Transfusion Safety Research Articles

Silent St. Louis encephalitis virus circulation evidence by a haemovigilance survey in a centralized blood bank.

Saint Louis encephalitis virus (SLEV) re-emergence and its geographical expansion, evidenced by its emergence in previously unaffected areas, have raised significant public health concerns. We aimed to show the usefulness of haemovigilance as an effective tool to fill arboviruses surveillance gaps to track trends and identify hotspots. Within the framework of a blood bank haemovigilance program, we performed a survey to evaluate the potential threat of circulating mosquito-borne infections for transfusion safety. SLEV was detected by a PCR targeting the conserved NS5-gene region, and the PCR-product was subjected to direct nucleotide sequencing reaction. The SLEV-strain detected in the blood donor (OR236721) clustered with previously reported CbaAr-4005, 79V-2533, and MN413675 isolated in Córdoba (2005, epidemic), Santa Fe (1979, non-epidemic) and Buenos Aires (2013, non-epidemic), with 97% identity. Herein, we show the usefulness of haemovigilance in uncovering the silent circulation of arboviral infections. Implementing this systematic surveillance approach would allow for monitoring the distribution and incidence of vector-borne diseases, providing information that could prevent the spread of the virus and its introduction into novel biomes. Ultimately, leveraging haemovigilance enables timely identification of potential outbreaks and empowers policymakers to make well-informed decisions to safeguard public health.

Evaluating bacterial contamination detection methods in blood units returned over 30 minutes: Implications for transfusion safety in resource-limited settings

Evaluating bacterial contamination detection methods in blood units returned over 30 minutes: Implications for transfusion safety in resource-limited settings

Red Blood Cell Transfusion Practices.

Opportunities to improve transfusion safety occur at lower hemoglobin (Hgb) thresholds and single-unit transfusions. Efforts to improve compliance with transfusion guidelines and single-unit transfusion practices reduce transfusions and lead to improved outcomes. To evaluate demographic and practice characteristics associated with lower Hgb thresholds and single red blood cell (RBC) unit transfusion practices. This study used the College of American Pathologists (CAP) Q-Probes format with the recent 2020 and 2017 surveys of participating institutions. High rates of transfusion review and compliance were observed with institutions reporting RBC transfusions meeting institutional guidelines. CAP inspection participants and those with a formal policy to encourage single-unit transfusions showed a trend toward greater compliance. Comparison of 2020 and 2017 survey results showed favorable downward trends in the Hgb threshold for transfusion compliance review and pretransfusion and posttransfusion Hgb values. Institutions reporting initiatives to decrease transfusions, teaching hospitals, and those with updated guidelines in alignment with recent literature reported lower pretransfusion Hgb levels in both studies. The 2020 study showed greater single-unit transfusion use among hospitals with patient blood management programs, larger institutions, and those training pathology residents. Single-unit transfusion rates varied by hospital service, with highest rates reported within hematology/oncology (99 of 138 [71.7%]), intensive care (147 of 215 [68.4%]), and medicine (419 of 666 [62.9%]) services. Transfusion practice improvement programs to decrease RBC transfusions include the use of single-unit transfusions and lower institutional pretransfusion Hgb thresholds. Opportunities to lower transfusion thresholds and increase single-unit transfusions exist in surgical and obstetrics services.

Application of exchange transfusion in neonates with severe pertussis and hyperleukocytosis

To investigate the efficacy and safety of exchange transfusion in neonates with severe pertussis. A retrospective analysis was performed for the medical data of five neonates with severe pertussis who underwent exchange transfusion in the Department of Neonatology, Hunan Children's Hospital, from August 2019 to March 2024. The clinical characteristics of the patients were summarized, and the efficacy and adverse reactions of exchange transfusion were analyzed. All five neonates had the symptoms of hypoxemia, recurrent apnea, and heart failure and required invasive mechanical ventilation. Two cases of pulmonary hypertension were observed, one of which was complicated by decompensated shock. Before exchange transfusion, the five children had a median leukocyte count of 82.60×109/L, a median absolute lymphocyte count of 28.20×109/L, and a median absolute neutrophil count of 43.10×109/L, and reexamination at 4 hours after exchange transfusion showed that these values decreased to 28.40×109/L, 7.60×109/L, and 15.40×109/L, respectively. The four children who underwent exchange transfusion in the early stage of cardiopulmonary failure showed varying degrees of improvement in oxygenation and a reduction in the partial pressure of carbon dioxide, and they were discharged after improvement; the one child who underwent exchange transfusion in the late stage of cardiopulmonary failure ultimately died. No child experienced severe adverse reactions related to exchange transfusion. For neonates with severe pertussis, initiating exchange transfusion in the early stages of cardiopulmonary failure can effectively reduce leukocyte levels, potentially improve survival rates, and is relatively safe.

The infected blood inquiry: Impact on public perceptions of blood supply risk, safety, and donation attitudes.

The UK's Infected Blood Inquiry (IBI) highlighted a major public health scandal, with at least 30 000 people infected and more than 3000 deaths attributable to infected blood and blood products. This study investigates the impact of the IBI announcement on May 20, 2024, on public perceptions of blood supply risk, safety, and donation intentions in the UK compared to the USA. A 2 (country: UK vs. USA) × 2 (time: pre-, post-IBI announcement) between-within-subject study was conducted with 1635 participants (888 UK, 747 USA). Pre-IBI data were collected from May 3 to 7, 2024, and post-IBI data from May 30 to June 30, 2024. Key measures were perceived infection risk from transfusion, transfusion safety, willingness to donate and encourage others. The impact was assessed using differences-in-differences (DiD) and reliable-change-indices (RCI). UK participants showed a significant but small decrease in perceived safety compared to USA participants, with 1 in 30 UK individuals perceiving a significant reduction in perceived transfusion safety. Decreases in perceived safety were associated with significant decreases in willingness to donate and encouragement of others in the whole sample and in USA participants and significant decreases in willingness to encourage others in UK participants. Older people reported a greater reduction in safety, and non-donors were more likely to be put off donating and not ask others to donate as a result of their perception that safety had been reduced. Overall, perceived safety decreased marginally in the UK general population. Future research should explore the long-term impacts of the IBI.

A prospective study to evaluate the clinical specificity of the cobas® MPX test kit for screening for HIV RNA, HCV RNA, and HBV DNA in blood donation samples using the cobas® 6800 system in HBV endemic areas

BackgroundNucleic acid testing (NAT) is widely used for screening blood donors for infectious diseases to enhance transfusion safety. Roche's advanced cobas® MPX assay detects human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) using the cobas® 6800/5800 Systems, based on real-time PCR technology, providing improved sensitivity. This study aims to evaluate the clinical sensitivity and specificity of the cobas® MPX assay and its effectiveness in identifying infected donors in HBV endemic areas, particularly those with occult HBV infection (OBI). Materials and methodsA total of 12,067 donor samples from the Dalian Blood Center (DLBC, northern China) were tested for HIV, HCV, and HBV using both the cobas® MPX assay on the cobas® 6800 system and the previous generation cobas® TaqScreen MPX test v2.0 on the cobas s 201 system as the reference method. Testing was conducted using individual-donation testing (IDT) and primary pool of six donations (PP6), following the manufacturer's instructions and the operational procedures of the instruments. Samples with inconsistent results underwent repeated confirmation tests. ResultsCobas® MPX demonstrated 100.00 % overall percent agreement (95 % CI, 99.22 %-100.00 %) for IDT and 99.89 % (95 % CI, 99.82 %-99.95 %) for PP6. Kappa coefficients were 1.0 for IDT and 0.76 for PP6. Cobas® MPX specificity was 100.00 % (95 % CI, 99.22 %-100.00 %) for IDT and 99.99 % (95 % CI, 99.94 %-100.00 %) for PP6. Sensitivity was 100.00 % (95 % CI, 2.50 %-100.00 %) for IDT and 86.67 % (95 % CI, 68.36 %-95.64 %) for PP6. A total of 12 HBV NAT-yield cases were detected by cobas® MPX. ConclusionCobas® MPX demonstrated outstanding sensitivity and specificity in screening HIV, HCV, and HBV in routine blood donations, particularly enhancing occult HBV detection in endemic regions.

Using Soluble CD38 to Overcome Daratumumab Interference in Pretransfusion Compatibility Testing

Background: CD38 is a protein highly expressed on myeloma (MM) cells that has been shown to be an effective target antigen for monoclonal antibody therapies, so treatment with anti-CD38 monoclonal antibodies is a first line therapy for patients with MM. Although CD38 is weaker expressed on erythocytes anti-CD38 binds to CD38 on reagent RBCs and cause panreactivity in vitro and subsequent false positive reactions in indirect antiglobulin tests (IAT), antibody detection (screening) tests, antibody identification panels, and anti-human globulin (AHG) crossmatches. These findings suggest that the soluble CD38 method could improve transfusion safety for patients receiving anti-CD38 therapy, particularly in urgent clinical settings This study aims to evaluate the effectiveness of a new soluble CD38-based method in mitigating Daratumumab interference during pretransfusion compatibility testing." Methods: We evaluated the Grifols sCD38 method in 20 patients and compared it with the DTT method Results: In our experience the sCD38 method reduced testing time from 150 to 50 minutes and demonstrated 100% efficacy, compared to 90% with DTT. The sCD38 effectively mitigated the interference caused by anti-CD38 antibodies in 10 (100% efficacy) of patient samples tested while DTT was successful in only 9/10 (90% efficacy); no interference was observed in patients presenting anti erythrocyte antibodies. Moreover, there was no negative influence on DTT sensitive blood group systems such as KEL upon sCD38 treatment. Conclusions: In our Laboratory, in the year 2023, we processed 129 patients treated with anti-CD38. Therefore the reduction from 150 to 50 minutes in the time needed to perform tests for mitigation of anti-CD38 interference appears to be relevant with a recovery of approximately 210 technical-hours per year. Another highly appreciated operational aspect was the possibility of treating the patient's plasma and perform tests using automatic instruments (Erytra Grifols) available in our laboratory. In the evaluation of this new method, we did not observe failures in the mitigation of anti-CD38 interference. Furthermore, the results obtained in the samples that presented allo or auto antibodies were not affected by the treatment with sCD38. In our experience Grifols sCD38 assay is straightforward and quick to perform ant it is superior to DTT treatment in the mitigation of anti-CD38 antibody interference in MM patients treated with Daratumumab.

Electronic prescription of Labile Blood Products: a cultural revolution by the APHM and EFS PACA-Corsica!

The electronic prescription of Labile Blood Products was recommended in a 1997 directive, to ensure transfusion safety in healthcare services. Following multiple institutional reminders by the Haemovigilance Unit of the Marseille Public Hospitals (APHM), the board of directors decided to set up a project for electronic transfusion records. Here we present the issues arising from this computerisation and the impact of this change of practice on the APHM and the Etablissement Français du Sang PACA-Corse (EFS PACA-Corsica; French Blood Institute Provence-Alpes-Côte d’Azur-Corsica).Concerning the APHM, we were overly optimistic when designing the prescription of Labile Blood Products (LBP), thinking that prescribers would choose the correct product qualifications. Unfortunately, the choice of LBP qualifications was excessive, resulting in product reception being blocked for the medical units. Furthermore, we were also faced with a resistance to change from the older doctors, while the younger doctors and junior doctors at ease with computers rapidly adhered to the tool.Concerning the EFS PACA-Corsica, this change in practice disconnected the link between the software in charge of red cell immunohaematology and LBP delivery, requiring the development of a new tool to re-establish a link. The EFS demanded a remote print-out, as a back-up for the electronic delivery of the prescription. The issue around identity discordance reinforced the ties between the APHM Haemovigilance and Identity Vigilance Units and the EFS.The partnership between our two structures was beneficial for the implementation of electronic transfusion records. The APHM gained in safety, obliging prescribers to note the duration of transfusion, and in healthcare traceability (reception, transfusion, adverse event reporting etc.). For the EFS PACA-Corsica, despite the difficulties encountered with software when the tool was first implemented, electronic nominative prescription made tasks simpler, gave better access to transfusion data, and reduced the number of phone calls from medical units inquiring about patient immunohaematology results.The comprehension and attentiveness between our two entities enabled us to complete this project and to resolve the problems as they appeared.

The safety of pathogen-reduced platelet transfusions in critically ill term and preterm neonates.

Platelet transfusions carry an important risk of infection transmission. The Mirasol Pathogen Reduction Technology system for platelets uses riboflavin and UV light to introduce irreparable lesions into nucleic acids, thereby inhibiting pathogen replication and inactivating white blood cells. The objective of this study is to evaluate the safety of pathogen-reduced platelet transfusions (PRPTs) in critically ill infants in a neonatal intensive care unit (NICU) in the Caribbean. We conducted a descriptive retrospective study of the use of Mirasol PRPTs in patients admitted to the NICU of the general hospital in Curaçao from February 2016 to April 2023. A total of 208 PRPTs were administered to 46 patients (median [range] transfusions per patient: 3 [1-24]). Three patients were born term, and 43 were born preterm (median [range] gestational age: 27 4/7 weeks [24 6/7-36 6/7]). PRPTs were well-tolerated and no complications occurred, especially no signs of haemolysis nor any signs of new infection within 24 h after transfusion. Twenty-one of 46 patients (46%) died during their admittance. None of the deaths were deemed related to PRPT. Mirasol PRPT appears to be safe for use in critically ill neonates, including extremely preterm neonates.

Frequencies and causes of ABO-incompatible red cell transfusions in France, Germany and the United Kingdom.

Prevention of ABO-incompatible red cell transfusions (ABO-it) requires accurate donor and patient identification and correct application of processes for transfusion safety. In France and Germany, a bedside identity check and ABO compatibility test are performed. In the UK, an identity check, often structured as a bedside checklist, is performed with or without electronic patient identification (ePID). To compare the efficacy of ABO-it bedside preventive measures, frequencies and causes of ABO-it between 2013 and 2022 were investigated in all three countries. Despite differing bedside safety measures, similar average ABO-it frequencies were observed in France (0.19 [SD:0.09]/100 000 issued red cell units) and in the UK (0.28 [SD:0.17]/100 000), whereas a higher frequency (0.71 [SD:0.23]/100 000) was observed in Germany which has similar bedside safety measures to France. ABO-it resulted mostly from erroneous patient identification and transfusion of a red cell unit intended for another patient. In France and Germany, all ABO-it were associated with incorrectly performed identity check and ABO compatibility test. In the UK, most ABO-it were associated with incorrectly performed identity checks. Current measures to prevent ABO-it are not fully effective. Further development and implementation of effective patient identification systems, including electronic information systems, across the entire transfusion process, should be considered.

Identification of two novel variants, c.-35A>T and c.[-35A>T, 725T>G], in the FUT1 gene in a patient exhibiting the para-Bombay phenotype.

Reduced or absent H antigens on red cells with the (para-)Bombay phenotype can arise from FUT1 gene mutations, impacting the structure and function of 1,2-L-fucosyltransferase 1 (1,2-L-FucT1). Here, we identified the novel mutations in one patient displaying the para-Bombay phenotype and examined the potential molecular mechanisms underlying this phenotype. ABH antigens and antibodies were detected in patient's blood and saliva using serological methods. The genotypes of ABO, FUT1, and FUT2 were imputed using the genetic variations discovered in the whole exome sequencing data. Three-dimensional (3D) models of FUT1 variants were built using Deepmind's AlphaFold2 and HDOCK, and the possible effects of the variants were predicted to evaluate using DynaMut2 and Polyphen-2. Serological analysis confirmed the para-Bombay B phenotype producing anti-HI and exhibiting normal genotypes ABO*B.01/O.01.02 and FUT2*01.09/01.09. Remarkably, the phenotype is caused by a compound heterozygous genotype: one allele containing the novel c.-35A>T mutation and the known c.725T>G mutation (p.Leu242Arg) of FUT1, and the other allele containing the c.-35A>T mutation. From the computerized stimulation analysis, p.Arg242 of the FUT1 variant may be detrimental, destabilizing, and probably damaging to 1,2-L-FucT1, although not altering the 3D structure of the entire enzyme. The c.-35A>T promoter DNA left at the binding interface of both ZID and c-Rel transcription factors may enable regulation of 1,2-L-FucT1 function at gene promoters. We identified the two novel variants, c.-35A>T and c.[-35A>T, 725T>G], in the FUT1 causing the para-Bombay phenotype. This finding may clarify the molecular mechanisms and enhance blood transfusion safety.

Whole blood and freeze-dried plasma in Canadian trauma care.

SummaryThis article highlights the crucial role of blood transfusion in trauma care and explores the historical and contemporary use of whole blood and freeze-dried plasma in Canadian health care. Early use of whole blood and freeze-dried plasma during global conflicts led to advancements in transfusion medicine. The transition to blood component therapy improved transfusion safety and precision. However, there is an increasing interest in using whole blood and freeze-dried plasma, supported by recent evidence suggesting potential benefits over blood component therapy, particularly in trauma cases. Canadian initiatives, such as leukoreduced whole blood production for the military, indicate efforts to address logistical challenges in delivering trauma care, especially in remote areas. Challenges remain, including logistical issues and regulatory complexities, requiring coordinated efforts for effective implementation. Overall, there's growing support for integrating whole blood and freeze-dried plasma into trauma care across Canada.

Safety of Hepatitis B Virus Screening in Blood Donors from the Hospital Foundation of Hematology and Hemotherapy of the State of Amazonas (HEMOAM) in the Brazilian Amazon

Background: Hepatitis B is an infectious disease of worldwide importance and of great interest to transfusion medicine. The Amazon region has areas of high endemicity, outlining a worrying scenario for transfusion and epidemiological safety. Objective: To analyze the profiles of serological and molecular markers for HBV of blood donors from HEMOAM. Methods: Blood donors with different patterns of reactivity in serological and molecular screening for HBV were tested for viral load by the qPCR method at the reference center for liver diseases in the state of Amazonas. Results: A total of 230,591 donors were tested, with 3104 (1.34%) found reactive for HBV and 2790 (89.9%) found reactive for isolated anti-HBc. Viral load was not detected in 100% of donors reactive only to HBsAg, while 100% of donors with positive anti-HBc and positive HBsAg or HBV NAT demonstrated a detectable viral load. We also detected one case of occult hepatitis B (0.03%) only with reactive HBV NAT and five donors (0.2%) with positive anti-HBc and HBV NAT. Conclusions: With this result, the great importance of the anti-HBc test for the unsuitability of blood donors was verified, as well as the fundamental introduction of the HBV NAT test in screening for hepatitis B in Brazilian blood banks, as this was the only way to detect the viral infection burden in asymptomatic donors who previously would not be treated, which contributed to the maintenance of the endemicity of hepatitis B in the Brazilian Amazon.

HEV in Blood Donors in Switzerland: The Route to Safe Blood Products.

The hepatitis E virus (HEV) is an emerging infectious disease with zoonotic potential, causing acute hepatitis in humans. Infections in healthy individuals are often acute, self-limiting and asymptomatic, thus leading to the underdiagnosis of HEV infections. Asymptomatic HEV infections pose a problem for blood transfusion safety by increasing the risk for transfusion-transmitted HEV infections. Here, we describe the journey from determining the HEV seroprevalence among blood donors to the implementation of routine HEV RNA testing of all blood products in Switzerland in 2018 and summarise the HEV cases detected since. In total, 290 HEV-positive blood donations were detected by mini-pool nucleic acid testing (NAT) in Switzerland in the period of October 2018-December 2023, equal to an incidence of 20.7 per 100,000 donations. Thanks to the implemented scheme, no transfusion-transmitted infections occurred in this period. Furthermore, blood donation monitoring has proven to be an effective means of detecting HEV outbreaks in the general population. HEV cases in Swiss blood donors are caused by two major genotypes, the Swiss-endemic subtypes 3h3 and 3c. Interestingly, 11 HEV cases (5%) were of genotype 3ra, a variant found in wild and farmed rabbits. Our results indicate that mini-pool NAT is an efficient method to reduce the risk of transfusion-transmitted HEV infections.

Bacterial Contamination of Donor Blood Units in a Ghanaian Blood Bank: A Critical Concern for Transfusion Safety

Abstract Introduction/Objective Background: Blood transfusions, while life-saving, pose a significant risk to patient safety, with transfusion-associated bacterial sepsis emerging as a persistent and potentially fatal threat. The prevalence and severity of bacterial contamination in donor blood units necessitate regular surveillance to ensure safe and effective transfusion therapy. Aim This study aimed to identify and assess the susceptibility of bacterial isolates in whole blood donor units at the blood bank of Cape Coast Teaching Hospital in the Central Region of Ghana. Methods/Case Report Method(s): One hundred and three (103) units of stored whole blood units, declared safe for transfusion (testing negative for HIV I&II, HBsAg, HCV, and syphilis), were inoculated into Brain Heart Infusion Broth and incubated for 24 hours. The inoculated broths were then cultured on MacConkey agar (MAC), Chocolate agar (CHOC), and Blood agar. Gram-negative and Gram-positive isolates were identified using standard biochemical tests. Antimicrobial susceptibility testing was performed using the disc diffusion method. Results (if a Case Study enter NA) Results: Of the 103 donor blood units tested, 33 (32.03%) were found to have bacterial isolates. Gram-positive organisms accounted for 67.14% of the isolates, including Coagulase negative Staphylococcus, Bacillus spp, and S. aureus. Gram-negative bacteria constituted 32.86% of the isolates, with Citrobacter freundii, Serratia marcescens, E. coli, and Providencia stuartii identified. Notably, 62.9% of the bacterial isolates were skin commensals, while 25.7% were of enteric origin and 11.4% were of nosocomial origin. Resistance to commonly used antibiotics varied among isolates, with Coagulase-negative Staphylococcus exhibiting resistance to amoxicillin (92.86%) and erythromycin (76.19%), while Citrobacter freundii showed resistance to levofloxacin (75.00%) and ofloxacin (75.00%). Conclusion Conclusion(s): The high incidence of bacterial contamination in donor blood units highlights the need for improved phlebotomy procedures and decontamination practices at blood banks in Ghana to reduce the risk of sepsis in transfusion recipients. Furthermore, this study provides valuable information regarding antibiotic resistance patterns in bacterial isolates, emphasizing the importance of antibiotic stewardship in Ghana. In conclusion, this study underscores the urgency of addressing bacterial contamination in donor blood units in Ghanaian blood banks to enhance transfusion safety.

Serological profile of voluntary blood donors in a blood bank of tertiary health care centre- An institution-based study

Background: The safe transfusion of blood facilities is an essential component of an efficient, excellent healthcare sector. Unsafe blood transfusions can be a cause of transfusion-transmitted infections and can be lethal. The present study was conducted to find out the seroprevalence of HBsAg, HCV, HIV, malarial parasites, and syphilis in voluntary blood donors in a tertiary care center. Materials and methods: This prospective study was conducted at the blood bank of the Shri Mahant Indiresh Hospital, Dehradun. 16413 samples from all blood donations were screened for HBsAg, HCV, HIV 1 and 2, malaria, and syphilis. Samples were collected in vacutainers at the time of blood donation and screened for HIV 1and2, HBsAg, and HCV using the fourth-generation enzyme-linked immunosorbent assay technique. Syphilis was tested by Treponema antibodies using the VITROS Syphilis TPA Reagent Pack. Malaria was tested by pan malaria card, monoclonal anti-pan specific parasite lactate dehydrogenase antibody conjugated to colloidal gold, and another monoclonal anti-pan specific parasite lactate dehydrogenase antibody immobilized on a nitrocellulose strip in a thin line. Results: Out of 16413 blood donors 342(2.1%) were found to be seropositive and 16071 (97.9%) were found to be seronegative. The total number of donors, who were found positive for HBsAg/Anti HCV was 1 (0.3%). Out of the seropositive cases, HBsAg, HCV, HIV, and Syphilis infections constituted 28.9%, 27.5, 14.6, and 28.7% cases respectively. Conclusions: There is a need for the development and implementation of stringent donor selection and sensitive screening tests to reduce the risk of acquiring transfusion-transmitted illnesses.

Prevalence, incidence, and residual risk for human immunodeficiency virus among blood donors from 2003 to 2022 in Guangzhou, China.

China's significant population affected by HIV poses a substantial threat to blood transfusion safety. Despite advancements in blood testing techniques, a residual risk of HIV transmission persists. Accurately assessing HIV epidemic and the residual risk is vital for monitoring blood supply safety and evaluating the effectiveness of new screening tests. We conducted a retrospective analysis of HIV detection results among voluntary blood donors from 2003 to 2022. The study included data on HIV-confirmed positive donors, HIV prevalence, infection risk factors, and an incidence-window period mathematical model to estimate the residual risk of HIV. Between 2003 and 2022, HIV prevalence among blood donors in Guangzhou showed a peak-shaped trend, initially increasing before declining. The overall HIV prevalence was 18.9 infections per 100,000 donations. Male donors had a significantly higher prevalence compared with female donors. Donors aged 26-35 years had the highest prevalence. Ethnic minority donors had a higher prevalence compared with Han donors. Repeat donors had a lower prevalence compared with first-time donors. Donors from other provinces had a higher prevalence compared with local donors. During the period of 2003 to 2022, the residual risk of HIV in Guangzhou steadily decreased, reaching a notable 1 in 526,316 donations in the past two years. The HIV epidemic among blood donors in Guangzhou remains severe, but the residual risk of HIV is decreasing. Novel detection methods have proven advantageous in reducing this residual risk. Implementing additional effective measures is imperative to ensure blood safety and curb the spread of HIV.

Serological and molecular characterization of novel ABO variants including an interesting B(A) subgroup.

ABO grouping is the most important pretransfusion testing that is directly related to the safety of blood transfusion. A weak ABO subgroup is one of the important causes of an ABO grouping discrepancy. Here, we investigated the characterization of four novel ABO variants including a novel B(A) subgroup. RBCs were phenotyped by standard serology methods. The full coding regions of the ABO gene and the erythroid cell-specific regulatory elements in intron one were sequenced. The effect of the possible splice site variant was predicted by Alamut software. The 3D structural modeling of three relative B(A) enzymes (p.Met214Thr, p.Met214Val, and p.Met214Leu) were performed by PyMOL software. Four novel ABO alleles were identified with weak ABO expression in this study, in which two would lead to premature terminations, and two resulted in amino acid changes. In silico analysis revealed that the splice site variant c.155G>T had the potential to alter splice transcripts. 3D structural view shown that the variant amino acid position 214 was spatially adjacent to the donor recognition pocket residues (266Met and 268Ala) and just next to the 211DVD213 motif. The size of the side chain of Thr and Val is the smallest, Leu is medium, and Met is the largest, and the size changes in the critical position 214 may affect the donor recognition pocket. Four ABO subgroup alleles were newly linked to different kinds of ABO variants and the possible mechanism through which they produce weak ABO subgroups was analyzed in silico.

Evaluation of the analytical performance of four different manufacturer's reagent red blood cells in antibody detection and identification.

The detection/identification of clinically significant antibodies to red cell antigens form the foundation for safe transfusion practices. This study aimed to evaluate the diagnostic performance of commercially available 0.8% reagent red blood cells (RRBCs) in Australia. 166 patient-derived plasma samples with a positive indirect antiglobulin test (IAT) were tested using column agglutination technology (CAT) with Immulab, Bio-Rad, Grifols and QuidelOrtho screening and identification RRBCs with the respective manufacturer's proprietary CAT system. False-negative antibody screening and identification results were obtained with Bio-Rad (3/61), Grifols (14/68) and Quidel-Ortho (3/59) RRBCs when tested with the respective manufacturer's proprietary CAT system. Zero false-negative results were observed with Immulab RRBCs when tested with samples across all platforms. The sensitivity of the RRBCs used in this study were calculated to be 95.83% (95%CI 88.30-99.13%) for Bio-Rad RRBCs, 82.50% (95%CI 72.38-90.09%) for Grifols RRBCs and 95.65% (95%CI 87.82-99.09%) for QuidelOrtho RRBCs. The sensitivity of Immulab RRBCs were stratified based on performance in the 3 CAT platforms: Bio-Rad CAT (100%, 95%CI 95.01-100%), Grifols CAT (100%, 95%CI 95.49-100%) and QuidelOrtho CAT (100%, 95%CI 94.79-100%). RRBCs used in antibody detection and identification vary in diagnostic performance and should therefore be carefully considered before being implemented in routine patient testing.

Cold autoantibody interference in pretransfusion testing and its resolution: a case report

We report a case of cold autoantibody detected in a 69-year-old gentleman diagnosed with chronic lymphocytic leukemia and cold autoimmune hemolytic anaemia. Pretransfusion testing showed panagglutination in ABO grouping, antibody screening and identification, with positive direct antiglobulin test (DAT) and positive control cells. A cold autoantibody was suspected, however, the test using a prewarm method and washed RBC with warm saline failed to resolve it. Further tests using DTT-treated cells resolved the grouping as AB RhD positive and DAT as positive with anti-C3d only (control negative). Cold autoadsorption was done and repeated antibody screening using cold-autoadsorped plasma was negative, excluding the presence of alloantibody. The cold-agglutinin titer was >1028 having a wide thermal range. Crossmatching using cold autoadsorped plasma with the AB-positive donor blood was compatible and the patient was transfused safely. For such cold autoantibody cases, an extensive immunohematological workup is required to exclude underlying alloantibody for transfusion safety and efficacy. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1238-1242