Asian Journal of Transfusion Science最新文献

Background: The ABO and Rhesus grouping system antigens have been found to have the highest immunogenicity and propensity to produce alloantibodies that cause most of the transfusion reactions. The Rhesus antigens that produce most of the immunogenic transfusion reactions are D, C, c, E, and e. Knowledge of the distribution of these Rh antigens in a population helps to render compatible blood in alloimmunized patients.

Aim: The aim was to study the distribution and frequency of principal Rh blood group antigens (D, C, c, E, and e) and their phenotypes in the blood donors attending blood bank in a tertiary care hospital in Barpeta district of Assam.

Materials and methods: The study was conducted in 315 voluntary blood donors in the blood bank of a tertiary care center. Rh-D typing was done by conventional tube method. Specific monoclonal antisera, i.e., anti-C, anti-c, anti-E, and anti-e, were used and tests were performed by conventional tube method for detection of the presence of rest of the major Rh antigens.

Results: The samples were analyzed for the five major Rhesus antigens. "D" antigen was found to be the most common antigen (99.05%), followed by e (97.14%), C (92.38%), c (51.43%), and E (20.95%). In order of descending frequency, the most common phenotypes were DCCee - 45.71%, DCcee - 30.48%, DCcEe - 11.43%, DccEe - 4.76%, DCcEE - 1.90%, DCCEe - 1.90%, Dccee - 1.90%, DCCEE - 0.95%, and dccee - 0.95%.

Conclusion: D antigen is the most common antigen in our study population, whereas "e" antigen is the most common in most of the studies done from other parts of India. Data on frequencies of major Rh antigens in the local donor population will help in transfusing alloimmunized patients with corresponding antibody-negative blood ensuring blood safety.

Background: With blood component therapy becoming the standard of care in transfusion medicine globally, the quality control (QC) of these components has become a routine and mandatory program in all blood centers. Extensive utilization of blood components has been observed in our multidisciplinary tertiary care hospital. We use quadruple bag systems and automated component extraction facilities for collection and processing of whole blood (WB). In this study, we analyzed our data relating to QC of all blood components which we prepare and issue for transfusion.

Materials and methods: The retrospective 5-year study comprised 47,430 WB collections which were separated into blood components using quadruple bags and automated component extraction machine. A total of 90 units of WB were processed into blood components for the machine calibration and validation. Routine use of the system was started once the calibration and validation results were acceptable. At least 1% of each component prepared was subjected to QC as per departmental standard operating procedures. Statistical analysis was done using the SPSS statistical package.

Results: The mean volume, hematocrit (Hct), platelet (PLT), and white blood cell (WBC) in 350 and 450 mL WB units were 394.63 mL, 39.43%, 0.93 × 10¹¹, and 3.12 × 10⁹ and 507.75 mL, 40.72%, 1.13 × 10¹¹, and 3.45 × 10⁹, respectively, with mean recovery of PLT and WBC in buffy coat being 95.54% and 68.63% and 97.87% and 74.51%, respectively. As high as 89.91% RBC recovery was noted in the packed red blood cell units which were subjected to QC. QC of random donor platelets was performed in 979 (2.36%) units with acceptable results. The mean fibrinogen and FVIII values were estimated to be 469.17 mg and 217.34 IU (1.07 IU/mL) and 600.21 mg and 273.39 IU (1.11 IU/mL) in fresh frozen plasma units prepared from 350 and 450 mL WB, respectively. A total of 578 (1.62%) units of cryoprecipitate were investigated for QC with favorable results.

Conclusion: We conclude that QC data generated in this study will provide invaluable information about the performance of the latest blood collection systems. QC of all blood components under study complied with both national and international standards. We opine that all blood centers should establish a complete QC program and adhere to departmental protocols and manufacturer's instructions for its execution and effective outcome.

Tuberculosis (TB) has varied manifestations, but autoimmune hemolytic anemia (AIHA) due to TB is rare. Direct antibody test (DAT) or Coombs negative AIHA is also rare. We report a case of a 14-year-old boy who presented with hemolytic anemia and pneumonia. The Coombs test was repeatedly negative. After ruling out the possible infectious and noninfectious causes by extensive investigations, he was diagnosed as DAT-negative AIHA by monospecific antibody test with 4°C low ionic strength saline washes and column agglutination method which revealed the presence of IgG-2+ antibodies. Bronchoalveolar lavage fluid for acid-fast bacilli and gene Xpert was also positive. It is important to recognize TB as a cause of AIHA in South Asian countries where its incidence is high.

The Bombay Rh D negative is the rarest of the rare in blood groups. A 65-year-old male patient with coronary artery disease was admitted for CABG. During grouping, forward showed no agglutination in A, B, D, and H, and reverse showed agglutination in A, B, and O cell. The blood group was confirmed as Bombay Rh D negative. Four units of PRBC was requested for the surgery as it was cardiothoracic surgery. We checked our inventory and rare donor list for Bombay-negative blood. Acute normovolemic hemodilution was done for 2 units preoperatively with saline replacement. Autologous platelet apheresis was done for this patient. During routine cross-match, one unit was incompatible. The patient had naturally occurring anti-S, which was reactive at 37°C and clinically significant. A total of 4 PRBC (Packed Red Blood Cell), 1 Single Donor Platelet (SDP), 12 Fresh Frozen Plasma (FFP), and 9 cryoprecipitate were transfused throughout the hospital stay. The patient was Bombay Rh negative with anti-S with major surgery, which was re-explored twice; the patient was managed successfully in spite of all these difficulties with cooperation from different blood banks from all over India.

