Transfusion-transmitted infections

Prevalence of HIV, hepatitis B and hepatitis C infections among patients with thalassemia attending a tertiary care (rural) hospital

Introduction

The Sunderban area of West Bengal is home to tribal and religious minorities inhabiting various islands. There is a high prevalence of thalassemia among poverty-stricken residents of this region living with meagre health care facilities. This work was planned to determine the proportion of four viral transfusion-transmitted infections (TTIs): HIV-1, HIV-2, hepatitis B virus (HBV) and hepatitis C virus (HCV) among thalassemia patients attending the sole rural medical college in the region.

Materials and Methods

Thalassemia patients (n = 359, age ranging from 1 year to 60 years) attending the thalassemia clinic or being admitted to the indoor facilities for better management were included in the study. Only patients diagnosed with high-performance liquid chromatography (HPLC) and with classical clinical features were included in the study. Blood samples of these patients were tested for HIV as per NACO protocol. For HBV and HCV, samples were first tested serologically; reactive samples were collected and sent in the cold chain to a higher centre for nucleic acid amplification testing (NAAT) for qualitative and quantitative estimation. Clinical and laboratory data was collected, patients were followed up for complications and hospitalisation during the study period, and statistical analysis was performed.

Results

Majority of our patients had E-beta-thalassemia (245, 59.81%), followed by beta-thalassemia major (102, 28.30%). NAAT-confirmed HCV infection (14.21%) infection was the most common, followed by HBV (2.51%), and lastly by HIV-1 (0.58%) infection. Among infected thalassemia patients, the mean HCV RNA was 741063 ± 438514.67 IU/ml while the mean HBV DNA level was 4082863 ± 7298514 IU/ml. Co-infections of HIV-1 and HCV and that of HBV and HCV were noted in one patient each (0.28%). HCV-related liver disease (14.21%) and growth retardation (10.31%) were the most typical complication noted, and death occurred in five patients (1.39%) during the study period.

Conclusion

Primary care physicians should know HCV infection is the most common TTI among thalassemia patients in rural eastern India.

Associated criteria used in investigating suspected septic transfusion reactions: A scoping review

BACKGROUND AND OBJECTIVES

Septic transfusion reactions (STRs) occur as a result of bacterial contamination of blood or blood products, resulting in sepsis. This scoping review aimed to identify, explore and map the available literature on the STR criteria triggering the investigation of STR.

MATERIALS AND METHODS

Four electronic databases (MEDLINE, Web of Science, Science Direct, Embase) were searched to retrieve scientific literature reporting such criteria, published from 1 January 2000 to 5 May 2022. Grey literature was also searched from open web sources.

RESULTS

Of 1052 references identified, 43 (21 peer-reviewed and 22 grey literature) met the eligibility criteria for inclusion and data extraction after full article screening. Of them, most (27/43, 62.79%) were found to report a single set of criteria, and only two reported four or more sets of criteria. The analysis of 66 sets of criteria collected from the selected references revealed 57 different sets. A few sets of criteria used only one sign and symptom (s/s) (12.12%, n = 8), whereas 16 sets used 7-15 s/s (n = 16/66; 24.24%). Of the total 319 occurrences of s/s associated with the 66 sets of criteria, post-transfusion hyperthermia, body temperature increase and hypotension were the most common s/s categories. Of all the literature available, only one study tested the diagnostic accuracy of the STR criteria.

CONCLUSION

This scoping review revealed a substantial variation in criteria used to identify suspected STR. Consequently, conducting further studies to enhance the diagnostic accuracy of these criteria, which trigger STR investigations, is imperative for advancing clinical practice.

Epidemiology of HEV Infection in Blood Donors in Southern Switzerland

From 2014 to 2016, the number of hepatitis E virus (HEV) infections in southern Switzerland increased dramatically and suggested food as a potential infection reservoir. We evaluated the effects of food control measures introduced to limit HEV infections, assessing anti-HEV IgG and IgM rates in blood donors before and after the implementation of food control measures in 2017. From 2012 to 2013, we screened 1283, and from 2017 to 2019, we screened 1447 donors for IgG and IgM antibodies. No statistically significant differences were detected for IgG (32.8% from 2012 to 2013 vs. 31.1% from 2017 to 2019, p = 0.337) or IgM rates (2.0% from 2012 to 2013 vs. 2.8% from 2017 to 2019, p = 0.21). Rural provenience and age > 66 are predictors for positive IgG serology. A total of 5.9% of 303 donors included in both groups lost IgG positivity. We also determined nucleic acid testing (NAT) rates after the introduction of this test in 2018, comparing 49,345 donation results from southern Switzerland with those of 625,559 Swiss donor controls, and only 9 NAT-positive donors were found from 2018 to 2023. The high HEV seroprevalence in southern Switzerland may depend on different food supply chains in rural and urban areas. Local preventive measures probably have a limited impact on blood HEV risk; thus, continuous NAT testing is recommended.

Seroprevalence of leptospirosis among blood donors in an endemic area

Thailand is known to be endemic for leptospirosis. This bacterium may pose a potential risk to transfusion safety. This study was a cross-sectional study examining the seroprevalence of leptospirosis among Thai blood donors. A total of 1053 serum specimens collected from blood donors residing in 5 regions of Thailand during March to September 2020 were included in this study. All samples were tested for the presence of antibodies to 22 leptospiral serovars using the microscopic agglutination test (MAT) and anti-Leptospira IgG antibodies using commercially available enzyme immunoassay. We found no evidence of recent exposure to Leptospira spp. in sera of healthy Thai blood donors by MAT, including those in higher-risk areas. However, in this same group, we did find small numbers of past exposure (1.7%) to Leptospira spp. by IgG ELISA. According to the findings of this study, there is currently no evidence for implementing new blood banking procedures to identify possible carriers in Thailand, however these should be continually monitored and revised according to the infectious disease burden in each country. It should be noted that there was a difference in the occupation rate between the general population reported in Thailand and blood donors in this study; it may not reflect the actual situation in the country.

