Prevalence of unexpected red blood cell antibodies in pregnant women and follow-up of pregnancy outcome in pregnant women treated with intra-uterine transfusion.

BACKGROUND: For the management of hemolytic disease of the fetus and newborn (HDFN), it is important to detect unexpected red cell antibody in pregnant women. We assessed the prevalence of unexpected red cell antibodies in consecutive pregnant women attending antenatal clinic (ANC). More importantly, cases with unexpected antibody causing severe anemia were followed-up for intervention (Intra-uterine transfusion {IUT}) and outcome of pregnancy (still-birth/live-healthy). AIMS AND OBJECTIVES: The study was conducted with an objective to find the prevalence of unexpected RBC antibodies in pregnant women, their specificity and to do the follow-up for IUT and outcome of pregnancy (still-birth, live-birth) in antibody positive women. MATERIALS AND METHODS: This was a prospective study from January 2021 to May 2022 at two tertiary care centres. All antenatal samples received by the laboratory were screened for unexpected red cell antibody. Whenever antibody screen was positive, antibody identification was performed. Patients, positive for unexpected antibody and anemia were followed up for any transfusion-based intervention and outcome of pregnancy. RESULTS: A total of 539 consecutive samples were worked up and among these, 10 samples (1.85%) were found to be antibody positive. The antibodies identified were Anti-D (n=6), anti-Leb (n=1), anti-M (n=1), anti-C (n=1) and anti-E (n=1).The prevalence of unexpected antibodies in Rh positive and Rh negative pregnant women was 0.83% and 10.9% respectively. Follow-up was done for all 10 cases with unexpected antibody and anemia was monitored by MCA PSV (middle cerebral artery peak systolic velocity).Two women developed severe anemia thus requiring single intrauterine transfusion (at 26 weeks and 28 weeks respectively) each, for correction of anemia. In both these cases, healthy male child was delivered. At 3-month follow-up both children were alive and healthy. CONCLUSION: The study found prevalence of unexpected RBC antibodies in pregnant women as 1.85%. The study also underlined importance of transfusion-based interventions contributing to successful outcome in couple of cases with severe anemia.

A patient with anti-f in India identified by extensive immunohematologic workup.

Anti-f is produced by exposure to the compound antigen ce (f) on red blood cells (RBCs), expressed when both c and e are present on the same protein (cis position). Although anti-f was discovered in 1953, there are few cases reported worldwide because the presence of anti-f is often masked by anti-c or anti-e and is not generally found as a single antibody. In the present case, anti-f was identified by using three-cell screening and 11-cell identification panels. The identification of anti-f was further supported by additional testing, including (1) Rh antigen typing; (2) antibody identification panels (enzyme-treated panel [ficin] and an in-house-constructed Rh panel); (3) look-back and phenotyping of donor RBC units, which were responsible for alloimmunization; and (4) molecular testing of the patient's RBCs.

Determination of optimum levels of binding antibody units (BAU) of new quantitative chemiluminescent immuno-assay (CLIA) in COVID-19 vaccinated volunteer blood donors.

BACKGROUND: For assessment of COVID-19 vaccine efficacy, neutralization activity of anti-SARS-CoV-2 antibody is measured. This study was undertaken to determine optimum levels of binding antibody units (BAU/ml) in new quantitative chemiluminescent assay (CLIA) that corresponded to neutralizing potential (30% inhibition) of sVNT assay. METHODS: Ninety-one blood samples were analyzed by CLIA and sVNT assays. Test samples (n = 75) were collected from blood donors post-2nd vaccination dose, while control samples (n = 16) were archived pre-COVID donor samples. Correlation between CLIA and sVNT was calculated and receiver operating characteristic (ROC) curve was drawn and analyzed. RESULTS: Results indicated excellent correlation between 57.5 BAU/ml on CLIA and 30%inhibition on sVNT assay. ROC curve analysis revealed that the area under the curve (AUC) was 0.971. DISCUSSION: The present study determined that 57.5 BAU/ml on CLIA corresponded to 30% inhibition on sVNT assay. Periodic quantitative analysis.

I-JAMM-(I): A survey providing an insight into the practices of isoagglutinin titration in ABO incompatible kidney and liver transplantation.

BACKGROUND AND OBJECTIVES: ABO-incompatible transplantations allow patients to receive timely transplants. Isoagglutinin titration to ascertain levels of incompatible antibodies in the recipient is important in determining patient selection and transplant survivability. To find out the prevalent trends in India, the largest, first of its kind survey was carried out among the transplant centers regarding their practices in isoagglutinin titration. METHODS: The survey was drafted by a working group of Transfusion and Transplant Immunology specialists from six different centers. Data was obtained via the use of an online questionnaire. RESULTS: Results were categorized into four categories, Hospital information, Titration methodology, Role of transfusion specialists and cut-off titers. Most centers had a well-established solid-organ transplant program with considerable number of ABO-incompatible transplantations. Most centers performed isoagglutinin titration in Transfusion Medicine department. Column Agglutination Technique (CAT) was the most common method, using EDTA blood samples and freshly-prepared in-house pooled cells. Most centers had a turn-around time of less than 12 h. While the policy for ascertaining baseline and threshold titers is well-defined in ABO-incompatible renal transplants, variations from center to center still exist for ABO-incompatible liver transplants. Most centers required a Transfusion Medicine consultation for the patients before such transplants. CONCLUSION: With increasing ABO-incompatible kidney and liver transplants across the country, the role of Transfusion medicine specialists has become vital in pre-conditioning regimes enabling the viability and success of such transplants. This was a unique survey that provided a snapshot of current trends and practices of isoagglutinin titration for ABO-incompatible transplants in India.

