Antibodies In Donors Research Articles

Prevalence of Antibodies to Hepatitis B Core Antigen in Hepatitis B Surface Antigen Negative Healthy Blood Donors

The screening of HBsAg has been the cornerstone in HBV research in various states and has greatly decreased but not eradicated TAHBV. Anti-HBc was supposed to be a good indicator of latent HBV infection in the window after HBsAg disappeared. Objective: To determine the prevalence of hepatitis B core antibodies in hepatitis B negative surface antigen healthy blood donors. Methods: This Cross-sectional study was held in the Medical Ward 7 of Jinnah Postgraduate Medical Center, Karachi from July 17, 2020 - January 16, 2021. A total of 147 healthy blood donors of both sexes, aged 17 to 65 years, who submitted an application for blood donation, were selected. The venous blood (5 ml) was gathered using aseptic technique. For 5 mints; Sera was centrifuged at 3000 rpm and separated. For the qualitative and quantitative detection of anti-HBc IgM, an ELISA test by DIA was performed. Results: Of the 147 patients, 81 (55.10%) were male, 66 (44.90%) were females with a M: F ratio of 1.3: 1. In this study; the patients age range was 17-65 years with 41.45 ± 8.97 years of mean age. The pervasiveness of anti-hepatitis B antibodies in healthy donors of blood who have negative surface antigen of hepatitis B virus was 6.12%. Conclusions: It was found that the pervasiveness of anti-hepatitis B antibodies in healthy donors of blood who have negative surface antigen of hepatitis B virus was 6.12%.

Prevalence of Hepatitis B Core Antibody in Sudanese Random Blood Donors at Khartoum state, 2022

Background: Hepatitis B virus is a DNA virus belonging to the Hepadnaviridae family attacking the liver and can cause both acute and chronic disease. The aim of this study was to determine the prevalence of Hepatitis B core antibody in Sudanese random blood donors.
 Materials and methods: The study was descriptive cross-sectional study conducted at Ibn Sina Specialized Hospital, Khartoum, Sudan during the period from May 2022 to September 2022. Blood samples were collected from 100 random blood donors. A total of three ml of whole blood were collected from each participant in plain tube. Hepatitis B core antibody test was done by using biochemistry analyzer (Cobas 411).
 Results: The results of this study revealed that all blood donors were negative for HBsAg but 51% of them were positive for HBcAb. The mean average of hepatitis B core antibody in blood donors was 0.984 ± 0.950, where the mean average of hepatitis B surface antigen was 0.685± 0.170. The educational background had a positive correlation with the prevalence of hepatitis B core antibody.
 Conclusion: This study concluded that the prevalence of hepatitis B core antibody in blood donors was high.
 Keywords: Hepatitis B virus infection, hepatitis B core antibody, enzyme linked immunosorbent assay, blood donation, blood transfusion, random blood donors

SARS-CoV-2 Seroprevalence among Canadian Blood Donors: The Advance of Omicron.

With the emergence of the SARS-CoV-2 Omicron variant in late 2021, Canadian public health case/contact testing was scaled back due to high infection rates with milder symptoms in a highly vaccinated population. We monitored the seroprevalence of SARS-CoV-2 nucleocapsid (anti-N) and spike protein (anti-S) antibodies in blood donors across Canada from September 2021 to June 2022 in 202,123 randomly selected samples. Multivariable logistic regression of anti-N positivity with month, age, sex, racialization, region, material and social deprivation (based on postal code) identified as independent predictors. Piece-wise logistic regression analysed the association between anti-S concentration and month, and anti-N/anti-S positivity. Infection-related seroprevalence (anti-N positive) was 4.38% (95% CI: 3.96, 4.81) in September reaching 50.70% (50.15, 52.16) in June; nearly 100% were anti-S positive throughout. Anti-N positivity was associated with younger age, male sex, the Alberta and Prairies regions, greater material deprivation and less social deprivation (p < 0.001). Anti-S concentration was high initially (3306 U/mL, IQR 4280 U/mL), increased to (13,659 U/mL, IQR 28,224 U/mL) by June (p < 0.001), following the pattern of deployment of the third and fourth vaccine doses and was higher in those that were anti-N positive (p < 0.001). Despite already high vaccination-related seroprevalence, infection-related seroprevalence increased dramatically with the emergence of the Omicron SARS-CoV-2 variant.

