- Email: [email protected]
32-P
S80
Abstracts
32-P
IS THE USE OF DTT IN PRA TESTS BY ELISA ASSAYS NECESSARY? YES IT IS Andreia V. Candido, Daniela C. Duarte, Andreia Bueno-Silva, Carolina Kneib, Renata Glehn-Ponsirenas, Cristina Q.C. von Glehn. Laboratorio de Imunogenetica, Pontificia Universidade Catolica do Parana, Curitiba, Parana, Brazil Aim: The PRA test detects the presence of circulating IgG, which is considered deleterious. The presence of IgM can block the IgG, because of the anti-idiotypic net formation or the IgM link to IgG. A way to solve this problem can be the use of DTT, which is able to break the IgM molecule and its link to the antigen as well to the IgG. Methods: We used the PRA by ELISA method (LAT-M One Lambda kit) for 2000 samples, (1000 with DTT and 1000 without), analyzing only class I results. The Chi-square test was used to calculate if these differences were significant (p⫽0,05). We considered as an increase the results with more than 20% of difference in the PRA LAT-M sample index. Three groups were formed based on sample index values: group 1: sI ⬍ 0,80 (positive); group 2: sI 0,80 – 1,20 (gray zone); group 3: sI ⬎1,20 (negative). Scope: The main objective of this study was to verify if the sera treated with DTT had similar results when compared to the same sera not treated with it and based on this data, establish a new PRA protocol for our laboratory. Conclusions: For the sera without DTT treatment we found 54.8% of the samples classified as group 1, 17.4% as group 2 and 27.8% as group 3. Treating the sera of the same samples with DTT, we had a decrease in group 1, from 54.8% to 32%. However, for samples classified as group 2 and 3 we had increases. Group 2 samples increased to 29.3%, while group 3 samples increased to 38.7%. Considering the data above, we verified that 23% of the total of patients in the study had an expressive increase in their sl. Among 1000 patients tested, 47% didn⬘t suffer any changes in sl, 46% suffered an increase and 7% suffered a decrease (p⬎0.001). By that, samples treated with DTT offer a higher level of security when it comes to detection of deleterious antibodies, since we can discard or confirm the existence of false negative results.
33-P
EXPEDITED DELIVERY OVERCOMES SERUM SUPPLY-CHAIN LOGISTICAL PROBLEMS Michael D. Gauteaux, David F. Kiger, April Dollar-Bates. HLA/Immunogenetics Lab, Wake Forest University Health Sciences, Winston-Salem, NC, USA Aim: A common problem in many histocompatibility laboratories is ensuring that “current” patient serum is available for antibody testing and crossmatch analyses. ASHI and UNOS standards (ASHI D.4.6.23, D.4.6.24 & UNOS F3.200) require that laboratories obtain specimens periodically for antibody identification. Unfortunately, laboratories must depend on dialysis centers to procure and ship patient samples to them in an efficient and timely manner. This became a greater logistical problem for our laboratory after our recent relocation off-site from the medical center. Methods: It is our practice to reject samples from dialysis centers which are received more than seven days after their draw date. It quickly became apparent that many specimens spent an excessively long time in transit via the U.S. mail, often exceeding two weeks or more. In response to this disturbing trend, we have developed a Quality Improvement Initiative plan to eliminate the problem. The core of this plan is a program involving the use of Fed Ex Express Saver Clinic Paks for the receipt of PRA samples each month. This is particularly helpful as the Fed Ex airbills come pre-printed with our new address, saving any confusion among the centers as to our new location. Scope: Initially, pre-printed airbills exhibiting, in addition to our new address, our Fed Ex account number and premarked Express Saver service were distributed to selected dialysis centers, as well as the Fed Ex Express Saver Clinic Paks. Dialysis centers that seemed to have the longest sample transit times were targeted first, followed shortly after by the remainder of the dialysis clinics. In addition, upon request, we also furnished any mailers or tubes they may have needed in order to adequately draw samples for all of their patients currently on the WFUBMC renal transplant list. Near the end of each month, we notified the centers of any delinquent patient samples via fax or phone call, giving them adequate time to draw (or in some cases re-draw) a patient’s sample. After a specified month was over, any patients still delinquent were listed and distributed to the transplant coordinators for follow up. Conclusions: Since we originally began this Quality Improvement, our results have been remarkable. The number of required monthly samples received in our lab on time has increased. It is now rare that we have to arrange for special transport in order to obtain final crossmatch specimens. In April of 2006, we had a 0% rejection rate of samples on the basis of our seven day cutoff, compared to July of 2005 when more than 5% of our overall samples were rejected. All of the changes implemented and described in this quality improvement process have had a negligible cost for our laboratory. We believe this process has ensured our ability to process each patient’s serum in a timely manner, therefore allowing us, in turn, to perform final crossmatches expediently. Furthermore, it takes very little extra work for us to maintain this system. The benefits to the laboratory in terms of reduced time and labor, and most importantly the benefits for the patient in having current serum on hand for crossmatch have been tremendous.
Abstracts
32-P
IS THE USE OF DTT IN PRA TESTS BY ELISA ASSAYS NECESSARY? YES IT IS Andreia V. Candido, Daniela C. Duarte, Andreia Bueno-Silva, Carolina Kneib, Renata Glehn-Ponsirenas, Cristina Q.C. von Glehn. Laboratorio de Imunogenetica, Pontificia Universidade Catolica do Parana, Curitiba, Parana, Brazil Aim: The PRA test detects the presence of circulating IgG, which is considered deleterious. The presence of IgM can block the IgG, because of the anti-idiotypic net formation or the IgM link to IgG. A way to solve this problem can be the use of DTT, which is able to break the IgM molecule and its link to the antigen as well to the IgG. Methods: We used the PRA by ELISA method (LAT-M One Lambda kit) for 2000 samples, (1000 with DTT and 1000 without), analyzing only class I results. The Chi-square test was used to calculate if these differences were significant (p⫽0,05). We considered as an increase the results with more than 20% of difference in the PRA LAT-M sample index. Three groups were formed based on sample index values: group 1: sI ⬍ 0,80 (positive); group 2: sI 0,80 – 1,20 (gray zone); group 3: sI ⬎1,20 (negative). Scope: The main objective of this study was to verify if the sera treated with DTT had similar results when compared to the same sera not treated with it and based on this data, establish a new PRA protocol for our laboratory. Conclusions: For the sera without DTT treatment we found 54.8% of the samples classified as group 1, 17.4% as group 2 and 27.8% as group 3. Treating the sera of the same samples with DTT, we had a decrease in group 1, from 54.8% to 32%. However, for samples classified as group 2 and 3 we had increases. Group 2 samples increased to 29.3%, while group 3 samples increased to 38.7%. Considering the data above, we verified that 23% of the total of patients in the study had an expressive increase in their sl. Among 1000 patients tested, 47% didn⬘t suffer any changes in sl, 46% suffered an increase and 7% suffered a decrease (p⬎0.001). By that, samples treated with DTT offer a higher level of security when it comes to detection of deleterious antibodies, since we can discard or confirm the existence of false negative results.
33-P
EXPEDITED DELIVERY OVERCOMES SERUM SUPPLY-CHAIN LOGISTICAL PROBLEMS Michael D. Gauteaux, David F. Kiger, April Dollar-Bates. HLA/Immunogenetics Lab, Wake Forest University Health Sciences, Winston-Salem, NC, USA Aim: A common problem in many histocompatibility laboratories is ensuring that “current” patient serum is available for antibody testing and crossmatch analyses. ASHI and UNOS standards (ASHI D.4.6.23, D.4.6.24 & UNOS F3.200) require that laboratories obtain specimens periodically for antibody identification. Unfortunately, laboratories must depend on dialysis centers to procure and ship patient samples to them in an efficient and timely manner. This became a greater logistical problem for our laboratory after our recent relocation off-site from the medical center. Methods: It is our practice to reject samples from dialysis centers which are received more than seven days after their draw date. It quickly became apparent that many specimens spent an excessively long time in transit via the U.S. mail, often exceeding two weeks or more. In response to this disturbing trend, we have developed a Quality Improvement Initiative plan to eliminate the problem. The core of this plan is a program involving the use of Fed Ex Express Saver Clinic Paks for the receipt of PRA samples each month. This is particularly helpful as the Fed Ex airbills come pre-printed with our new address, saving any confusion among the centers as to our new location. Scope: Initially, pre-printed airbills exhibiting, in addition to our new address, our Fed Ex account number and premarked Express Saver service were distributed to selected dialysis centers, as well as the Fed Ex Express Saver Clinic Paks. Dialysis centers that seemed to have the longest sample transit times were targeted first, followed shortly after by the remainder of the dialysis clinics. In addition, upon request, we also furnished any mailers or tubes they may have needed in order to adequately draw samples for all of their patients currently on the WFUBMC renal transplant list. Near the end of each month, we notified the centers of any delinquent patient samples via fax or phone call, giving them adequate time to draw (or in some cases re-draw) a patient’s sample. After a specified month was over, any patients still delinquent were listed and distributed to the transplant coordinators for follow up. Conclusions: Since we originally began this Quality Improvement, our results have been remarkable. The number of required monthly samples received in our lab on time has increased. It is now rare that we have to arrange for special transport in order to obtain final crossmatch specimens. In April of 2006, we had a 0% rejection rate of samples on the basis of our seven day cutoff, compared to July of 2005 when more than 5% of our overall samples were rejected. All of the changes implemented and described in this quality improvement process have had a negligible cost for our laboratory. We believe this process has ensured our ability to process each patient’s serum in a timely manner, therefore allowing us, in turn, to perform final crossmatches expediently. Furthermore, it takes very little extra work for us to maintain this system. The benefits to the laboratory in terms of reduced time and labor, and most importantly the benefits for the patient in having current serum on hand for crossmatch have been tremendous.