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BACKGROUND: One of the complications of chronic transfusions in thalassemia is the development of red cell alloimmunization. AIMS: The aim of the study was to determine the frequency, specificity of red cell alloantibodies, and factors influencing alloimmunization in multiply transfused thalassemia patients. MATERIALS AND METHODS: The study was carried out prospectively on beta-thalassemia patients over 10 months. Plasma samples were used for antibody screening and identification using the column agglutination technique. Patients' clinical, laboratory, and transfusion details were obtained from hospital information system and patient files. STATISTICAL ANALYSIS: Continuous variables were reported as median and quartile, whereas categorical variables were provided as numbers and proportions. P < 0.05 was considered statistically significant. RESULTS: Out of 255 patients, 17 (6.6%) patients developed alloantibodies. Alloimmunized patients had significantly higher median ages at their first transfusions (1 year vs. 0.5 years; P = 0.042) than nonalloimmunized patients. Alloimmunized patients had significantly higher conjugated bilirubin (P = 0.016) and serum ferritin (P = 0.007). The majority of alloantibodies had specificity toward K antigen, followed by E, C, D, JKa, and JKb antigens. Alloimmunized patients received more units per year than nonalloimmunized patients (median, 30 vs. 24 units; P < 0.001). The average transfusion interval time between two successive transfusions showed a significant difference (P < 0.001). CONCLUSIONS: The prevalence of alloimmunization in thalassemia patients in North India is relatively low. Since most of the alloantibodies belong to Rh and Kell blood group system, extended phenotype-matched blood for Rh and Kell will be helpful in further preventing or decreasing the development of alloantibodies in multiply transfused thalassemia patients. [ABSTRACT FROM AUTHOR]

Objective This study was conducted to estimate prevalence of direct antiglobulin test (DAT) positivity and its impact on transfusion support in patients with thalassemia. Methods The DAT testing was performed for patients with β-thalassemia who received transfusion from November 2021 to March 2022. Elution was done for DAT-positive samples. Results Of 180 patients, 21 (11.6%) were DAT positive. Immunoglobulin G (IgG) was present in 4 (19%) and IgG+C3d was present in 8 (38%). Only complement was present in 9 (42.8%) patients. The IgG-reactive DATs were associated with pan-reactive eluate. Patients who were DAT-positive had significantly higher levels of serum bilirubin, ferritin, and IgG than those who were DAT-negative. Conclusion Autoantibody formation in multiply transfused thalassemia patients is common and merits equal attention as alloimmunization. It is particularly important as DAT-positive red blood cells may undergo clinically significant hemolysis, which may increase the transfusion requirements with associated sequalae such as increased serum ferritin and splenomegaly. [ABSTRACT FROM AUTHOR]

The widespread use of anti-D immunoglobulin has resulted in a relative increase in the importance of non-D alloimmunization as a cause of hemolytic disease of the fetus and newborn (HDFN). Non-D alloantibodies that are capable of causing severe HDFN include anti-K, anti-E, and anti-c. Anti-c is clinically the most important Rh system antibody after anti-D. Here, we report three cases of neonates presenting with anemia and hyperbilirubinemia with strongly positive direct antiglobulin test who required phototherapy and neonatal exchange transfusion due to non-D antibody in RhD positive antenatal women. Anti-c was common in all the three cases while two cases have one additional non-D antibody. Due to faulty practices, antenatal antibody screening was not done for any case considering the mother's RhD positive status. Hence, antenatal antibody screening should be performed routinely, in all RhD positive pregnant women to reduce the delay in diagnosis and the management of HDFN occurring due to non-D antibodies. [ABSTRACT FROM AUTHOR]