Presence of antibodies against HLA class I and class II molecules in children before and after allo-HSCT. Alloantibodies before and after HSCT.

A severe complication of allogeneic hematopoietic stem cell transplantation (HSCT) is graft failure (GF). Among others, donor-specific anti-HLA antibodies (DSA) are associated with graft rejection after allogeneic or haploidentical transplantation in adults. Knowledge of DSA and pediatric recipients is limited. Hence, we aimed to generate more information about the presence of DSA (pre- and post-HSCT) and the clinical outcomes (graft rejection and poor function) in children. We identified DSA in 27% of the patients. We observed a higher frequency (50%) of DSA-bearing patients with a benign disease diagnosis than those diagnosed with leukemia (16.66%). We observed graft rejection in one patient (with DSA against two alleles of HLA class I molecules) and poor function in three recipients during the first 30 days after HSCT in the absence of DSA. The presence of donor and nondonor HLA-specific antibodies decreased substantially after transplantation. After the transplant, we identified two patients with DSA specific for HLA class I molecules (independent of clinical relevance), and four recipients showed PGF in the absence of DSA. We were unable to establish any association between the presence of DSA and a clinical outcome: graft failure or prevalence of viral infection.

Blood and Blood Products to Support Allogeneic Hematopoietic Progenitor Cell Transplant Recipients at King Abdulaziz Medical City-Riyadh – Transfusion Medicine Services

Hematopoietic progenitor cell transplant (HPCT) is found throughout the body. HPCT is a set of undifferentiated cells that are capable of indefinite self-renewal and generation of a functional progeny of highly specialized cells. Allogeneic HPCT presents a distinct set of challenges for blood banks and transfusion services. When considering transfusion for an HPCT recipient, one has to take into account not only the complexities associated with the patient's underlying condition, but also potential problems associated with recipient alloantibodies, donor passenger lymphocytes, and the conversion of blood group substance after successful allogeneic HPCT. For an allogeneic HPCT recipient, it is vital that the blood transfusion service keep a detailed record of the donor and recipient's that include donor blood group and antibody screening results and recipient's pre- and posttransplant blood group and antibody screening results. The management of nonidentical and incompatible HPCT requires a unique strategies when major, minor, and bidirectional differences exist which have the potentiality to improve patient outcomes and allow for effective management of the blood and blood products inventory.

Toxoplasmosis Immunity Status of Blood Donors in Sidi Bel Abbès, West Algeria.

BackgroundToxoplasmosis is a zoonotic disease. It is due to an obligate intracellular protozoan called Toxoplasma gondii (T. gondii). Felids are considered definitive hosts, and humans take part as intermediate hosts. At least one-third of the world’s population is seropositive to the parasite. In addition, to the known modes of transmission, the infection can be transmitted through blood transfusions. The aim of this study is to assess the immune status of blood donors about this disease and estimate the potential risk by blood components.MethodologyA single cross-sectional study was conducted based on the search for T. gondii antibodies (IgG and IgM) in blood donors. This research was performed using a latex particle agglutination assay confirmed by an enzyme-linked immunosorbent assay (ELISA).ResultsIn all, 103 blood donors were involved in this study. The sex ratio of male/ female was 0.75. The recorded rate of exposure to toxoplasmosis in blood donors was 47.7% (95% CI: 35.1-54.3). Significant differences were observed between the prevalence and those of other African countries in West, East, and Central Africa, but not with those of Algerian pregnant women and neighboring North African countries. There was no association between T. gondii seropositivity and the following factors: sex, age, and blood group ABO or Rhesus. Antitoxoplasma IgG was detectable in all positive donors, while IgM was undetectable. All seropositive donors had an IgG titer ≥9 IU/ml. The potential risk of T. gondii transmission ranges from 1 per 100,000 to 17 per 100,000 blood donations.ConclusionThe seroprevalence of T. gondii infection was comparable to those found in Algerian pregnant women and neighboring North African countries. However, the seroprevalence rate was lower than recorded in other African countries. There is even a risk of transmission of toxoplasmosis through blood transfusions. There is a need to enhance blood safety measures for pregnant, immunocompromised, and multi-transfused people. As the immune status of blood donors may vary by region, there is a need to extend the national studies to the entire country. This study provides the first data on the seroprevalence of T. gondii infection among Algerian blood donors and the risk of its transmission by transfusion of blood components.