Prevalence of TTI among Indian blood donors

Transfusion Transmissible Infections (TTIs) such as human immune-deficiency virus (HIV-I/II), hepatitis B virus (HBV), Hepatitis C virus (HCV), Malaria parasite (MP) and syphilis can spread through contaminated blood or blood products. The present study was designed to analyze the prevalence of TTIs and their association with blood group, among the blood donors of Delhi. Blood group was determined by hem-agglutination using Gel card. HIV, HBV, and HCV test was performed by ELISA, syphilis by RPR and MP rapid card method. A total Transfusion Transmissible Infections (TTIs) such as human immune-deficiency virus (HIV-I/II), hepatitis B virus (HBV), Hepatitis C virus (HCV), Malaria parasite (MP) and syphilis can spread through contaminated blood or blood products. The present study was designed to analyze the prevalence of TTIs and their association with blood group, among the blood donors of Delhi. Blood group was determined by hem-agglutination using Gel card. HIV, HBV, and HCV test was performed by ELISA, syphilis by RPR and MP rapid card method. A total of 345(2.038%) blood donors were positive for TTIs. Prevalence of HBV, HCV, HIV-I/II, syphilis and MP were 188(1.111%), 73(0.431%), 34(0.201%), 49(0.29%) and 1(0.006%) respectively. Our result shows a trend of decrease in prevalence of TTIs; 2.267%, 2.111% and 1.614% between the year 2020, 2021 and 2022 respectively. Significant association of syphilis infection (P=0.036) and HCV infection (P=0.012) with ABO blood group antigen was observed. Blood group O donors were 1.81 times more infected with syphilis compared to donor having A and B antigen. Donors having blood group antigen B were 1.80 times more infected with HCV compared to donor not having B antigen. HBV and HIV prevalence found to be not associated with ABO and Rh blood group antigens. A low prevalence of TTIs positivity was observed among blood donors. Public awareness, proper counseling, medical examination and testing can help to minimize TTIs. Our study results shows ABO blood group has an association with HCV and VDRL infection.

Unbalanced T-cell subsets in pediatric patients with beta-thalassemia

BACKGROUND

Beta-thalassemia major is an autosomal recessive disorder in hemoglobin synthesis. Ineffective erythropoiesis is the main characteristic of the disease, which results in anemia following the extensive destruction of red blood cells. Chronic antigenic stimulation following frequent blood transfusions lead to immune abnormalities, especially regarding T cells, which is one of the reasons for the high susceptibility to infection in beta-thalassemia.

METHODS

Six pediatric patients and six age- and sex-matched healthy children were selected. Immunophenotyping of functional T-cells was performed using flow cytometry with staining for surface and intracellular markers. The proliferative response of T lymphocytes was also investigated after labeling with CFSE and following stimulation with anti-CD3 and anti-CD28.

RESULTS

Examination of T lymphocyte subpopulations showed a significant increase in regulatory T cells (Tregs) in beta-thalassemia patients. Hence, the Treg:Tcons (conventional T cells) and Treg:CD8 ratios were significantly increased. In addition, a significant increase in CD8 T cell proliferation activity was observed. Multivariate analysis showed a significant association of central memory cells with serum ferritin levels and the duration of transfusion. In particular, patients with cytomegalovirus (CMV) infection exhibited a significant increase in CD4 central memory cells.

CONCLUSION

Patients with beta-thalassemia have functionally distinct CD4 and CD8 T cell subsets imbalances, and this may contribute to their high susceptibility to infections and immune dysregulation.

Second hepatitis C virus transmission by blood components since introduction of mandatory NAT screening in Germany

BACKGROUND

Viral safety of blood products in Germany has improved significantly over the last two decades. We describe the second documented transfusion-transmitted (TT) episode for the hepatitis C virus (HCV) in Germany since mandatory nucleic acid amplification techniques (NAT) screening was introduced in 1999.

STUDY DESIGN AND METHODS

When a repeat donor who had tested negative for anti-HCV tested positive for HCV RNA by NAT in a minipool (MP) of eight, a look-back procedure was initiated. Qualitative, quantitative and genotyping assays were used to investigate the titers of the quarantined fresh frozen plasma (FFP) from the donor and a serum sample from the recipient of the pooled platelet concentrate (PPC). Amplified products of 5'UTR and HVR1 were used for sequence comparison to characterize the HCV genomic identity of donor and recipient samples.

RESULTS

All NAT tests utilized in this procedure were able to detect a low HCV RNA titer (~15 IU/ml) in the FFP from the donation. Dilution of FFP by factor 8 was performed to mimic an MP, and the detection rate correlated well with the claimed sensitivity of the tests. Analysis of donor and recipient samples revealed genotype 3a viral transmission confirmed by sequence analysis.

CONCLUSION

This TT HCV case could have been prevented by individual donation (ID) NAT. However, a low titer blood donation in the window period (WP) is very rare. Residual risk calculation for TT HCV in the WP revealed that, compared to MP-NAT testing, ID-NAT would improve blood safety only marginally.

[Molecular biology in a blood bank]

Medicine has had a vertiginous advance in the last two centuries. After the first successful transfusions, transfusional medicine and blood banks arose. The ladder perform vital functions, from donor screening to the studies for the analysis of blood that are carried out before its use for transfusion and the follow-up of patients who receive blood components. Molecular biology is highly relevant in these activities, since it has allowed the reduction of window periods for the detection of diseases transmissible by blood; it has allowed the complete study of the typing of blood groups and HLA molecules, and it has allowed the adequate phenotypic interpretation of patients and donors by being able to have their genotype. The most relevant impact of the implementation of molecular biology techniques was the screening for the detection of transfusion-transmissible diseases in blood donors, which has allowed improving the safety of the components obtained. Molecular biology techniques applied in the study of the donor-recipient have allowed better care of patients who have required a transfusion or transplant. In this work, it is reviewed the importance of molecular biology in blood banks, with which the care for the Instituto Mexicano del Seguro Social beneficiaries has improved, as well as for the blood donors who are mostly not insured.

