RESUMEN
BACKGROUND: In Vietnam, a lack of evidence about the unexpected antibodies hinders the capabilities to prepare the necessary resources and personnel for treating patients with blood disorders. This study aimed to measure the rates of different unexpected antibodies in patients having blood orders in Vietnam. STUDY DESIGN AND METHODS: A cross-sectional study was conducted at the National Institute of Hematology - Blood Transfusion, Vietnam on 5608 patients with blood disorders. Information was obtained from the medical records, blood transfusion forms, screening test forms. RESULTS: The prevalence rate of unexpected antibodies in patients with haematological disorders was 9.3%. The most prevalent occurrence was the presence of an atypical antibody type, accounting for 61% of patients. The co-occurrence of this atypical antibody type and other types of antibodies was also observed, with the respective occurrence rates of 23.9%, 10.1%, 3.8%, and 1.2% for the combination of two, three, four, and five unexpected antibody types. The presence of one type of unexpected antibody was predominant, namely anti-E, accounting for the highest proportion (32.9%), followed by anti-Mia (18.4%). Among the 125 patients, the most frequently observed combination of abnormal antibodies was anti-E with anti-c (14.3%) and anti-E with anti-Mia (3.4%). Among the cohort of 53 patients exhibiting three types of unexpected antibodies, the most prevalent combination observed was anti-c, anti-E, and anti-Mia (5.7%). CONCLUSION: This study revealed a prevalence rate of 9.3% in the presence of unexpected antibodies in patients with blood disorders. The occurrence of individual unexpected antibodies surpasses that of coordinated antibodies.