Investigation of Anti-B19V IgM Antibodies Seroprevalence among Blood Donors in a Blood Transfusion Center in Diyala Governorate, Iraq

Introduction: Parvovirus B19 [B19V] is a small DNA virus characterized by global circulation, the route of transmission of this virus through blood and its products has alarming health dimensions, especially for recipients who have medical conditions that require blood transfusion. Objectives: This study aims to enhance the safety of blood transfused to recipients by investigating the seroprevalence of B19V IgM antibodies in donors' blood. Methodology: One hundred and eighty-eight blood samples from donors were collected from the blood transfusion center (blood bank) in Diyala Governorate, Iraq, from both sexes, and using ELISA technique, the seroprevalence rate of B19V IgM antibodies was determined. Results: Anti-B19V IgM was detected in 11.2% (21/188) of the blood donor samples tested, the highest prevalence of anti-B19V IgM antibodies appeared among the age group 30–39. Male participants in this study showed a higher prevalence of IgM antibody to B19V compared to females. This study showed the presence of co-infections between B19V and hepatitis B Core, the serological test showed that 2 (22%) of the cases positive for the B19V IgM antibodies were also positive for the anti-HBC total Antibodies. Conclusion: The current study concludes that the seroprevalence of B19V IgM antibodies among blood donors is high, and poses a risk to sero-negative recipients who have healthy conditions and need blood transfusions. There is a need to conduct more future studies with a large sample size at the serological and molecular levels in cooperation and support provided by the health institutions in the country.

Convalescent Plasma for COVID-19: A Single Center Prospective Experience with Serial Antibody Measurements and Review of the Literature.

Background: High-titer convalescent plasma given early for COVID-19 may decrease progression into a severe infection. Here, we reported a study of serial antibody measurements in patients who received CP at our center and performed a systematic review of randomized trials on CP. Methods: Our center participated in the Mayo Clinic Expanded Access Program for COVID-19 Convalescent Plasma. Patients diagnosed with COVID-19 by nasopharyngeal polymerase chain reaction at our center between April and August 2020 were included in the study if staffing was available for specimen collection. Through a colloidal gold immunochromatography assay, these patients’ IgM and IgG antibody responses were measured at baseline (Day 0) and after transfusion (Day 1, 2, etc.). Donor CP antibody levels were measured as well. Results: 110 serum specimens were obtained from 21 COVID-19 patients, 16 of whom received CP. The median time from developing symptoms to receiving CP was 11 days (range 4–21). In 9 of 14 (64%) cases where both recipient and donor CP antibody levels were tested, donor COVID-19 IgG was lower than that of the recipient. Higher donor antibody levels compared with the recipient (R = 0.71, p < 0.01) and low patient IgG before CP transfusion (p = 0.0108) correlated with increasing patient IgG levels from baseline to Day 1. Among all patients, an increased COVID-19 IgG in the short-term and longitudinally was positively correlated with improved clinical outcomes (ρ = 0.69, p = 0.003 and ρ = 0.58, p < 0.006, respectively). Conclusions: In a real-world setting where donor CP was not screened for the presence of antibodies, CP in donors might have less COVID-19 IgG than in recipients. An increase in patient antibody levels in the short term and longitudinally was associated with improved clinical outcomes.

Prevalence of Treponema Pallidum Antibody among Volunteer Blood Donors in China.

