A Transfusion Governance Coordinator in Sydney, Australia would like to know if any colleague is aware of any adverse event associated with the serial administration of ABO non-identical cryoprecipitate and red blood cells through the same blood administration tubing, such as when group A red cells have been administered following the infusion of group O cryoprecipitate without flushing the line with saline between those products. The adverse events that she wonders about include hemolysis due to residual anti-A in the tubing (manifested by hemoglobinemia or hemoglobinuria), agglutination of red cells in the blood administration tubing, or any other complication.

Editor's question: In addition to commenting on the specific question raised from Australia, would colleagues also comment on their experience of adverse events following serial administration of group A, group B or group AB red cells following group O (or otherwise ABO incompatible) plasma or platelets, without flushing the line with saline between those products.

The following comments have been received.

ADDENDA Aug. 13, 2005

1. A very experienced transfusion medicine physician at an academic center in a southern state reports that he is aware of a few reports of "interdonor" hemolysis in the literature, these reports typically describe either the passive infusion of antibodies that react with circulating transfused red cells or donor antibodies produced by "passenger" lymphocytes seen with transplants that similarly react with circulating transfused red cells.

• West NC, Jenkins JA, Johnston BR, Modi N. Interdonor incompatibility due to anti-Kell antibody undetectable by automated antibody screening. Vox Sang. 1986;50(3):174-6.
• Zettner A, Bove JR. Hemolytic transfusion reaction due to interdonor incompatibility. Transfusion. 1963 Jan-Feb;3:48-51.
• Brecher ME, Moore SB, Reisner RK, Rakela J, Krom RA. Delayed hemolysis resulting from anti-A1 after liver transplantation. Am J Clin Pathol. 1989 Feb;91(2):232-5.

He comments that one would think there might be a problem with the sequential infusion of ABO incompatible blood components through a common line leading to hemolysis in the line, but in fact, in his extensive experience, he is not aware that this has actually been observed. He wonders if the absence of observed hemolysis in the line is likely due to the fact that hemolysis via the classical pathway of complement activation is triggered by antigen-bound antibody molecules. He points out that it is the binding of a specific part of the antibody molecule to the C1 component that initiates this pathway. This initial enzyme, C1, is a complex formed through a calcium-dependent association between two reversibly interacting subunits, C1q and C1r2s2. Since blood components are anti-coagulated with citrate, the calcium is not available for this calcium dependent step. Citrate is metabolized by the liver, so this is not a factor for the blood in the catheter. Once the blood components leave the catheter, mixing leads to hemodilution of the antibodies and ABO incompatible antibodies such as might be found in platelets are likely also taken up by the A and B antigens that might be found on endothelial cells. Despite the lack of complement activation in the catheter, red cell aggregation might occur. Therefore, he does think that it is prudent to flush the lines prior to hanging a sequential ABO incompatible unit.

ADDENDA Aug. 15, 2005

2. W. John Judd, FIBMS, MIBiol, Professor of Immunohematology at the University of Michigan Medical Center (attribution used with permission) offers two comments relative to this discussion:

1. Anti-A and anti-B titers are higher in cryoprecipitate than they are in normal plasma, due to the concentration of immunoglobulins during a freeze-thaw process. He asks "Ever notice that in a tube of unmixed thawed serum the fluid at the top of the tube is almost like water, and that at the bottom of the tube is of a darker hue?" He also recalls that when cryoprecipitate is manufactured, one does not mix the plasma after thawing before centrifugation. This protein concentrating effect is the reason why tubes of thawed antibodies must be well mixed before use.
2. Citrated plasma may not be as anticomplementary as the colleague from the southern USA suggests. He bases his cautionary comment on experience when trying to automate anti-A/B hemolysin tests on ACD plasma samples. He and his collaborators were surprised to find that there is active complement in ACD plasma, and he expects there is in CPD plasma.

ADDENDA Aug. 17, 2005

3. A transfusion medicine physician in California would like to challenge the statement of Professor Judd in Addendum #2 above based on published data in the article by Cooke JV, Holland PV, Shulman NR. Ann Intern Med 1968;68:39-47, in which the authors measured the anti-A and anti-B in Cryoprecipitate and found that the titers were lower than in the starting plasma. Apparently, in using some of the ice to resuspend the Cryoprecipitate, one actually dilutes the anti-A and anti-B levels in the final product.

ADDENDA Aug. 18, 2005

4. A transfusion medicine physician in North Carolina thinks that a paper by Zapf and Loos supports Professor Judd's second contention that citrated plasma may not be as anticomplementary as many believe. (see Immunobiology. 1985 Sep;170(3):123-32. Effect of EDTA and citrate on the functional activity of the first component of complement, C1, and the C1q subcomponent. Zapf S, Loos M.) In that paper the authors report that after dissociation of C1 by citrate, 100% of the original C1q activity is recoverable on addition of C1q deficient serum as a source of C1r and C1s.

ADDENDA Aug. 19, 2005

5. A colleague in New York wishes to add to this discussion his concerns regarding the infusion of ABO incompatible antibody or ABO incompatible soluble antigen, even in the amounts found in a product with as small a volume as cryoprecipitate. He points out that endothelial cells, white cells, platelets and virtually all the other cells that transfused blood comes in contact with carry ABO antigens, and many have Fc or C1q receptors. His group has made the case both in vitro and clinically that transfusions of ABO mismatched blood components may have deleterious consequences far beyond whatever happens or doesn't happen to the red cells. So at his hospital, their preference, especially for products like cryoprecipitate is to always give ABO identical, if at all possible. He offers the following reference as a point of discussion:

Heal JM, Liesveld JL, Phillips GL, Blumberg N. What would Karl Landsteiner do? The ABO blood group and stem cell transplantation. Bone Marrow Transplant. 2005 Jul 25; (Epub ahead of print)

Hematology-Oncology Unit, Department of Medicine, University of Rochester Medical Center, Rochester, NY, USA.

Summary: ABO blood group antigens, of great importance in transplantation and transfusion, are present on virtually all cells, as well as in soluble form in plasma and body fluids. Naturally occurring plasma IgM and IgG antibodies against these antigens are ubiquitous. Nonetheless, the ABO blood group system is widely ignored by many transfusion services, except for purposes of red cell transfusion. We implemented a policy of transfusing only ABO identical platelets and red cells in patients undergoing stem cell transplantation or treatment for hematologic malignancies. Major bleeding episodes have occurred in about 5% of patients undergoing induction therapy for acute leukemia as compared with 15-20% in the literature. Overall survival times appear to be superior to that in historical cohorts. In 2002-2004, treatment-related mortality at 100 days in our Blood and Marrow Transplant Unit was 0.7% for autologous transplants (n=148), 13% for sibling allogeneic transplants (n=110), and 24% (n=62) for matched unrelated allogeneic transplants, suggesting that our approach is safe. We speculate that more rigorous efforts on the part of transfusion services to provide ABO identical blood components, and to remove incompatible supernatant plasma, when necessary, might yield reduced morbidity and mortality in patients undergoing stem cell transplantation.

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Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator