A medical technologist reports that her hospital transfusion service recently received an order for two units of irradiated, leukocyte reduced RBCs for transfusion of a group O, Rh positive pregnant sickle cell disease patient who was suffering a sickle cell 'crisis' at 23 weeks gestation. The physician did not request that the RBC donors be CMV seronegative or that the phenotype of the donor RBCs be matched with the C, E and K-antigen phenotype of the patient. The patient had a negative screen for unexpected red cell antibodies. The technologist contacted the local blood supplier and requested two units of group O, Rh positive, leukocyte reduced, irradiated RBCs, as requested by the physician. However, she also requested (in accordance with their local transfusion service policy) that the RBCs be CMV seronegative (because the patient was pregnant), and that the red cells be Hgb S negative and C-, E-, K-antigen negative because the patient has sickle cell disease. The inquiring medical technologist is uncertain why the donor red cell units had to be irradiated, but did comply with the physician's order. She is aware that intrauterine transfusions must be irradiated to prevent Graft versus Host Disease (GVHD) of the fetus/newborn, but she was not aware of random donor RBCs causing GVHD in pregnant women. She 'assumes' that the physician ordered the RBCs to be irradiated because pregnancy imposes some degree of immunosuppression so as to not reject the fetus, and because at her hospital the fetus would be transfused with leukocyte reduced, CMV seronegative, irradiated RBCs if it needed a transfusion shortly after birth. She wonders if there are clear guidelines or documentation that supports giving irradiated RBCs to a pregnant woman? If so, might the new mom's "slight immunosuppression" continue for several days or weeks beyond delivery so that there might be a concern should the mother require blood products just after delivery as well as during pregnancy?

The following comments have been received.

1. Editor's Note: Please see the e-Network Forum discussion How do blood banks know when a patient should get irradiated blood, if the patient's doctor forgets to order the blood to be irradiated?

2. A Consultant Hematologist for the National Blood Service in the UK reports that in his opinion there is no need to irradiate blood products merely because they need to be transfused to a pregnant patient.

3. Dr. Susan F. Leitman, Chief of the Blood Services Section, Department of Transfusion Medicine at the National Institutes of Health (attribution used with permission) reports that she is not aware of a case of TA-GVHD having occurred in a pregnant woman, nor is she aware of a mechanism whereby pregnancy alone would confer a degree of immune suppression sufficient to increase the risk of TA-GVHD. She wonders if the physician who ordered irradiated RBCs as reported in the case above and in the ADDENDUM of Apr. 17, 2006, might have done so with the goal of protecting the fetus (as opposed to the mother) from TA-GVHD risk, and therefore confused the well-documented incidence of TA-GVHD following intrauterine transfusion with a 'hypothetical' risk of TA-GVHD from a maternal transfusion. However, the risks do not overlap since a fetus is not at risk of TA-GVHD from passenger lymphocytes transfused to its mother. Dr. Leitman acknowledges that all blood product transfusions are irradiated at the NIH, as that institution practices 'universal irradiation.' However, she adds that in an institution not practicing universal irradiation, she would not recommend irradiation of cellular blood products merely because a transfusion recipient is pregnant. With regards to the use of CMV seronegative blood for a pregnant woman, at the very least she would want to know the CMV serostatus of the mother before this was considered. She is also of the opinion that there is no specific indication for leukocyte reduction of units transfused during pregnancy, in an institution which is not practicing universal leukoreduction. Dr. Leitman agrees that providing phenotype-compatible red cell units to sickle cell disease patients is a medically justifiable practice, whenever possible. Finally, it is interesting to her that the CMV negative, phenotype-compatible blood product order (see case report) was generated by the transfusion service (per their policies) and not by the ordering physician, making it sound as though the ordering physician may not even be aware of these practices. At the NIH, the transfusion medicine staff meet bimonthly with the major sickle cell treating physicians to review odd or unusual cases and to review and refresh transfusion and apheresis guidelines.

ADDENDA Apr. 23, 2006

4. At the Los Angeles County+USC Medical Center, a pregnant sickle cell disease patient who needs a transfusion would routinely receive leukocyte reduced (CMV low risk) red cells, since essentially all RBC units used at that facility are leukocyte reduced. Furthermore, a pregnant sickle cell disease patient would receive donor RBCs that are matched to the patient's C, E, K phenotype. The LAC+USC blood bank does not routinely provide irradiated RBCs for pregnant patients, unless specifically requested (and justified) by the patient's physician. Furthermore, RBC units used for adults with sickle cell disease are not screened for hgb S, unless specifically requested (and justified) by a clinician who wants to quantify and trend a patient's hgb S levels (such as by serial hemoglobin electrophoresis).

ADDENDA Apr. 25, 2006

5. A transfusion medicine physician in Buenos Aires, Argentina reports that in his practice he does not recommend blood products be irradiated, merely because a recipient is pregnant. He points out that US and UK colleagues also do not recommend the routine irradiation of blood components for pregnant women (Przepiorka D, LeParc G, Stovall MA, Werch J, Lichtiger B. Use of Irradiated Blood Components. Practice Parameter. Am J Cl Path 1996; 106 (1): 6-11) and BCSH Blood Transfusion Task force. Guidelines on gamma irradiation of blood components for the prevention of transfusion-associated graft-versus-host disease. Transfusion Medicine 1996; 6: 261-271).

6. A transfusion medicine physician in Edinburgh reports that the following information, which is from a table that appears in the UK transfusion handbook 4th edition, lists indications for the use of gamma irradiated cellular blood components. He points out that merely being pregnant is not one of the listed indications.

• Transfusions from first or second degree relatives
• Any granulocyte transfusion for any recipient
• All recipients of allogeneic haemopoietic stem cell (HSC) grafts, from start of conditioning therapy and while patient remains on GvHD prophylaxis
• Blood transfused to allogeneic HSC donors before or during the harvest of their HSC
• Patients who will have autologous HSC graft:
  • Any transfusion within 7 days of the collection of their HSC
  • Any transfusion from the start of conditioning therapy until 3 months post transplan to 6 months post transplant if conditioning Total Body Irradiation has been given
• Hodgkin's disease
• HLA selected platelet units
• Patients receiving purine analogues (fludarabine, cladribine, deoxycoformycin)
• Intrauterine transfusion
• Exchange transfusion
• Red cell and platelet transfusion in neonates (only if there has been a previous IUT or if blood is from first or second degree relative)
• Congenital immunodeficiency with defective cell mediated immunity (e.g., SCID, Di George's, Wiskott Aldrich, Purine nucleoside deficiency, reticular dysgenesis, ADA, Ataxia telangectasia, chronic mucosal candidiasis, MHC class 1 or 2 deficiency)

Notes

1. Red cell, platelets and granulocyte componets must be irradiated for all at risk patients. It is not necessary to irradiate fresh frozen plasma, cryoprecipitate, cryosupernatant or plasma derivatives
2. It is not necessary to irradiate components for patients with solid tumors, organ transplants, HIV or aplastic anaemia

ADDENDA Apr. 26, 2006

7. A transfusion medicine physician in the Midwest reports that while he concurs with comments about a lack of evidence to support a request for irradiation of blood products for pregnant women, he is supportive of the use of leukoreduced units to lower risk of CMV transmission for that patient group. In his opinion, the study by Boppana entitled Intrauterine transmission of cytomegalovirus to infants of women with preconceptional immunity. N Engl J Med. 2001 May 3;344(18):1366-71 suggests the potential for second strain infection. Hence, in his experience some centers prefer to provide CMV reduced risk products to all pregnant patients and premature infants.

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