Background Infection with syphilis is still a major public health problem. The precise data for syphilis seroprevalence in the populations will help to develop a strategy for prevention and treatment of it. However, the data for syphilis prevalence in continuous years among volunteer blood donors in China is rare. Methods A retrospective study for Treponema pallidum (TP) antibody in blood donors was conducted from January 2010 to December 2019 at the Blood Center of Zhejiang Province, China. TP antibody was detected with two different reagents using enzyme-linked immunosorbent assay and the only sample which was reactive in the two reagents was defined as seropositive. Results A total of 992,646 volunteer blood donors were analyzed and the positive rate of TP antibody in the blood donors was 0.43%. From 2010 to 2019, the positive rates of TP antibody were 0.53%, 0.51%, 0.51%, 0.43%, 0.36%, 0.18%, 0.11%, 0.12%, 0.11%, and 0.10%, respectively. The positive rates of TP antibody were significantly different among blood donor age group (p < 0.001), with the highest positive rate in 45–54-years-old group (0.93%). The positive rates of TP antibody in male and female blood donors were 0.44% and 0.41%, respectively. The positive rate was 0.57% among the first-time blood donors, which was significantly higher than that of the repeat blood donors (0.17%). The positive rate of TP antibody in blood donors decreased gradually with the increase of educational level. Conclusion The syphilis seroprevalence is low in the blood donors of the Hangzhou area, and the positive rate of blood donors is associated with age, educational level, and times of blood donation. Increasing the number of repeat blood donations is helpful to improve blood safety.

Low SARS-CoV-2 Antibodies in Blood Donors After the First 6 Months of COVID-19 Epidemic in the Tobruk Region, Eastern Libya.

Coronavirus disease 2019 (COVID-19) is primarily a respiratory virus and there is no evidence of transfusion transmission for COVID-19;1, 2 however, estimation of the seroprevalence rate of antibodies to severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) in blood donors' population reflects the progression of the epidemic in the region. It is unclear how many people have contracted the virus since only symptomatic cases have been registered. For this reason, and as a part of the National Centre for Disease Control preparedness plan to combat the spread of the COVID-19 infection in the Tobruk region, eastern Libya, we conducted a cross-sectional study between January 15 to February 15, 2021, six months after the identification of the first confirmed COVID-19 case in the region on 23 July 2020. 3.

Pretransplantation seroreactivity in kidney donors and recipients as a predictive factor for posttransplant BKPyV-DNAemia.

BK polyomavirus (BKPyV) often reactivates after kidney transplantation, causing BKPyV-associated nephropathy (BKPyVAN) in 1%–10% of cases with a potential detrimental effect on allograft survival. Kidney transplant recipients are regularly screened for BKPyV DNA in plasma. As this strategy may not always reduce the risk of BKPyVAN, other predictive markers are needed. To evaluate the role of pretransplant BKPyV-specific antibody, 210 kidney transplant recipients and 130 donors were screened for BKPyV DNA and BKPyV-specific antibodies. We found that the donor BKPyV immunoglobulin G (IgG) seroprevalence and antibody level were strongly associated with BKPyV-DNAemia and BKPyVAN, although multivariant analysis found the presence of anti-BKPyV-specific antibodies as a predictive factor only for BKPyV-DNAemia. The pretransplant recipient status had no effect on posttransplant BKPyV-DNAemia and BKVAN. BKPyV IgG levels remained stable in BKPyV-negative recipients during 1-year follow-up, while a considerable increase was observed in BKPyV-positive patients. The presence of anti-BKPyV-specific antibodies in kidney allograft donors is a good and reliable predictive marker for posttransplant BKPyV replication with relevance to risk stratification in transplant recipients.

Analysis of 52 240 source plasma donors of convalescent COVID-19 plasma: Sex, ethnicity, and age association with initial antibody levels and rate of dissipation.