Transmission of Hepatitis E Virus

Transmission of hepatitis E virus (HEV) occurs predominantly by the fecal-oral route. Large epidemics of hepatitis E in the developing countries of Asia and Africa are waterborne and spread through contaminated drinking water. The reservoir of HEV in developed countries is believed to be in animals with zoonotic transmission to humans, possibly through direct contact or the consumption of undercooked contaminated meat. And HEV transmission through blood transfusion, organ transplantation, and vertical transmission has been reported.

A Case of Fatal Clostridium perfringens Sepsis with Massive Hemolysis in the Setting of a Coincidental Platelet Transfusion

A 62-year-old woman with acute myeloid leukemia (AML) died of shock and massive hemolysis shortly after receiving two platelet transfusions at a routine clinic visit. Subsequent investigation into what was initially believed to be an acute hemolytic transfusion reaction secondary to platelet transfusions revealed that the patient died of Clostridium perfringens sepsis leading to massive hemolysis. Further investigation ruled out bacterially-contaminated platelets since a patient blood sample from 2 days prior had Clostridium species. The unusual findings and management considerations for this oncology patient are reviewed and compared with previously reported cases of C. perfringens transfusion-transmitted infections. Oncology patients may be especially susceptible to unusual presentations involving unusual pathogens.

Anti-Viral Photodynamic Inactivation of T4-like Bacteriophage as a Mammalian Virus Model in Blood

The laboratorial available methods applied in plasma disinfection can induce damage in other blood components. Antimicrobial photodynamic therapy (aPDT) represents a promising approach and is approved for plasma and platelet disinfection using non-porphyrinic photosensitizers (PSs), such as methylene blue (MB). In this study, the photodynamic action of three cationic porphyrins (Tri-Py(+)-Me, Tetra-Py(+)-Me and Tetra-S-Py(+)-Me) towards viruses was evaluated under white light irradiation at an irradiance of 25 and 150 mW·cm^−2, and the results were compared with the efficacy of the approved MB. None of the PSs caused hemolysis at the isotonic conditions, using a T4-like phage as a model of mammalian viruses. All porphyrins were more effective than MB in the photoinactivation of the T4-like phage in plasma. Moreover, the most efficient PS promoted a moderate inactivation rate of the T4-like phage in whole blood. Nevertheless, these porphyrins, such as MB, can be considered promising and safe PSs to photoinactivate viruses in blood plasma.

Cost Analysis of Platelet Transfusion in Italy for Patients with Chronic Liver Disease and Associated Thrombocytopenia Undergoing Elective Procedures

Purpose

Platelet transfusions (PT) are commonly used as prophylaxis in patients with chronic liver disease (CLD) and severe thrombocytopenia (TCP) before invasive procedures, in order to reduce risk of bleeding. The aim of this cost analysis was to generate a comprehensive estimate of costs of platelet transfusions in Italy, focusing on patients with severe TCP due to CLD undergoing an elective procedure.

Methods

The research was conducted in different phases: 1) assessment of a pre-specified framework for the identification of processes related to PT; 2) estimation of resource consumption through Delphi technique and collection of unit costs through literature; 3) development of a cost analysis to estimate the overall average costs per PT, focusing on a representative patient with CLD and severe TCP. Robustness of results was tested in a sensitivity analysis.

Results

Despite the lack of some cost components estimation and uncertainty related to event probability, the analysis showed a total cost of 5297 € for each PT in patients with CLD and severe TCP. The total cost was largely driven by direct costs (4863 €) associated with platelet collection, transfusion, and management of refractoriness, which accounted for 92% of total.

Conclusion

In an environment of limited resources, it is crucial for the healthcare service to have accurate and inclusive information on transfusion costs, incorporating not only the cost of blood products but also those related to collection and management. The analysis showed that platelet collection and administration costs add substantially to the cost of platelet products themselves. As expected, the highest cost was the transfusion process itself (44% of total), followed by refractoriness (43% of total). Since limited literature exists concerning these cost estimates, this analysis represents a step forward in understanding the economic burden of patients with CLD and severe TCP scheduled to undergo an invasive procedure.

Iron deficiency anaemia: pathophysiology, assessment, practical management

The WHO has recognised iron deficiency anaemia (IDA) as the most common nutritional deficiency in the world, with 30% of the population being affected with this condition. Although the most common causes of IDA are gastrointestinal bleeding and menstruation in women, decreased dietary iron and decreased iron absorption are also culpable causes. Patients with IDA should be treated with the aim of replenishing iron stores and returning the haemoglobin to a normal level. This has shown to improve quality of life, morbidity, prognosis in chronic disease and outcomes in pregnancy. Iron deficiency occurs in many chronic inflammatory conditions, including congestive cardiac failure, chronic kidney disease and inflammatory bowel disease. This article will provide an updated overview on diagnosis and management of IDA in patients with chronic conditions, preoperative and in pregnancy. We will discuss the benefits and limitations of oral versus intravenous iron replacement in each cohort, with an overview on cost analysis between the different iron formulations currently on the market.

Criminal and Civil Responsibility of the Donor in a Case of Transmission of Malaria by a Blood Transfusion in a Nonendemic Country

Introduction

The blood donation process is strictly regulated by law. The process includes the necessity of a medical history taken to determine if a donor is suitable to donate, which shall guarantee both donor and recipient safety. Supplementary screening for a limited number of infections is performed by antibody (HIV, HCV, syphilis) or antigen (HBV) tests or NAT (HIV, HCV, HBV).

Case Presentation

With regard to a possible infection due to (sexual) risk behavior or foreign travel, blood donation facilities are predominantly dependent on information provided by the donor. This is especially true for malaria in nonendemic areas such as Europe. Transmission of malaria by a blood transfusion in a nonendemic country that led to fulminant septic shock and death of the patient happened.