Background: Direct antiglobulin test (DAT) is the most common test done in immunohematology lab, which detects immunoglobulin and fragments of complement attached to the red blood cells. These coated red blood cells are difficult to accurately phenotype, which may be required for selection of appropriate unit of red blood cells for transfusion. Aims: We have studied the efficacy of various elution methods in removing the antibodies coating the red cells and their impact on different blood group antigen activity. Materials and Methods: Patient samples sent for serological evaluation of autoimmune hemolysis were included in the study. DAT and Indirect antiglobulin test (IAT) were performed using gel cards (ID system, DiaMed Switzerland). Antibody coated red cells, either by in-vivo or in-vitro sensitization, were used to assess the outcome of three elution methods. Results: Out of 93 DAT positive samples already sensitized in vivo, 28 (30 %) samples became DAT negative post elution using either of three methods, while 36 (38.8%) showed reduction in strength of reaction, whereas in 29 (31.2%) there was no change in strength of reaction. Similarly, out of the 17 samples prepared by in vitro sensitization, 12 samples became completely negative after glycine-HCl/EDTA elution, 9 and 5 samples became negative after heat elution and chloroquine diphosphate elution methods, respectively. Conclusion: On comparative analysis glycine-HCl/EDTA elution method was better than the other two methods and can be used for eluting immunoglobulins from intact red cells. [ABSTRACT FROM AUTHOR]

Clinical and serological characterization of autoimmune hemolytic anemia (AIHA) helps in the diagnosis, management, and monitoring course of disease. In the present study, we serologically characterized the red-cell-bound autoantibodies in diagnosed AIHA patients with regards to antibody class, subclass, direct antiglobulin test (DAT) strength, and their correlation with in vivo hemolysis. A total of 157 samples were evaluated for DAT. Clinically and serologically, 43 of them were diagnosed as AIHA. Detailed serological characterization of autoantibodies was performed in these 43 patients using the gel technology. Hematological and biochemical parameters were obtained from the Hospital Information System. Polyspecific (immunoglobulin G (IgG) + C3) DAT-positive samples were tested for monospecific DAT (IgG, IgM, IgA, C3c, and C3d) and IgG subclass (IgG1 and IgG3). Thermal amplitude of autoantibodies was determined on eluates. Median age of the patients was 31 years (range, 12–70 years) with male to female ratio of 1:3.3. In 55.8% of patients, AIHA was secondary to an underlying disorder. Patients with strong reactive DAT had increased likelihood of hemolysis ( p = 0.000). IgG was the solitary autoantibody coating the red cells in 72.1% of patients. Red cells coated with multiple immunoglobulins/complements and IgG subclass IgG1 and/or IgG3 were more susceptible to undergo hemolysis. Gel technology helps the immunohematologist to diagnose and serologically characterize AIHA patient with regard to red-cell-bound autoantibodies’ class, subclass, and titer as these correlate with in vivo hemolysis. [ABSTRACT FROM AUTHOR]

Coombs negative autoimmune hemolytic anemia (AIHA) is characterized by laboratory evidence of in vivo hemolysis along with a negative direct antiglobulin test (DAT) performed by conventional tube technique (CTT) in clinically suspected AIHA patients. The sensitive gel test (GT) and flow cytometry (FC) can effectively diagnose such patients where CTT does not detect low level of red cell autoantibodies. We investigated the use of FC in the serological evaluation of CTT DAT negative AIHA and its comparison with GT DAT. Of the 50 patients with suspected AIHA, CTT DAT was negative in 5 patients (Coombs negative AIHA). GT DAT could detect red cell autoantibodies in 4 of these 5 patients. Monospecific GT DAT showed IgG and/or C3d as the responsible autoantibody. FC was considered as reactive when MFI was >3.6 (mean of 20 healthy negative volunteers +2SD). FC was reactive in all five Coombs negative AIHA patients. The mean MFI in five known CTT DAT positive samples taken for comparison was significantly higher compared to 5 DAT negative AIHA (18.3 ± 7.78 vs. 7.88 ± 1.35, p < 0.05). There was poor correlation between strength of GT DAT and MFI by FC. We conclude that FC is more sensitive test than the CTT and helps in the serological diagnosis of Coombs negative AIHA. However, in resource poor settings, GT DAT can be a good alternative to FC. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the incidence of red cell alloimmunization in India, the development of antibodies on patients with chronically transfused thalassemia, and the complications of transfusion therapy.

