IMMUNOHEMATOLOGY Polyethylene glycol antiglobulin tube versus gel microcolumn: influence on the incidence of delayed hemolytic transfusion reactions and delayed serologic transfusion reactions Jeffrey L. Winters, Elie M. Richa, Sandra C. Bryant, Craig D. Tauscher, Brenda J. Bendix, and James R. Stubbs BACKGROUND: Our institution has reported on delayed hemolytic transfusion reaction (DHTR) and delayed serologic transfusion reaction (DSTR) inci- dence changes. From January 1993 to June 2003, a polyethylene glycol (PEG) tube–based technique was used for red blood cell (RBC) antibody screen. In June 2003, a gel microcolumn technique was implemented. Impact of this on antibody detection and DHTR and DSTR incidence was investigated. STUDY DESIGN AND METHODS: Positive antibody screen frequency and antibody specificity from January 2002 to March 2003 and July 2003 to September 2004 were compared. Overall incidence of DHTR and DSTR as well as the number and identity of the RBC antibod- ies implicated from August 1999 through June 2003 (PEG) and July 2003 through July 2007 (gel) were compared. The mean length of hospital stay (LOS) and number of RBC units transfused per patient were compared. RESULTS: Equivalent numbers of antibody screens were performed with equivalent numbers of positive screens. Significant differences were not seen in the detection of clinically significant antibodies but signifi- cantly fewer clinically insignificant antibodies were detected with gel. Ninety-six DHTRs and DSTRs were diagnosed. The LOS and number of transfused RBC units were not statistically different. A significantly higher incidence of DHTRs and DSTRs was seen with PEG compared to the gel. CONCLUSION: The gel microcolumn method is similar to the PEG in detecting clinically significant antibodies but detects fewer clinically insignificant antibodies. The implementation of gel resulted in a lower incidence of DHTRs and DSTRs compared to PEG. D elayed complications of transfusion include delayed hemolytic transfusion reaction (DHTR) and delayed serologic transfusion reaction (DSTR). DHTR is the term used to describe the antibody-mediated destruction of transfused red blood cells (RBCs) resulting from an anamnestic or secondary immune response to foreign RBC antigens. 1 DSTR is the term used to describe sensitization of trans- fused RBCs, without hemolysis. 2 This may be due to a primary immune response with the development of a new antibody or an anamnestic response in an individual without accompanying evidence of enhanced clearance of the antibody-coated RBCs. Previous studies from the Mayo Clinic (Rochester, MN) demonstrated increasing incidence of DHTRs and DSTRs from 1978 through 1992. 3-6 Pineda and colleagues 7 subsequently reported that during the time period 1980 to 1998, a significant increase in the incidence of DSTR and a trend toward a decrease in the incidence of DHTR was ABBREVIATIONS: DHTR(s) = delayed hemolytic transfusion reaction(s); DSTR(s) = delayed serologic transfusion reaction(s); LOS = length of hospital stay. From the Department of Laboratory Medicine and Pathology, Division of Transfusion Medicine, and the Department of Health Science Research, Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota; and the Bio- logical Sciences Division, Department of Pathology, and Blood Bank/Transfusion Medicine, University of Chicago Medical Center, Chicago, Illinois. Address reprint requests to: Jeffrey L. Winters, MD, Depart- ment of Laboratory Medicine and Pathology, Division ofTrans- fusion Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905; e-mail: winters.jeffrey@mayo.edu. Received for publication November 12, 2009; revision received December 29, 2009, and accepted January 5, 2010. doi: 10.1111/j.1537-2995.2010.02609.x TRANSFUSION 2010;50:1444-1452. 1444 TRANSFUSION Volume 50, July 2010