When a patient is having platelet transfusion refractoriness that may be due to immunological causes, the patient’s HLA genotype and potential HLA antibodies must be analyzed (B –HLATrb, https://www.veripalvelu.fi/terveydenhuollon-ammattilaiset/laboratoriopalvelut/tutkimusohjekirja). If the patient carries HLA antibodies that potentially explain the transfusion refractoriness, testing HLA-typed platelet products for the patient is recommended. However, a physician from the Blood Service should always be consulted before ordering HLA-typed platelets for the first time.
If poor responses to platelet transfusions are not explained by HLA antibodies, the Blood Service expert provides instructions on further testing (potential HPA antibody tests are carried out by Fimlab Laboratories).
When neonatal alloimmune thrombocytopenia (NAIT) is suspected, a Blood Service physician must be consulted before ordering HPA-typed platelets. All laboratory tests related to NAIT are carried out by Fimlab Laboratories (www.fimlab.fi/hemostaasitutkimukset)