Myasthenia with thymoma and parathyroid adenoma is a rare presentation. Very few cases have been reported of this association without much role of plasma exchange in these patients. Here, we present our experience of plasma exchange in this rare clinical entity.

Background: In clinical practice, laboratory results are of great importance for the diagnosis and treatment. Reference intervals of different parameters aid health-care professionals in the interpretation of results. There are very few studies on reference intervals from India. This prospective study was conducted to determine the reference intervals for platelet count (PLT) and PLT indices; mean PLT volume (MPV), PLT distribution width (PDW), and PLT large cell ratio (P-LCR). These values can be obtained as a part of a routine complete blood count (CBC) and have diagnostic and prognostic significance in certain diseases. PLT count is an important criterion for the selection of donors for repeat plateletpheresis donation.

Materials and methods: Sixteen hundred and thirty-four first-time healthy volunteer plateletpheresis donors were enrolled for the study. CBC was done, values of PLT, MPV, PDW, and P-LCR were noted, and the results were analyzed. The 95% of the reference distribution was estimated using the 2.5th and 97.5th percentiles following Clinical and Laboratory Standards Institute guidelines. Adverse donor reactions, if any and quality parameters of single donor PLTs (SDP) were also studied.

Results: Reference range values of PLT, MPV, PDW, and P-LCR were 137,825-355,175/μl, 8.1-13.9/fl, 9.1-22.5/fl, and 11.7%-52.9%, respectively, and compared well with other published studies from India. It was observed that reference values of PLT count obtained in the study were lower than reference values that are currently used in most laboratories (150,000-450,000/μl) in India.

Conclusion: Based on our results, we are of the opinion that the PLT count cutoffs for repeat plateletpheresis donation may need to be revised downwards for our country which would also mitigate the scarcity of apheresis donors.

The Diego (Di) blood group system comprises 22 antigens located on the band 3 protein, most of which are low-prevalence antigens. The majority of antibodies to Diego system antigens were of clinically insignificant; however anti-Dia, -Dib, -Wra, -ELO and-DISK may cause hemolytic disease of the fetus and newborn (HDFN) and transfusion reaction. We reported a case of naturally occurring of anti-Dia in a young man who presented to our hospital for wound debridement of fingers injury. His serological results were suggestive of anti-Dia antibody, and his molecular blood group showed he has Di (a-b+) antigen. Anti-Dia may be clinically significant. It can cause mild-to-severe HDFN, but there are only infrequent reports of it being clearly implicated in a hemolytic transfusion reaction. We suggest the need for reagent red blood cell panels to include Dia antigen-positive cells in antibody identification tests for our populations.

Panagglutination on the indirect antiglobulin test is one of the most challenging dilemmas of pretransfusion testing. It occurs when patient sera react with all red blood cells tested, that is, with both screening and identification panel cells. Two main questions must be answered. The first is to determine whether panagglutination results from the presence of autoantibody and/or alloantibody (single alloantibody or multiple alloantibodies or antibody to high-incidence antigen). The second problem is to detect the possible concomitant presence of clinically significant alloantibodies masked by panagglutination. The purpose of this mini-review is to describe the situations that can cause panagglutination and to develop algorithms which can resolve the problem. The two main points in the evaluation of panagglutination involve the assessment of the intensity of reactivity with the reagent red cells used and whether the autocontrol is positive or not. It is imperative to understand the laboratory results and the techniques available that guide the investigative process.

Background: Regular blood donation depletes iron stores. The assertion is that the vulnerable donor population requires a predictive standard operative procedure for early detection of iron store depletion, preventing them from developing iron-deficiency anemia.

Aim: This study aims to study the potential effects of blood donation in the regular donor group using hematological and biochemical estimation of iron status parameters.

Study settings and design: This was a prospective cross-sectional study on regular blood donors, defined as those who have donated at least 3 times, the last donation being within the last 12 months and continues to donate at least once a year, at a tertiary care teaching hospital in Southern India.

Materials and methods: The complete blood count (CBC) was performed on the Sysmex coulter, and the red cell indices were calculated. The ferritin and the soluble transferrin receptor (sTfR) assays were performed using Enzyme Immunoassays.

Statistical analysis used: The comparison of CBC, serum ferritin, and sTfR assay with donation frequency and time since the last donation was carried out using an independent student's t-test for two groups. The statistical analysis was performed using SPSS for Windows version 20.

Results: A total of 323 regular blood donors (6 were females) were included in the study of which they were categorized into three, 211 donors with less than or equal to 10 donations, 84 those who had donated between 11 and 20 times and 28 who had donated more than 20 times. The red cell indices were reduced and different in the groups but not statistically significant except for mean corpuscular volume. About 15% of the study population had a transferrin level of <15 ng/ml. The Ferritin levels showed a statistically significant negative correlation with the number of donations, the correlation coefficient being -0.27. Logarithmic ratios of sTfR/ferritin also correlated with a coefficient of 0.156 with the number of donations and were statistically significant.

Conclusion: Our study found that regular blood donors had low iron stores, as shown by ferritin levels and other iron indicators. Using the current guidelines (hemoglobin >12.5 g/dL) for donation, or the red cell indices alone do not reflect the donor's actual iron status.