Discussion

From a legal perspective, the donor thus assumes a high level of responsibility with regard to the accuracy and completeness of the information provided on the donor questionnaire. Incorrect information may, as in this Austrian case reported, result in civil or criminal responsibility of the donor.

Blood Conservation and Hemostasis Management in Pediatric Cardiac Surgery

Pediatric cardiac surgery is associated with significant perioperative blood loss needing blood product transfusion. Transfusion carries serious risks and implications on clinical outcomes in this vulnerable population. The need for transfusion is higher in children and is attributed to several factors including immaturity of the hemostatic system, hemodilution from the CPB circuit, excessive activation of the hemostatic system, and preoperative anticoagulant drugs. Other patient characteristics such as smaller relative size of the patient, higher metabolic and oxygen requirements make successful blood transfusion management extremely challenging in this population and require meticulous planning and multidisciplinary teamwork. In this narrative review we aim to summarize risks and complications associated with blood transfusion in pediatric cardiac surgery and also to summarize perioperative coagulation management and blood conservation strategies.

Presence of viremia during febrile neutropenic episodes in patients undergoing chemotherapy for malignant neoplasms

The importance of viral infections as a leading cause of morbidity and mortality is well documented in severely immunosuppressed patients undergoing allogeneic stem cell transplantation. By contrast, viral infections generally receive less attention in patients with malignant disorders undergoing chemotherapy, where the onset of neutropenic fever is mostly associated with bacterial or fungal infections, and screening for viral infections is not routinely performed. To address the occurrence of invasive viral infections in a clinical setting commonly associated with less pronounced immunosuppression, we have prospectively screened 237 febrile neutropenic episodes in pediatric (n = 77) and adult (n = 69) patients undergoing intensive chemotherapy, primarily for treatment of acute leukemia. Serial peripheral blood specimens were tested by RQ-PCR assays for the presence and quantity of the clinically relevant viruses CMV, EBV, HHV6 and HAdV, commonly reactivated in highly immunocompromised patients. Viremia was documented in 36 (15%) episodes investigated, including the detection of HHV6 (n = 14), EBV (n = 15), CMV (n = 6), or HAdV (n = 1). While low or intermediate levels of viremia (<10⁴ virus copies/mL) were commonly associated with bacterial or fungal co-infection, viremia at higher levels (>10⁴ copies/mL) was documented in patients without evidence for other infections, raising the possibility that at least in some instances the onset of fever may have been attributable to the virus detected. The observations suggest that viral infections, potentially resulting from reactivation, might also play a clinically relevant role in patients receiving chemotherapy for treatment of malignant neoplasms, and routine screening for viremia in this clinical setting might be warranted.

Seroprevalence and trends of transfusion transmissible infections among retrospective blood donors in Western Azerbaijan Regional Blood Transfusion Center, Iran: A ten-years evaluation

Transfusion transmissible infections (TTIs) have been a public health challenge for the accessibility, quality and safety of blood transfusion. The present study aimed to consider the prevalence and the trends of hepatitis B virus (HBV), hepatitis C virus (HCV), Human T-cell leukemia virus type 1 (HTLV-1), human immunodeficiency virus (HIV) and syphilis across the ten years among retrospective blood donors. A retrospective investigation of blood donors' data covering the period from 22 May 2009 to 22 May 2019 was done. Data was accumulated and analyzed from Blood Transfusion Center records, pertaining to all donors who were screened for various TTIs using respective immunological techniques. Out of the 682,171 screened donors in the 2009-2019 study period, 2470 (0.36 %) were infected with at least one infectious agent. The overall prevalence of HBV, HCV, HTLV-1, HIV and syphilis were 1700 (0.25 %), 184 (0.027 %), 335 (0.05 %), 4 (0.0.05 %) and 247 (0.036 %), respectively. The study showed male dominated donor pool (96.79 %) with higher prevalence (0.34 %) of TTIs compared to female donors (0.02 %) with 3.21 % population. Despite the low prevalence of TTIs in our study, HBV, HCV, syphilis and HIV have remained a big threat to safe blood transfusion in Iran. Strict adherence to selection criteria, algorithm of donor screening, use of highly sensitive and specific methods for detection of TTIs, regular consultation and health education programs, prevention and sanitization strategies to reduce the risk of TTIs are recommended to reduce the risk of TTIs and ensure the safety of blood transfusion for recipient.

Impact of pathogen reduction methods on immunological properties of the COVID-19 convalescent plasma

BACKGROUND AND OBJECTIVES

COVID-19 convalescent plasma is an experimental treatment against SARS-CoV-2. The aim of this study is to assess the impact of different pathogen reduction methods on the levels and virus neutralizing activity of the specific antibodies against SARS-CoV2 in convalescent plasma.

MATERIALS AND METHODS

A total of 140 plasma doses collected by plasmapheresis from COVID-19 convalescent donors were subjected to pathogen reduction by three methods: methylene blue (M)/visible light, riboflavin (R)/UVB and amotosalen (A)/UVA. To conduct a paired comparison, individual plasma doses were divided into 2 samples that were subjected to one of these methods. The titres of SARS-CoV2 neutralizing antibodies (NtAbs) and levels of specific immunoglobulins to RBD, S- and N-proteins of SARS-CoV-2 were measured before and after pathogen reduction.

RESULTS

The methods reduced NtAbs titres differently: among units with the initial titre 80 or above, 81% of units remained unchanged and 19% decreased by one step after methylene blue; 60% were unchanged and 40% decreased by one step after amotosalen; after riboflavin 43% were unchanged and 50% (7%, respectively) had a one-step (two-step, respectively) decrease. Paired two-sample comparisons (M vs. A, M vs. R and A vs. R) revealed that the largest statistically significant decrease in quantity and activity of the specific antibodies resulted from the riboflavin treatment.

CONCLUSION

Pathogen reduction with methylene blue or with amotosalen provides the greater likelihood of preserving the immunological properties of the COVID-19 convalescent plasma compared to riboflavin.

A restrictive versus liberal transfusion strategy to prevent myocardial injury in patients undergoing surgery for fractured neck of femur: a feasibility randomised trial (RESULT-NOF)

BACKGROUND

The optimum transfusion strategy in patients with fractured neck of femur is uncertain, particularly if there is coexisting cardiovascular disease.

METHODS

We conducted a prospective, single-centre, randomised feasibility trial of two transfusion strategies. We randomly assigned patients undergoing surgery for fractured neck of femur to a restrictive (haemoglobin, 70-90 g L-1) or liberal (haemoglobin, 90-110 g L-1) transfusion strategy throughout their hospitalisation. Feasibility outcomes included: enrolment rate, protocol compliance, difference in haemoglobin, and blood exposure. The primary clinical outcome was myocardial injury using troponin estimations. Secondary outcomes included major adverse cardiac events, postoperative complications, duration of hospitalisation, mortality, and quality of life.

RESULTS

We enrolled 200 (22%) of 907 eligible patients, and 62 (31%) showed decreased haemoglobin (to 90 g L-1 or less) and were thus exposed to the intervention. The overall protocol compliance was 81% in the liberal group and 64% in the restrictive group. Haemoglobin concentrations were similar preoperatively and at postoperative day 1 but lower in the restrictive group on day 2 (mean difference [MD], 7.0 g L-1; 95% confidence interval [CI], 1.6-12.4). Lowest haemoglobin within 30 days/before discharge was lower in the restrictive group (MD, 5.3 g L-1; 95% CI, 1.7-9.0). Overall, 58% of patients in the restrictive group received no transfusion compared with 4% in the liberal group (difference in proportion, 54.5%; 95% CI, 36.8-72.2). The proportion with the primary clinical outcome was 14/26 (54%, liberal) vs 24/34 (71%, restrictive), and the difference in proportion was -16.7% (95% CI, -41.3 to 7.8; P=0.18).

CONCLUSION

A clinical trial of two transfusion strategies in hip fracture with a clinically relevant cardiac outcome is feasible.

CLINICAL TRIAL REGISTRATION

NCT03407573.

Plasma-based COVID-19 treatments in low- and middle-income nations pose a high risk of an HIV epidemic

Convalescent plasma therapy holds promise as a transient treatment for COVID-19. Yet, blood products are important sources of HIV infection in low- and middle-income nations. Great care must be taken to prevent plasma therapy from fueling HIV epidemics in the developing world.

The seropervelance of infectious hepatitis viruses (HBV, HCV and HEV) among blood donors and their correlation to risk factors in Qena governorate, Upper Egypt

This study was performed to determine the prevalence of HBV and HCV infection among blood donors and the occurrence of HEV in hepatitis viruses seropositive blood donors. Also, to investigate the correlation between the occurrence of hepatitis viruses and other risk factors (gender, age, occupation, educational level, residency and donors' types). A total of 11,604 blood samples from apparently healthy blood donors of age range 18-60 years old were collected. The blood donors were categorized as voluntary and replacement donors. Blood samples from donors were tested for the presence of HBsAg, HCV and HEV antibodies by using Enzyme-linked immunosorbent assay. The overall results indicated that 671 out of 11,604 blood donors; 370 persons (3.188%) HCV, 295 persons (2.542%) HBV and 6 persons (0.052%) HCV and HBV; were hepatitis viruses seropositive donors. The prevalence of HEV were 193 (28.76%) among these seropositive blood donors. There is a highly significant correlation among HCV, HBV and other risk factors. Also, the HEV showed high significant with age and educational level and significant with donor types and locations. All investigated virus combinations (HEV/HCV, HEV/HBV and HEV/HCV/HBV) were highly significant with the risk factors except for occupation. In conclusion, the HEV is significantly correlated to HCV and HBV seropositive donors and should be screened among blood donors.

Patient and family experience with chronic transfusion therapy for sickle cell disease: A qualitative study

Background

There is a limited understanding of the patient and family experience of Chronic Transfusion Therapy (CTT) for prevention of complications of Sickle Cell Disease (SCD). We sought to understand patient and family experience with CTT using qualitative methods.

Methods

Fifteen parents of children < 18 years old and nine children 12–18 years old with SCD who were receiving CTT for > 1 year were interviewed using a semi-structured interview format, and interviews were analyzed using open coding methods.

Results

Four themes created a narrative of the patient and family experience of CTT: 1) Burden of CTT, 2) Coping with CTT, 3) Perceived benefits and risks of CTT, and 4) Decision making regarding CTT. Participants reported substantial burden of CTT, including the impact of CTT on daily life and family, distress about venous access, burden of chelation therapy, and anxiety about CTT complications. Participants described how they coped with CTT. Participants reported increased energy, decreased pain, fewer hospitalizations, and stroke prevention with CTT, but also recognized complications of CTT, though awareness was limited in adolescents. Parents described sharing in the informed decision-making process with their healthcare provider about CTT, but adolescent patient participants reported that they were not involved in this process.

Conclusions

CTT is associated with significant patient and family burden. Support from family, healthcare providers and school may help individuals cope with some of this burden. These findings provide the basis for future studies to identify strategies to mitigate the burden of CTT and improve the patient experience with this therapy. Future studies should also systematically assess patient knowledge about the key components of CTT and chelation using quantitative assessments.

Challenges to improving patient outcome following massive transfusion in severe trauma

Introduction: Uncontrolled hemorrhage with trauma-induced coagulopathy (TIC) still represents the most common cause of preventable death after trauma. Timely diagnosis and treatment including bleeding control and hemostatic resuscitation to correct TIC are important, as death from exsanguination occurs rapidly. Recognizing who requires an early massive transfusion together with the initiation of corresponding massive transfusion protocols (MTPs) is key to outcome.Areas covered: This expert review summarizes the current state of MT including the activation and termination of MTPs, complications of MT, and strategies for refinement in the administration of blood products in order to avoid harmful over-transfusion.Expert opinion: MTPs should be initiated and continued until normal physiologic parameters are reached and definitive control of bleeding is achieved. Hospitals should develop their own MTPs, guided by evidence, and according to local infrastructure, logistics, needs and patient populations. Massive transfusion, defined as > 10 units of packed red blood cell concentrates (pRBCs) within the first 24 hours of hospital admission, can be life-saving, but is not without complications. MTPs are currently being refined through targeted and early goal-directed approaches which include functional coagulation testing assays to better guide the administration of blood products and hemostatic agents once the patient is stabilized.

Preclinical safety assessment of pathogen reduced red blood cells treated with amustaline and glutathione

BACKGROUND

The nucleic acid targeted pathogen reduction (PR) system utilizing amustaline (S-303) and glutathione (GSH) is designed to inactivate blood-borne pathogens and leukocytes in red blood cell concentrates (PR-RBCC). Inactivation is attained after amustaline intercalates and forms covalent nucleic acid adducts preventing replication, transcription, and translation. After pathogen inactivation, amustaline spontaneously hydrolyzes to S-300, the primary negatively charged reaction product; amustaline is below quantifiable levels in PR-RBCC. GSH quenches free unreacted amustaline.

STUDY DESIGN AND METHODS

The genotoxic and carcinogenic potential of PR-RBCC, the reaction by-products, and S-300 were assessed in accordance with the International Conference on Harmonization (ICH) guidelines and performed in compliance with the Food and Drug Administration (FDA) good laboratory practice standards, 21 CFR Part 58. in vitro bacterial reverse mutagenicity and chromosomal aberration assays were performed with and without exogenous S9 metabolic activation, and in in vivo clastogenicity and carcinogenic assays using validated murine models.

RESULTS

PR-RBCCs were not genotoxic in vitro and in vivo and were non-carcinogenic in p53+/- transgenic mice transfused over 26 weeks. Estimated safety margins for human exposure ranged from >90 to >36 fold for 2 to 5 PR-RBCCs per day, respectively. PR-RBCCs and S-300 did not induce chromosome aberration in the in vivo murine bone marrow micronucleus assay at systemically toxic doses.

CONCLUSIONS

PR-RBCCs did not demonstrate genotoxicity in vitro or in vivo and were not carcinogenic in vivo. These studies support the safety of PR-RBCCs and suggest that there is no measurable genotoxic hazard associated with transfusion of PR-RBCCs.

The type-reproduction number of sexually transmitted infections through heterosexual and vertical transmission

Multiple sexually transmitted infections (STIs) have threatened human health for centuries. Most STIs spread not only through sexual (horizontal) transmission but also through mother-to-child (vertical) transmission. In a previous work (Ito et al. 2019), we studied a simple model including heterosexual and mother-to-child transmission and proposed a formulation of the basic reproduction number over generations. In the present study, we improved the model to take into account some factors neglected in the previous work: adult mortality from infection, infant mortality caused by mother-to-child transmission, infertility or stillbirth caused by infection, and recovery with treatment. We showed that the addition of these factors has no essential effect on the theoretical formulation. To study the characteristics of the epidemic threshold, we derived analytical formulas for three type-reproduction numbers for adult men, adult women and juveniles. Our result indicates that if an efficient vaccine exists for a prevalent STI, vaccination of females is more effective for containment of the STI than vaccination of males, because the type-reproduction number for adult men is larger than that for adult women when they are larger than one.

Photodynamic Inactivation of Candida albicans in Blood Plasma and Whole Blood

The few approved disinfection techniques for blood derivatives promote damage in the blood components, representing risks for the transfusion receptor. Antimicrobial photodynamic therapy (aPDT) seems to be a promising approach for the photoinactivation of pathogens in blood, but only three photosensitizers (PSs) have been approved, methylene blue (MB) for plasma and riboflavin and amotosalen for plasma and platelets. In this study, the efficiency of the porphyrinic photosensitizer Tri-Py(+)-Me and of the porphyrinic formulation FORM was studied in the photoinactivation of Candida albicans in plasma and in whole blood and the results were compared to the ones obtained with the already approved PS MB. The results show that FORM and Tri-Py(+)-Me are promising PSs to inactivate C. albicans in plasma. Although in whole blood the inactivation rates obtained were higher than the ones obtained with MB, further improvements are required. None of these PSs had promoted hemolysis at the isotonic conditions when hemolysis was evaluated in whole blood and after the addition of treated plasma with these PSs to concentrates of red blood cells.

Computer algorithm can match physicians' decisions about blood transfusions

BACKGROUND

Checking appropriateness of blood transfusion for quality assurance required enormous usage of time and human resources from the healthcare system. We report here a new machine learning algorithm for checking blood transfusion quality.

MATERIALS AND METHODS

The multilayer perceptron neural network (MLPNN) was designed to learn an expert's judgement from 4946 clinical cases. The accuracy in predicting the blood transfusion was then reported.

RESULTS

We achieved a 96.8% overall accuracy rate, with a 99% match rate to the experts' judgement on those appropriate cases and 90.9% on the inappropriate cases.

CONCLUSIONS

Machine learning algorithm can accurately match to human judgement by feeding in pre-surgical information and key laboratory variables.