Anti-G with Concomitant Anti-D and Anti-C in a Pre-natal Patient, in India: Multi-disciplinary Approach to Diagnosis and Management.

'G' antigen belongs to the Rh family and it was first described by Allen and Tippet in 1958. Various anti-D, anti-C, and anti-G antibody combinations can be found in patients. Ruling out the presence of anti-D is important for administering RhIg prophylaxis in RhD-negative pregnant women to prevent hemolytic disease of fetus and newborn (HDFN). RhIg prophylaxis is not indicated in the presence of an anti-D antibody. Time-to-time monitoring and follow-up of cases of RhD-negative pregnant women with a multi-disciplinary approach including an obstetrician, neonatologist, and transfusion medicine specialist helps diagnose, manage, and monitor HDFN in such cases. This case report emphasizes the need for proper antibody identification (anti-G) and managing HDFN (with intrauterine transfusions and exchange transfusion) during the perinatal period.

Implementation of an international barcode labeling standard, International Society of Blood Transfusion 128, and its integration with local regulations at a blood center in India: Step-by-step journey.

The International Society of Blood Transfusion (ISBT) 128 is an internationally endorsed, electronically readable labeling standard that provides a convenient and accurate means of identification, traceability, publication, and storage of information for blood and blood products. The authors' center recently registered with the International Council for Commonality in Blood Banking Automation (ICCBBA) and progressed to ISBT 128 labeling standard. This manuscript was written with the objective of sharing the authors' experience with respect to the implementation of ISBT 128 standards for whole blood donations and integration of ISBT 128 standards with Indian licensing regulations. The authors explore the process of implementation of ISBT 128 standards through a step-by-step journey that included facility registration with International Council for Commonality in Blood Banking Automation (ICCBBA), allotment of facility identification number, development of four-quadrant label for blood components, and integration of local regulatory requirements in the final "composite" label. Acknowledging the lack of any published report from India on ISBT 128 standards implementation, the authors wish to attempt help their peers in understanding and implementation of this global standard at their respective facilities.

Analytical and clinical performance evaluation of enhanced chemiluminescence-based fourth-generation HIV combo assay: Report from tertiary health-care setup in North India.

INTRODUCTION: HIV fourth-generation assay, designed for the detection of HIV p24 antigen along with anti-HIV antibodies of both immunoglobulin M and immunoglobulin G type against HIV 1 and HIV 2 viral antigens, have helped in the early detection of HIV infection and supports in minimizing the transmission risk in the acute phase of infection. The objective of this study was to evaluate the analytical and clinical performance of HIV fourth-generation assay based on enhanced chemiluminescence technology. MATERIALS AND METHODS: The analytical performance of the assay was evaluated in terms of accuracy, precision, limit of detection, type of sample (serum vs. plasma), cross-reactivity (with other transfusion transmissible infections markers), and interference (with endogenous substances). Proficiency control material included kit-controls, archived known positive donor samples, third-party controls, and World Health Organization (WHO)/National Institute for Biological Standards and Controls (NIBSC, MHRA, UK) controls. The clinical performance was evaluated using routine donor and patient samples received during the study period. RESULTS: HIV fourth-generation assay showed reliable and reproducible results measured in terms of coefficient of variation % with kit-controls, archived known positive donor samples, third-party controls, and WHO international standards for anti-HIV 1 and 2 antibodies, HIV1 p24 antigens and HIV2 p26 antigen controls. The analytical sensitivity of the HIV fourth-generation assay was found to be 0.1 IU/mL of HIV1 p24 antigen control and there was no cross-reactivity or interference observed. In the clinical performance of the assay, HIV fourth-generation assay showed reliable performance in both donor and patient samples. CONCLUSION: HIV fourth-generation assay meets the requirements for its use as a screening assay for HIV infection based on the analytical and clinical performance of the assay.

Correlation of various methods of hematopoietic progenitor cell estimation with standard flowcytometric CD34 enumeration.

BACKGROUND AND OBJECTIVES: Enumeration of hematopoietic progenitor cell (HPC) is vital to decide the time to initiate harvest (TTIH) and adequacy of harvest dose (AOHD). Standard of care used for HPC enumeration is flowcytometric CD34+ enumeration, but it is expensive, time-consuming and requires skilled staff to perform the test. Alternatively, HPC-count by advanced automated cell analyzer is cheaper, quicker, and easy-to-perform test. Our objective was to find a correlation of HPC count with CD34+ enumeration in leukapheresis. MATERIALS AND METHODS: An observational, prospective study was conducted in the year 2018-2019. A total of 126 samples were included in the study, the peripheral blood (PB) group comprised of 42samples and apheresis group of 84 samples. The samples were simultaneously tested for CD34+ expression and complete blood count which included the HPC count, white blood cells (WBC) count and multinational corporation (MNC) count and correlation analysis was performed with CD34+ flowcytometric count. The cut-off of PB HPC count for the target dose of 5 × 106 CD34+ cells/kg was established using Receiver Operator Curve. RESULTS: The correlation coefficient (r) of HPC with CD34+ count was 0.617 and 0.699 for PB group and apheresis group sample respectively, which was statistically significant. The correlation with MNC and WBC count was not very significant. A cut-off value of PB HPC was established to be 66 HPC/µl with a positive predictive value of 94.12%. The cost of CD34 + flow cytometric enumeration was six times that of HPC enumeration by analyzer. CONCLUSION: The HPC count is a cheaper, rapid and easy test and can be clinically applied to predict TTIH and AOHD but requires more studies to validate its efficacy in clinical use.