Red Blood Cell Alloimmunization in Korean Patients With Myelodysplastic Syndrome and Liver Cirrhosis

Red Blood Cell Alloimmunization and Its Associated Factors among Chronic Liver Disease Patients in a Teaching Hospital in Northeastern Malaysia

Red blood cell (RBC) alloimmunization is an important complication of blood transfusion. Variations in the frequency of alloimmunization have been noted among different patient populations. We aimed to determine the prevalence of RBC alloimmunization and associated factors among chronic liver disease (CLD) patients in our center. This is a case-control study involving 441 patients with CLD who were being treated at Hospital Universiti Sains Malaysia and subjected to pre-transfusion testing from April 2012 until April 2022. Clinical and laboratory data were retrieved and statistically analyzed. A total of 441 CLD patients were included in our study, with the majority being elderly, with the mean age of patients 57.9 (SD ± 12.1) years old, male (65.1%) and Malays (92.1%). The most common causes of CLD in our center are viral hepatitis (62.1%) and metabolic liver disease (25.4%). Twenty-four patients were reported to have RBC alloimmunization, resulting in an overall prevalence of 5.4%. Higher rates of alloimmunization were seen in females (7.1%) and patients with autoimmune hepatitis (11.1%). Most patients developed a single alloantibody (83.3%). The most common alloantibody identified belonged to the Rh blood group, anti-E (35.7%) and anti-c (14.3%), followed by the MNS blood group, anti-Mia (17.9%). There was no significant factor association of RBC alloimmunization among CLD patients identified. Our center has a low prevalence of RBC alloimmunization among CLD patients. However, the majority of them developed clinically significant RBC alloantibodies, mostly from the Rh blood group. Therefore, phenotype matching for Rh blood groups should be provided for CLD patients requiring blood transfusions in our center to prevent RBC alloimmunization.

A clinical effect of disease-modifying treatment on alloimmunisation in transfused patients with myelodysplastic syndromes: data from a population-based study

BACKGROUND

Alloimmunisation against blood products is an adverse event, causing time-consuming compatibility testing. Current literature has not yet identified the influence of treatment on the risk of alloimmunisation in patients with myelodysplastic syndromes (MDS).

MATERIALS AND METHODS

An observational, population-based study, using the HemoBase registry, was performed including all transfused patients who were diagnosed with MDS between 2005 and 2017 in Friesland, a province in the Netherlands. Information about transfusion dates, types, and treatment regimens was collected from the health records. Blood products were matched for ABO and Rhesus D. The effect of disease-modifying treatment was estimated with incidence rates and a Cox time-dependent analysis.

RESULTS

233 patients were included in this study, with a median follow-up of 13.0 months. Alloimmunisation occurred in 21 patients (9.0%) and predominantly occurred early in follow-up. Three (5%) and 18 (11%) alloimmunisation events occurred in patients with and without disease-modifying treatment, respectively. The hazard ratio for alloimmunisation without treatment compared to during treatment was 2.7 (95% CI: 0.35-20.0), with incidence rates of 7.18 and 2.41 per 100 patient-years, respectively.

DISCUSSION

In a non-selected real-world population of MDS patients receiving blood transfusions, the percentage of patients with alloimmunisation was below 10%. The results of this study support the hypothesis that disease-modifying treatment affects the ability of the immune system to mount an antibody response to non-self blood group antigens.

Red blood cell transfusion in myelodysplastic syndromes: A systematic review

Patients with myelodysplastic syndrome (MDS) frequently receive red blood cell (RBC) transfusions for anaemia resulting from ineffective erythropoiesis. While RBC transfusions may rapidly increase haemoglobin values, their impact on clinical and health services outcomes in MDS patients has not previously been summarized. We conducted a systematic review of the literature to evaluate risks and benefits of RBC transfusions in MDS patients. We searched electronic databases (MEDLINE, Embase, CENTRAL, CINAHL) from inception through June 4, 2021 to identify studies reporting data on RBC transfusions in MDS patients. Full text publications that assessed RBC transfusions as an intervention and reported at least one clinical, laboratory, or healthcare outcome associated with transfusion were included. Study characteristics, transfusion information and transfusion-related outcomes were extracted and reported. We identified 1243 original studies, of which 38 met eligibility requirements and were included. Fourteen reported on survival following diagnosis of MDS, with the majority reporting poorer survival among patients receiving or requiring more frequent transfusions. Nine reported on transfusion-related iron overload and its complications. Other outcomes included rates of allo/autoimmunization and adverse transfusion reactions, and healthcare costs incurred by patients with a greater transfusion burden. Only two studies reported on symptom relief following transfusion. This review underscores transfusion dependence as a negative prognostic factor for MDS patients and highlights the paucity of evidence surrounding quality of life and symptom-related outcomes following RBC transfusions in this population. Further study of patient-important outcomes associated with transfusion in MDS patients is warranted to improve therapeutic recommendations and inform resource allocation.

Blood group antigen and phenotype prevalence in the Korean population compared to other ethnic populations and its association with RBC alloantibody frequency

OBJECTIVES

This study aimed to analyse the allele frequency of blood group antigens in the Korean population and other ethnic populations and the association of blood group antigens with red blood cell (RBC) alloantibodies.

BACKGROUND

Blood group antigen genotyping can support patients undergoing frequent transfusions who have alloantibodies and antibodies against high-prevalence blood group antigens.

METHODS

Twenty-nine single nucleotide variations and 37 blood group antigens were tested. Samples requested for routine blood typing were collected from Jan to Apr 2016. Genotyping was performed on 145 Korean samples and was confirmed by bidirectional sequencing and serologic tests. The allele frequency data were compared with previous genotyping datasets (three datasets from Korea and one each from China, Europe, Asia, and the USA). Alloantibody frequencies and blood group antigens from the electronic medical record of 1772 cases were examined.

RESULTS

E antigen was higher in the Korean population compared to that of Asian and European populations. K, Kp^a , Fy^b and Do^a allele frequencies were lower compared to other ethnic populations. RBC alloantibodies with frequencies (%) greater than 1% from the 1772 cases were as follows: anti-E, 36·7%, anti-C, 17·7%; anti-c 7·39%; anti-M, 5·9%; anti-e, 5·2%; anti-Jk^a , 2·9%; and anti-Fy^a , 1·1%. Blood group antigens and alloantibody frequencies revealed inverse trends that did not reach statistical significance.

CONCLUSION

The allele frequency of blood group antigens assessed by high-throughput methods provided reliable and valuable information that could be used for maintaining donor pools and providing compatible blood for genotyped patients.