Delayed hemolytic transfusion reaction in the French hemovigilance system.

In France, reporting of adverse events related, or likely to be related, to transfusion is mandatory. Since its creation in 1993, the French hemovigilance system has contributed to a better recognition of unappreciated risks like delayed hemolytic transfusion reactions (DHTR) in sickle-cell disease (SCD) patients. Long under-reported or misclassified, reports of this serious complication of transfusion have improved, particularly through the dissemination of information within the hemovigilance network. To our knowledge, the French hemovigilance system has one of the largest series of DHTR in SCD patients. Guidelines for diagnosis and reporting to hemovigilance system as well as a specific reporting form are being developed, which should contribute to the quality of data essential for epidemiological studies.