Blood utilisation and transfusion reactions in adult patients transfused with conventional or pathogen-reduced platelets

Pathogen-reduced (PR) platelets are routinely used in many countries. Some studies reported changes in platelet and red blood cell (RBC) transfusion requirements in patients who received PR platelets when compared to conventional (CONV) platelets. Over a 28-month period we retrospectively analysed platelet utilisation, RBC transfusion trends, and transfusion reaction rates data from all transfused adult patients transfused at the Yale-New Haven Hospital, New Haven, CT, USA. We determined the number of RBC and platelet components administered between 2 and 24, 48, 72 or 96 h. A total of 3767 patients received 21 907 platelet components (CONV = 8912; PR = 12 995); 1,087 patients received only CONV platelets (1578 components) and 1,466 patients received only PR platelets (2604 components). The number of subsequently transfused platelet components was slightly higher following PR platelet components (P < 0·05); however, fewer RBCs were transfused following PR platelet administration (P < 0·05). The mean time-to-next platelet component transfusion was slightly shorter following PR platelet transfusion (P = 0·002). The rate of non-septic transfusion reactions did not differ (all P > 0·05). Septic transfusion reactions (N = 5) were seen only after CONV platelet transfusions (P = 0·011). These results provide evidence for comparable clinical efficacy of PR and CONV platelets. PR platelets eliminated septic transfusion reactions without increased risk of other types of transfusions with only slight increase in platelet utilisation.

Splenic infarction in babesiosis: A rare presentation

Babesiosis is a protozoan parasitic infection transmitted by the Ixodes tick. Splenic infarction is a rare, but potentially life-threatening complication of babesiosis; it is therefore vital that this complication is recognized.

Current Advances in Red Blood Cell Generation Using Stem Cells from Diverse Sources

Blood transfusions hold an indispensable part in the modern healthcare system. Up to date, the blood supply is largely dependent on donations. Unfortunately, collecting the clinical-grade blood products has become a challenging mission due to accelerated population aging, which not only increases the need for blood transfusions but also decreases the number of healthy donors. Moreover, individuals with severe hematological abnormalities or rare blood phenotypes need alternative therapeutic approaches instead of conventional blood transfusion. In these aspects, the concept of in vitro/ex vivo production of blood cells has been emerging and many attempts have been focused on manufacturing mature erythrocytes, so-called red blood cells (RBCs), the most common and important component among the blood derivatives. In this review, we provide a general overview regarding the current strategies for generating RBCs from various stem cell sources including pluripotent stem cells (PSCs) as well as circulating blood stem cells and the remaining challenges that must be overcome prior to their practical application.

Cold agglutinin disease and its implications for dental treatment

Cold agglutinin disease (CAD) is a rare variant of autoimmune hemolytic anemia, characterized by the destruction of red blood cells by autoantibodies following exposure to cold temperatures. This case is of a 75-year-old male who presented to a dedicated hematology dental clinic. The dental management over a 3-year period is described, whereby the patient had extraction and periodontal disease management with considerations for medical, social and dental risk assessments and treatment modifications. The principles are applicable to patients with other hematological disorders.

Prevalence and Trends of Major Transfusion Transmissible Infections among Blood Donors in Dire Dawa Blood bank, Eastern Ethiopia: Retrospective Study

Background

Acquisition of transfusion transmissible infections in the process of therapeutic blood transfusion is a major global health challenge in transfusion medicine. This study aimed to determine the prevalence and trends of major transfusion transmissible infections among blood donors.

Method

A retrospective analysis of consecutive blood donors' records covering the period between July 2010 and June 2013 was conducted at Dire Dawa Blood Bank, Eastern Ethiopia.

Result

A total of 6376 blood donors were tested, out of which 5647(88.57%) were replacement donors and 729(11.43%) were voluntary donors. The majority of them were male, 5430(85.16%), and aged between 18–32 years, 4492(70.45%). A total of 450(7.06%) donors had serological evidence of infection with at least one pathogen. The overall positivity rates of HBV, HIV, HCV and syphilis were 4.67%, 1.24%, 0.96%, and 0.44% respectively. Trends for transfusion-transmissible infections showed a significant decrease from 9.51% in 2010 to 6.95% in 2013 with the least prevalence in 2012 (5.90%) (P = 0.004). The prevalence of transfusion transmissible infections was significantly higher among male blood donors compared to female donors, among the age group of 25–32 years and 33–40 years compared to the age group of 18–24 years old, and among unemployed and private workers compared to students.

Conclusion

A significant percentage of the blood donors harbor transfusion-transmissible infections. Stringent donor selection using standard methods is highly recommended to ensure the safety of blood for the recipient. Furthermore, efforts on motivating and creating awareness in the community are required to increase voluntary blood donors.

Transfusion-Transmitted Infections Reported to the National Healthcare Safety Network Hemovigilance Module

Transfusion-transmitted infections (TTIs) can be severe and result in death. Transfusion-transmitted viral pathogen transmission has been substantially reduced, whereas sepsis due to bacterial contamination of platelets and transfusion-transmitted babesiosis may occur more frequently. Quantifying the burden of TTI is important to develop targeted interventions. From January 1, 2010, to December 31, 2016, health care facilities participating in the National Healthcare Safety Network Hemovigilance Module monitored transfusion recipients for evidence of TTI and recorded the total number of units transfused. Facilities use standard criteria to report TTIs. Incidence rates of TTIs, including for bacterial contamination of platelets and transfusion-transmitted babesiosis, are presented. One hundred ninety-five facilities reported 111 TTIs and 7.9 million transfused components to the National Healthcare Safety Network Hemovigilance Module. Of these 111 reports, 54 met inclusion criteria. The most frequently reported pathogens were Babesia spp in RBCs (16/23, 70%) and Staphylococcus aureus in platelets (12/30, 40%). There were 1.95 (26 apheresis, 4 whole blood derived) TTIs per 100 000 transfused platelet units and 0.53 TTI per 100 000 transfused RBC components, compared to 0.68 TTI per 100 000 all transfused components. Bacterial contamination of platelets and transfusion-transmitted babesiosis were the most frequently reported TTIs. Interventions that reduce the burden of bacterial contamination of platelets, particularly collected by apheresis, and Babesia transmission through RBC transfusion would reduce transfusion recipient morbidity and mortality. These analyses demonstrate the value and importance of facility participation in national recipient hemovigilance using standard reporting criteria.

Laboratory diagnosis for thalassemia intermedia: Are we there yet?

