Abstract
An estimated 20% of platelet transfusion refractoriness (PTR) is reported to be related to immunological factors, 95% or more of which are anti-human leukocyte antigen (anti-HLA) antibodies. Although the corrected count increment at 1-hour post-transfusion (CCI-1) is commonly used to assess the efficacy of platelet transfusion, CCI-1 is not always routinely measured owing to the need for additional blood collection. To develop a method for the easy prediction of immunological PTR, we retrospectively analyzed the medical records of 50 patients with PTR in our hospital and who were screened for anti-HLA and anti-HPA antibodies from July 2005 to December 2018. Among these patients, 96% (48 patients) had hematological disorders, and antibody-dependent PTR was observed in 23 patients. In this study, significant factors for immunological PTR were sex (female), C reactive protein (CRP) levels of < 2.2 mg/dL, and CCI-1 of < 3,500/μL. Using two factors, female sex and CRP levels of ≤ 2.2 mg/dL, we were able to predict immunological PTR with a sensitivity of 69.6% and a specificity of 77.8%. Furthermore, among patients with a hematological malignancy, the sensitivity and specificity increased to 86.7% and 75.0%, respectively. Although CCI-1 predicted immunological PTR with a specificity of ≥ 90%, it was not measured in 38% of patients. Currently, CCI-1 is the standard method for distinguishing PTR. Therefore, if platelet transfusion is ineffective, a medical technologist should suggest the measurement of CCI-1 to the attending doctor as well as organize the information, such as the disease that causes PTR, sex, and CRP level, so that antiplatelet antibody testing is performed promptly.
