolized and deglycerolized to ensure the patient's acanthocytic cells would behave the same as normal donor RBCs. We obtained a free HGB of less than 150 mg/dL and 94% red blood cell recovery. Of note, this method allows for deglycerolized RBCs to be stored for up to 14 days at 1-6ºC. Conclusions: An effective method to collect, glycerolize, and deglycerolize was developed and validated to provide transfusion support for a patient with CGD/MLS needing SCT. Collections are ongoing until an adequate number of units are available for the patient to proceed with SCT.