BackgroundCOVID‐19 convalescent plasma (CCP) was approved under emergency authorization to treat critically ill patients with COVID‐19 in the United States in 2020. We explored the demographics of donors contributing plasma for a hyperimmune, plasma‐derived therapy to evaluate factors that may be associated with anti‐SARS‐CoV‐2 antibody response variability and, subsequently, antibody titers.Study DesignAn electronic search of CCP donors was performed across 282 US plasma donation centers. Donations were screened for nucleocapsid protein‐binding‐IgG using the Abbott SARS‐CoV‐2 IgG assay.ResultsOverall, 52 240 donors donated 418 046 units of CCP. Donors were of various ethnicities: 43% Caucasian, 34% Hispanic, 17% African American, 2% Native American, 1% Asian, and 3% other. Females had higher initial mean anti‐SARS‐CoV‐2 antibody titers but an overall faster rate of decline (P < .0001). Initial antibody titers increased with age: individuals aged 55 to 66 years had elevated anti‐SARS‐CoV‐2 titers for longer periods compared with other ages (P = .0004). African American donors had the lowest initial antibody titers but a slower rate of decline (P < .0001), while Caucasian (P = .0088) and Hispanic (P = .0193) groups had the fastest rates of decline. Most donor antibody levels decreased below the inclusion criteria (≥1.50) within 30 to 100 days of first donation, but donation frequency did not appear to be associated with rate of decline.ConclusionSeveral factors may be associated with anti‐SARS‐CoV‐2 antibody response including donor age and sex. Evaluating these factors during development of future hyperimmune globulin products may help generation of therapies with optimal efficacy.

Sero-Prevalence of COVID-19 in Blood Donors of North India – Single-Center Report

Background and Objectives: COVID-19 has infected and caused the deaths of millions of people globally with India being the second most affected country in the world. The primary objective of the study was to determine the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) antibodies in healthy blood donors in North India. The secondary objective of the study was to find the association of vaccination and infection with seropositivity in the blood donors. Methods: All blood donor samples were screened for the presence of IgG antibodies against SARS CoV2 spike (S1) protein. Anti-SARS CoV2 IgG antibody status, demographic data, history of past COVID infection, and vaccination of all eligible donors in the study period were collected. Seroprevalence was calculated as the percentage of total number of donors positive for anti-SARS CoV2 IgG antibodies. Month-wise seroprevalence was also calculated and analyzed. Results: Out of 1456 donors, 874 were found to be seropositive, resulting in a seroprevalence of 60%. Seroprevalence was found to be 38.3% and 77%, respectively, in the months of April and May 21. Seropositivity was 100%, 92%, 79%, and 54% in those with a history of both COVID infection and vaccination, vaccination only, infection only, and no history of vaccination or infection, respectively. Conclusion: Blood donors represent an easy access to seroprevalence studies and need to be tapped at the national level to obtain a temporal picture of the COVID-19 situation to guide healthcare policies, mark regions where vaccination drives need to be intensified.

Prevalence of Irregular Red Cell Antibodies in Healthy Blood Donors at a Stand-Alone Blood Centre in Gujarat

Background: Blood transfusion therapy involves multiple steps to ensure selection of safe blood component for transfusion. This includes testing for infectious markers, full ABO compatibility, free from any irregular red cell antibodies especially which are reacting at wide thermal amplitude and acceptable donor's red cell survival rates without destruction of recipient's red cells. Objective: This study was aimed to assess prevalence and type of irregular red cell antibodies in a large number of blood donor population at a standalone blood centre in Gujarat. Methods: This retrospective observational study included blood donor samples for antibody screening from January 2018 to March 2022. A total of 2,16,576 healthy blood donors including 2,00,493 (92.57%) males and 16,083 (7.43%) females were screened. Results: The prevalence of irregular red cell antibodies was 0.03 per cent in our donor population. Of the total 66 donors with red cell antibodies, 53(80.30%) had alloantibodies, 8(12.12%) had autoantibodies and 6 donors (9.09%) showed positive antibody screening with inconclusive results. We also found one case of cold antibody. Conclusion: Alloimmunization to red cell antigens is a challenging task for current transfusion practices. The antibody screening in blood donors may improve the quality and safety of blood transfusion in the recipients. It also reduces the risk of complications from incompatible blood transfusions. Keywords: antibody screening, allo-antibody identification, autoantibody, safe blood transfusion, hemolytic transfusion reaction.

Infectious disease model generalization based on diffuse perturbations under conditions of body's temperature reaction

The infectious disease mathematical model is generalized based on the influence of diffuse perturbations on the development of the disease under conditions of the body's temperature reaction. The singularly perturbed model problem was reduced with delay to a sequence of problems without delay, for which the corresponding asymptotic expansions of solutions are obtained. The presented results of computer modeling in various situational states illustrate the expected decrease in the growth rate of the number of viral particles as a result of the action of the body's protective temperature reaction. The results of numerical experiments demonstrate the influence of the diffuse effect of “scattering” of forcing factors on the dynamics of a viral disease under conditions of the body's temperature reaction are presented too. It is noted that the decrease of the model amount of antigens in the epicenter of infection to a non-critical level caused by diffuse “scattering” over a relatively short time period makes them further destroyed by immune agents presented in the body, or requires the introduction of an injection solution with a smaller amount of donor antibodies.

Seroepidemiology of Toxoplasma gondii Infection in Blood Donors from Western Romania.

Background: Toxoplasma gondii is estimated to infect 33% of blood donors worldwide, and seroprevalence varies widely between countries. We aimed to evaluate, for the first time, the seroprevalence and risk factors associated with T. gondii in blood donors from Western Romania. Methods: Serologic testing to demonstrate the presence of T. gondii antibodies was conducted in 1347 healthy blood donors. Risk factors for T. gondii infection were assessed through an epidemiological questionnaire. Results: The overall prevalence of T. gondii antibodies was 45.9%, with a significant age-associated increase (p < 0.001) from 32.6% in age group 18–25 years to 67.6% in age group 56–63 years. T. gondii seroprevalence decreased with increasing level of education, from 64.3% in individuals who graduated from elementary/middle school to 40.4% in those who graduated from University (p < 0.001). The multiple logistic regression analysis revealed that age, level of education and having pets (cats and/or dogs) were significantly associated with T. gondii infection. Conclusions: This study brings new and valuable data regarding the seroepidemiology of T. gondii infection in Romania. Our findings indicate a high prevalence of T. gondii antibodies in blood donors and may serve as a starting point for further epidemiological studies that should lead to implementation of prevention programs for toxoplasmosis.

Diagnostics of the Epstein-Barr Virus Before and After Lung Transplantation in a Patient With Developing Posttransplant Lymphoproliferative Disease: A Case Report

The most important risk factor for the development of posttransplant lymphoproliferative disorders (PTLD) is Epstein-Barr virus (EBV) infection after transplant. It increases in seronegative EBV recipients from 23% to 50%. The aim of the study was to assess the serologic status of EBV infections (before lung transplant) and the expression of the virus itself after lung transplant in a 25-year-old patient with cystic fibrosis. In a 25-year-old patient with cystic fibrosis, immediately before lung transplant, all diagnostically significant antibodies related to EBV infection were determined in blood serum using enzyme-linked immunosorbent assay methods, using tests by Euroimmun and PerkinElmer Company. Additionally, the organ donor's serologic profile was assessed with the same tests. After lung transplant, the risk of EBV infection was monitored in whole blood and virus expression was determined by reverse transcriptase–polymerase chain reaction with Biomerieux Argene tests. Before lung transplant, the patient was shown to have no antibodies against EBV in both IgM and IgG classes. The constellation of organ donor antibodies clearly indicated a past infection. The presence of EBV virus copies in whole blood was demonstrated in the patient 9 months after transplant. Constant monitoring of the patient and modification of the treatment did not, unfortunately, protect him from the development of PTLD. The obtained results clearly confirm the purposefulness of both serologic and molecular determinations in lung recipients related to EBV. The likelihood of developing PTLD increases both in people who have not had EBV infection and patients with reactivation of the infection.

Seroprevelance of cytomegalovirus in healthy blood donors in Kafr El Sheikh General Hospital

Background and aim Cytomegalovirus (CMV) transmission to seronegative patients with inadequate immunity might result in significant consequences. The goal of the study was to determine the prevalence of CMV antibodies in healthy blood donors at the Kafr El Sheikh General Hospital. Patients and methods This research enrolled 100patients with the same inclusion and exclusion criteria, in age ranging between 18 and 60 years, with confirmed seronegativity for hepatitis C virus, hepatitis B virus, and HIV. All patients were asked to complete history taking, full clinical examination, laboratory assessment, and peripheral blood samples. The blood samples were taken from each individual to test for CMV immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies. Another sample was taken from IgM-positive cases in order to do PCR testing for CMV DNA. Results All cases among the study group were showing a positive CMV IgG with a high rate up to (100%). Consequently, in the general hospital in Kafr El Sheikh, healthy blood donors had a significant prevalence of CMV IgG. While, there were three (3%) patients of them had positive CMV IgM and 97 (97%) patients of them had Negative CMV IgM, this indicates a rarity of CMV IgM in healthy blood donors at Kafr El Sheikh General Hospital. Conclusion The high seroprevelance of CMV is a barrier to developing blood products of seronegative CMV in blood banks; nonetheless, we found that concentrated screening of a specific group of blood donors would be the best way to achieve this goal.

A Positive CDC T-cell Crossmatch is Strongly Associated with Allograft Loss and Early Rejection in Pediatric Heart Transplant Recipients

<h3>Purpose</h3> A recent multi-center study (CTOT-04) reported similar first year outcomes in children with CDC T-cell crossmatch (XM) + and XM- heart transplant (HT) but was underpowered and had only 11 children in the CDC+ HT group. We assessed the association of donor specific T-cell CDC and Flow XM HT with the risk of rejection and allograft loss in US pediatric recipients over 20 years. <h3>Methods</h3> We queried the OPTN database for all pediatric HT performed between 1999 and 2019. Donor specific T-cell XM results were categorized as CDC+, Flow+/CDC Unknown, Flow+/CDC-, and Flow-. Covariate adjustment using a propensity score balanced risk factors between the XM+ and XM- groups. <h3>Results</h3> Of 4695 pediatric HT, there were 165 CDC+, 288 Flow+/CDC Unknown, 94 Flow+/CDC-, and 4148 Flow- recipients. The median age at HT was 7 years, 44% female, 55% white, and 44% had a pre-HT diagnosis of CHD. Pre-HT diagnosis, hemodynamic support, and year of heart transplant differed between the XM+ and XM- groups prior to propensity score adjustment. After adjusting for propensity score, children with a CDC+ HT were significantly more likely to lose their allograft or develop rejection requiring treatment in the first post-HT year (<b>Table</b>). Propensity score matching and stratification by propensity score quintile demonstrated similar results. Over the period of the study, there was a significant shift in the type of XM assays performed (1999: 90% of HT with CDC XM, 32% Flow XM; 2019: 28% of HT with CDC XM, 87% Flow XM). <h3>Conclusion</h3> Children receiving a CDC+ XM HT are at higher risk of graft loss and rejection during the first post-transplant year, suggesting higher anti-HLA antibody burden in such recipients. The lack of differences in allograft loss and rejection with a positive Flow XM alone may be due to current treatment strategies. The shift away from performing a CDC XM results in a loss of important prognostic information. Prospective clinical trials of donor acceptance and antibody treatment strategies are needed.

HIGH TITRE ANTI-A AND ANTI-B ANTIBODIES IN GROUP ‘O’ BLOOD DONORS - A TERTIARY CARE HOSPITAL BLOOD BANK EXPERIENCE

Objective: To determine the frequency of titre anti-A and anti-B antibodies in donors with blood group O. Material and Methods: The study was conducted at Combined Military Hospital Multan from October 2019 to April 2020. This cross-sectional study has conducted after the approval of ethics review committee; A total of 300 individuals with blood group O reported for blood donation during the study period were considered in this study. After their consent, 10 ml whole blood of each donor was collected in two tubes, 3 ml collected in Ethylenediaminetetraacetic acid (EDTA) tube and 7 ml in plain tube. Anti-A &amp; anti-B antibodies titers were performed using pooled blood group A and B red cells by tube method at room temperature and 37° C. Results: Male consisted of 174 (58%) and female consisted of 126 (42%) with male to female ratio of 1.5:1 out of 300 blood donors. The ages of individuals range from 20 to 50 years (32.8 ± 7.2). The frequencies of titer of anti-A antibodies and anti-B antibodies were found to be 17.7% and 9.0% respectively. Conclusion: Titer of anti-A antibodies is high in considerable number of blood group O donors supports cautious use of Blood group O products in non-O recipients without screening. However, frequency of titer of anti-B antibodies was found to be relatively low. Key Words: Anti-B, Anti-A, High titre, Blood group O, Non-O Blood group.