The "Protocol for in-house production of cryoprecipitate" was published by the Japan Society of Transfusion Medicine and Cell Therapy in 2016. It outlines the standard operating procedures for the preparation of cryoprecipitate (CRYO), and recommends measuring the percent recovery of fibrinogen in CRYO at least once every six months for quality control. Based on the protocol, we evaluated 51 CRYO preparations produced in our hospital, derived from 51 fresh frozen plasma (FFP) preparations distributed by Japan Red Cross Blood Center.

The mean±standard deviation (SD) volume of the CRYO preparations was 56.1±6.4 ml. There was a significant correlation between the fibrinogen content of CRYO and FFP preparations (r = 0.965; p < 0.001). The mean±SD fibrinogen content of CRYO preparations was 528.3±152.1 mg, and the maximum difference among CRYO preparations was 655.2 mg. The mean±SD, median, maximum and minimum percent recovery of fibrinogen in CRYO preparations was 48.0±6.2%, 48.2%, 60.5% and 33.1%, respectively. There was a significant correlation between the percent recovery of fibrinogen in CRYO and the fibrinogen content in FFP preparations (r = 0.788; p < 0.001). This suggests that we should consider not only problems with preparation techniques but also low fibrinogen content of FFP preparations when percent recovery of fibrinogen in CRYO is below 40%.

Background: Detection of coexisting alloantibodies is important because patients with autoantibodies often also have alloantibodies. The polyethylene glycol (PEG) adsorption method is a commonly used autoantibody adsorption method. However, the PEG adsorption method reportedly also adsorbs low titers of alloantibodies. While there are reports that an autoantibody adsorption method that uses low ionic strength solution (LISS) is a quick and useful autoantibody adsorption method, this method is not commonly used in Japan. We report 3 cases for which the LISS adsorption method was useful for autoantibody adsorption and detection of coexisting alloantibodies.

Patients and Methods: We used the LISS adsorption method for autoantibody adsorption in 3 patients with autoantibodies. Autoantibodies of one patient who had not received a transfusion within the previous 3 months were adsorbed using autologous red blood cells (RBCs), while those of the remaining two patients who received a transfusion within the previous 3 months were adsorbed using Rh-, Kidd- and Diego-matched enzyme-treated allogeneic RBCs.

Results: Low-titer alloantibodies were detected in all 3 cases using the LISS adsorption method.

Conclusion: The detection of low-titer alloantibodies using the LISS adsorption method suggests efficient adsorption of autoantibodies. Therefore, the LISS adsorption method is useful for detecting coexisting alloantibodies in patients with autoantibodies.