Immune hemolysis is one of the adverse effects that can occur following solid organ transplantation. Understanding the clinical settings and the various causes is necessary for prompt diagnosis and appropriate management. One such condition is passenger lymphocyte syndrome (PLS). This case report describes the case of a 27-year-old male renal allograft recipient of the B-positive blood group who received a kidney from an O-positive donor. Postoperatively, the patient showed declining hemoglobin (Hb) level and was transfused with B-group packed RBCs (PRBCs), following which there was steep fall in Hb level. A request for PRBCs was sent to the blood bank and this time cross-match with B-group PRBCs showed incompatibility. The patient's RBCs were found to be strongly DAT (direct anti-globulin test) positive and the eluate showed the presence of anti-B with a titer of 32. Thus, diagnosis of probable PLS was made. The patient was managed with methylprednisolone, plasmapheresis and O-group PRBCs. Gradually his condition improved and was discharged in stable condition. [ABSTRACT FROM AUTHOR]

Abstract: Background: Alloanti-Kpb is a rare, clinically significant antibody against high frequency red cell antigen Kpb of Kell blood group system. We report here a case of Haemolytic disease of newborn (HDN) due to anti-Kpb, which manifested as severe anaemia at the age of 1 month. Aim: To diagnose and successfully manage anti-Kpb induced HDN. Methodology: Direct antiglobulin test (DAT), antigen typing, irregular antibody screening and identification were done by polyspecific LISS Coombs Gel card and standard methods. Results: At presentation the neonate had severe anemia with reticulocytopenia. Blood group was B, Rh D positive and DAT was 2+. Anti-Kpb was detected in mother’s serum. Due to unavailability of Kpb negative red cells and incompatible blood group of mother (A1B Rh D positive) infant was transfused group B Rh D, Kpb positive PRBCs under steroid cover. He was symptom free at 4 months of age and DAT became negative at 6 months. Conclusion: Anti-Kpb is capable of causing severe late HDN. Infants born to irregular antibody positive mothers should be investigated and closely monitored for several weeks after birth for immune HDN even if asymptomatic at birth. [Copyright &y& Elsevier]

Abstract: Introduction: Transfusion transmitted Toxoplasma gondii (T. gondii) can result in significant clinical consequences in immunocompromised and multiply transfused patients, pregnant women and fetus etc. Anti-T. gondii seroprevalence, specifically IgM antibodies reflect the risk of transfusion transmission. Methods: Four hundred and ninety-three blood donors in a tertiary care hospital in North India were screened for IgG and IgM anti-T. gondii antibodies by enzyme linked immunosorbent assay (ELISA). Results: The prevalence of IgG and IgM anti-T. gondii antibodies was 51.8% and 5% respectively. The prevalence was higher in females (M=51.6%, F=89.2%) and in replacement donors (replacement donors=63.2%, voluntary donors=33.5%). Conclusion: The donor population constitutes a significant risk of transfusion transmitted toxoplasmosis. Effective strategies are required to prevent transfusion transmitted toxoplasmosis. [ABSTRACT FROM AUTHOR]

Abstract: ABO discrepancy refers to incongruence between the results of red cell and serum groupings. One such case is described here; the discrepant results of whose routine ABO grouping led to the diagnosis of common variable immunodeficiency. There was no reaction in the reverse grouping of a young patient presenting with recurrent bacterial infections, pointing towards an absence of antibodies in the serum. Diagnosis was made on the basis of markedly decreased serum immunoglobulin levels and by serum protein electrophoresis showing scanty gamma regions. [Copyright &y& Elsevier]