Search

Background: Highly sensitized pediatric patients awaiting heart transplantation experience longer wait times and thus higher waitlist mortality. Similarly, children less than 2 years of age have increased waitlist times and mortality when compared to their older peers. To improve the likelihood of successful transplantation in these patients, various strategies have been utilized, including peri-operative plasmapheresis. However, limited data exists comparing plasmapheresis techniques for antibody reduction. This study’s aim was to compare the in vitro magnitude of isohemagglutinin titers (IT) and human leukocyte antigen (HLA) antibody removal and the time required between membrane-based plasmapheresis (MP) and centrifuge-based plasmapheresis (CP) incorporated into the extracorporeal (EC) circuit. Methods: Two MP (Prismaflex) and two CP (Spectra Optia, Terumo BCT) circuits were incorporated into four separate EC circuits primed with high titer, highly sensitized type O donor whole blood. Assays were performed to determine baseline IT and anti-HLA antibodies and then at 30-minute increments until completion of the run (two plasma volume exchanges) at two hours. Results: There was a decrease in anti-A and anti-B IgM and IgG titers with both MP and CP. Mean anti-A and anti-B titer reduction was by 4.625 titers (93.7% change) and 4.375 titers (93.8% change) using MP and CP, respectively. At 2 h of apheresis, CP reduced 62.5% of all ITs to ≤ 1:4, while MP reduced 50% of ITs to ≤ 1:4. Additionally, reduction of anti-HLA class II antibody to mean fluorescence intensity (MFI)

Background: Pure red cell aplasia (PRCA) is one of the important complications in major ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT). The established pathogenic factor of PRCA is the persistence of high anti-donor isohemagglutinins. As previously verified, the conditioning regimen and donor type were the factors associated with the development of PRCA in the small-sized studies. Currently, the prevalence, risk factors, and prognosis of PRCA are still worth studying to provide evidence. Methods: We conducted a prospective nested case-control study to determine the prevalence, donor-related factors, and the outcomes of PRCA following major ABO-incompatible transplantation. A total of 469 patients who underwent ABO-incompatible grafts were observed. Results: None of the patients were diagnosed with PRCA with minor or bidirectional ABO-incompatible HSCT. Thirteen of the187 patients (7%; 95% confidence interval [CI], 3.9%–11.9%) developed PRCA following major ABO-incompatible HSCT. Eleven of the 13 patients with PRCA recovered entirely. Donor type was an independent factor associated with post-HSCT PRCA (odds ratio [OR]=0.030; 95% CI, 0.003–0.321; P =0.004). The cumulative incidence rates of post-HSCT PRCA in the context of major ABO-incompatible HSCT were 0.8%, 13.1%, and 27.2% for the haploidentical donor (HID), unrelated donor, and matched related donor, respectively. No significant influence of PRCA on transplantation outcomes was observed. In conclusion, post-HSCT PRCA is a rare and less threatening complication in major ABO-incompatible HSCT. The majority of patients with PRCA could recover. Additionally, HIDs for recipients may have a low risk of post-HSCT PRCA. This trial was registered at www.chictr.org.cn (#ChiCTR2000041412). [ABSTRACT FROM AUTHOR]

BackgroundPure red cell aplasia (PRCA) is one of the important complications in major ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT). The established pathogenic factor of PRCA is the persistence of high anti-donor isohemagglutinins. As previously verified, the conditioning regimen and donor type were the factors associated with the development of PRCA in the small-sized studies. Currently, the prevalence, risk factors, and prognosis of PRCA are still worth studying to provide evidence.MethodsWe conducted a prospective nested case-control study to determine the prevalence, donor-related factors, and the outcomes of PRCA following major ABO-incompatible transplantation. A total of 469 patients who underwent ABO-incompatible grafts were observed.ResultsNone of the patients were diagnosed with PRCA with minor or bidirectional ABO-incompatible HSCT. Thirteen of the187 patients (7%; 95% confidence interval [CI], 3.9%–11.9%) developed PRCA following major ABO-incompatible HSCT. Eleven of the 13 patients with PRCA recovered entirely. Donor type was an independent factor associated with post-HSCT PRCA (odds ratio [OR]=0.030; 95% CI, 0.003–0.321; P=0.004). The cumulative incidence rates of post-HSCT PRCA in the context of major ABO-incompatible HSCT were 0.8%, 13.1%, and 27.2% for the haploidentical donor (HID), unrelated donor, and matched related donor, respectively. No significant influence of PRCA on transplantation outcomes was observed.In conclusion, post-HSCT PRCA is a rare and less threatening complication in major ABO-incompatible HSCT. The majority of patients with PRCA could recover. Additionally, HIDs for recipients may have a low risk of post-HSCT PRCA. This trial was registered at www.chictr.org.cn (#ChiCTR2000041412).

The risk of a hemolytic reaction during the transfusion of ABO non‐identical PC is determined by the presence of natural anti‐A IgM antibodies, the titer of which may increase after infections. The aim of the study was to evaluate the titer of anti‐A isohemagglutinins in platelet concentrate (PC) obtained by apheresis from group O donors who experienced SARS‐CoV‐2 infection, and to compare the titer before and after infection. A retrospective single‐center analysis of 21 PC donors with a previous COVID‐19 history was performed. The results showed neither a statistically important increase in the anti‐A IgM antibody titers nor a significant correlation between the anti‐A IgM antibody level and anti‐SARS‐CoV‐2S1 antibody titer in the donors with an asymptomatic or mild COVID‐19. Further population‐based studies on anti‐A titers are necessary for a comprehensive assessment of this phenomenon. [ABSTRACT FROM AUTHOR]