Efficacy of HLA virtual cross‐matched platelet transfusions for platelet transfusion refractoriness in hematopoietic stem cell transplantation

Abstract

BACKGROUND Cross‐matched platelet (cross‐matched PLT) transfusion is effective for immune‐mediated platelet transfusion refractoriness (PTR), but is more costly and time‐consuming for physical cross‐match than using standard PLT units. Recent studies have reported the utility of human leucocyte antigens (HLA) virtual cross‐matched PLT (HLA‐matched PLT) that is defined as HLA‐A/B matched or no antibody against donor‐specific antigen. Here, we evaluated the effect of HLA‐matched PLTs for PTR in post hematopoietic stem cell transplant (HSCT) recipients. STUDY DESIGN AND METHODS Our study included a total of 241 PLTs in 16 patients who underwent HSCT at Okayama University Hospital between 2010 and 2017, receiving either HLA‐matched or cross‐matched PLTs. We calculated the 24‐hour corrected count increments (CCI‐24) to evaluate the effect of PLTs. A CCI‐24 ≥ 4500 was considered to be a successful transfusion. RESULTS We analyzed 139 cross‐matched PLTs and 102 HLA‐matched PLTs. In the immune‐mediated PTR, the rate of successful transfusion was 60.5% for cross‐matched PLT and 63.4% for HLA‐matched PLT (p = 0.825). On the other hand, the median CCI‐24 for cross‐matched PLT transfusions and HLA‐matched PLT transfusions were 1856 and 5824 (p < 0.001), with a success rate of 28.1 and 54.1% in cases with non‐immune‐mediated PTR, respectively (p = 0.001). CONCLUSION The effectiveness of HLA‐matched PLT is not inferior to cross‐matched PLT. This result indicates that physical cross‐match can be omitted in post HSCT PTR.

Platelet transfusion refractoriness: how do I diagnose and manage?

“…Platelet crossmatching and HLA matching are frequently used, and the success rate of these strategies is comparable. [32][33][34]…”

Prevention of platelet transfusion refractoriness by platelet antigen gene matching: a systematic review and meta-analysis

“…This index was reported in six publications (8)(9)(10)(11)13,14), and the heterogeneity test showed no statistically significant difference (I 2 =43%, P=0.12) using the fixed-effect mode, and the obtained effective rate of the two intervention methods was compared (OR =4.90, 95% CI: 3.50-6.86, Z=9.23, P<0.00001), as shown in Figure 3.…”

“…Only publications (11) mentioned the use of randomization, without necessarily detailing the specific method. None of the publications mentioned whether there was classification concealment or a blind method implementation, and the phenomenon of case loss was reported in only three publications (8,9,11), although the data was still complete because the case loss was not included in the outcome statistics. There were no selective reporting in all included studies results, and other risk of bias was unknown, as shown in Table 2.…”

Prozone rates in the solid‐phase platelet crossmatch assay and correlation with class I HLA antibody levels

“…Immune‐mediated platelet transfusion‐refractoriness is caused predominantly by patient antibodies against foreign class I human leukocyte antigens groups A and B (HLA‐A and HLA‐B) and, more rarely, by patient antibodies against foreign human platelet antigens (HPAs) 3–6 . While only the cause of 20%–25% of cases, immune‐mediated platelet transfusion‐refractoriness can be successfully mitigated by selecting platelet units that avoid recipient anti‐platelet antibodies 3,4,7–11 . Multiple in vitro approaches exist for the identification of compatible platelet inventory for such patients, including solid‐phase platelet crossmatches, class I HLA antibody (HLA‐Ab)/antigen testing, and HPA antibody/antigen testing 8–18 .…”

“…While only the cause of 20%–25% of cases, immune‐mediated platelet transfusion‐refractoriness can be successfully mitigated by selecting platelet units that avoid recipient anti‐platelet antibodies 3,4,7–11 . Multiple in vitro approaches exist for the identification of compatible platelet inventory for such patients, including solid‐phase platelet crossmatches, class I HLA antibody (HLA‐Ab)/antigen testing, and HPA antibody/antigen testing 8–18 . Each approach has diagnostic limitations, however, so algorithms integrating multiple approaches have been proposed 17,19 …”