Background/Case Studies: Platelet refractoriness presents a challenge for both the clinical team and blood bank. Our institution uses an algorithmic approach to evaluating these patients. Starting with clinical evidence of platelet refractoriness, patients are typically evaluated with a 14-unit platelet crossmatch (Capture-P, Werfen). Patients with greater than 20% incompatible are evaluated for antibodies to human leukocyte antigens (HLA; LabScreen Single Antigen, ThermoFisher). If antibodies to human platelet antigens (HPA) are suspected, then samples are submitted for testing (Pak Plus, Werfen). Herein we describe one-year experience with this algorithmic approach.
Study
Design/Methods: Laboratory records were reviewed to identify all physical platelet crossmatches performed at our institution in the 2024 calendar year. The records of these patients were further reviewed for HLA and HPA antibody results.
Results/Findings: In 2024, 56 patients were evaluated for platelet refractoriness, 35 men and 21 women. Of the 66 platelet crossmatches performed, 34 were subsequently tested for HLA antibodies and 12 were tested for HPA antibodies. HLA antibodies were identified in 15 patients and HPA antibodies were not detected in any of the tested patients. One case failed to identify HLA or HPA antibodies; however, cross-matched platelets successfully increased the platelet count. Of the 35 men, antibodies were identified in 7. Of the 21 women, antibodies were identified in 9. Conclusions: Our experience with laboratory evaluation of platelet refractory patients may be informative for how hospitals establish local protocols.