BACKGROUND

Differentiation between thalassemia major and thalassemia intermedia at presentation is not uniformly characterized, for which an absolute criteria needs to be developed. This study investigated the primary and secondary genetic modifiers to develop a laboratory finding by forming different genetic mutational combinations seen among thalassemia intermedia patients and comparing them with thalassemia major.

METHODS

This cross-sectional study analyzed 315 thalassemia intermedia patients. One hundred and five thalassemia major patients were recruited on the basis of documented evidence of diagnosis and were receiving blood transfusion therapy regularly. Various mutational combinations were identified, and comparison was performed between thalassemia intermedia and major using statistical software STATA 11.1.

RESULTS

The mean age of the total population was 5.9 ± 5.32 years of which 165 (52%) were males. Of the two groups (thalassemia intermedia and thalassemia major), IVSI-5, IVSI-1, and Fr 8-9 were more prevalent among the thalassemia intermedia cohort. When comparison was performed between the thalassemia intermedia and thalassemia major patients, it showed significant results for the presence of Xmn-1 polymorphism.

CONCLUSION

The presence of IVSI-5 homozygous with Xmn-1, IVSI-5 heterozygous with Xmn-1, Cd 30 homozygous with or without Xmn-1 and IVSI-1 homozygous or heterozygous either with or without Xmn-1 prove to be strong indicators towards diagnosis of thalassemia intermedia.

Budget impact of implementing platelet pathogen reduction into the Italian blood transfusion system

BACKGROUND

Despite improvements in blood donor selection and screening procedures, transfusion recipients can still develop complications related to infections by known and emerging pathogens. Pathogen reduction technologies (PRT) have been developed to reduce such risks. The present study, developed whithin a wider health technology assessment (HTA) process, was undertaken to estimate the costs of the continuing increase in the use of platelet PRT in Italy.

MATERIALS AND METHODS

A multidisciplinary team was established to perform the HTA and conduct a budget impact analysis. Quantitative data on platelet use were derived from the 2015 national blood transfusion report and from the Italian Platelets Transfusion Assessment Study (IPTAS). The current national fee of 60 Euro per platelet PRT procedure was used to quantify the costs to the Italian National Health Service (INHS). The analysis adopts a 3-year time-frame. In order to identify the impact on budget we compared a scenario representing an increased use of PRT platelets over time with a control scenario in which standard platelets are used.

RESULTS

Progressive implementation of PRT for 20%, 40% and 66% of annual adult platelet doses could generate an increase in annual costs for the INHS amounting to approximately 7, 14 and 23 million Euros, respectively. Use of kits and devices suitable for the treatment of multiple adult platelet doses in one PRT procedure could lower costs.

DISCUSSION

In order to fully evaluate the societal perspective of implementing platelet PRT, the increase in costs must be balanced against the expected benefits (prevention of transfusion-transmissible infections, white cell inactivation, extension of platelet storage, discontinuation of pathogen detection testing). Further studies based on actual numbers of platelet transfusion complications and their societal cost at a local level are needed to see the full cost to benefit ratio of platelet PRT implementation in Italy, and to promote equal treatment for all citizens.

Comparison of Decompression, Decompression Plus Fusion, and Decompression Plus Stabilization for Degenerative Spondylolisthesis: A Prospective, Randomized Study

STUDY DESIGN

This is a prospective, randomized controlled trial.

OBJECTIVE

To prospectively assess the long-term clinical results of decompression alone, decompression plus fusion, and decompression plus stabilization for degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Symptoms of lumbar spinal stenosis due to degenerative spondylolisthesis originate from compression of the dural sac or nerve root. Essentially, this condition is treated by performing a decompression of neural structures. Posterolateral lumbar fusion and posterior pedicle-based dynamic stabilization are additional techniques performed to ensure improved prognosis. However, to date, the selection of a surgical procedure for lumbar spinal stenosis due to degenerative spondylolisthesis remains debatable, especially in terms of the addition of instrumentation because of the few available prospective, randomized studies.

MATERIALS AND METHODS

We randomly assigned patients who had 1 level lumbar spinal stenosis due to degenerative spondylolisthesis at the L4/5 level to undergo either decompression alone (decompression group), decompression plus fusion (fusion group), or decompression plus stabilization (stabilization group). Outcomes were assessed using the Japanese Orthopaedic Association and Visual Analogue Scale scores.

RESULTS

In total, 85 patients underwent randomization. The follow-up rate at 5 years was 86.4%. The fusion and stabilization groups showed higher blood loss and a longer operative time than the decompression group. The fusion group showed longer postoperative hospital stay than the decompression group. In terms of clinical outcomes, all scores significantly improved postoperatively, and these outcomes were maintained at 5 years postoperatively in each group. There were no significant differences among the groups at 1 and 5 years postoperatively.

CONCLUSIONS

Additional instrumentation operation for low-grade (<30%) degenerative spondylolisthesis did not result in superior results to decompression alone at 1 and 5 years postoperatively.

LEVEL OF EVIDENCE

Level II.

Cost estimate of platelet transfusion in the United States for patients with chronic liver disease and associated thrombocytopenia undergoing elective procedures

AIMS

This study aimed to estimate the cost of platelet transfusion in patients with chronic liver disease (CLD)-associated thrombocytopenia undergoing an elective procedure in the United States.

MATERIALS AND METHODS

The study was conducted in two parts: development of a conceptual framework identifying direct, indirect and intangible costs of platelet transfusion, followed by the estimation of the total cost of platelet transfusion in patients with CLD-associated thrombocytopenia before an elective procedure in the United States using the conceptual framework and cost data obtained from a literature search. The cost of the entire care required to raise a patient's platelet count before the procedure was considered.

RESULTS

The final conceptual framework included the costs of generating the supply of platelets, the platelet transfusion itself, adverse events associated with platelet transfusion and refractoriness to platelet transfusion. When costs were accounted for in all the framework cost categories, the total direct cost of a platelet transfusion in a patient with CLD and associated thrombocytopenia was estimated to be in the range of $5258 to $13,117 (2017 US dollars) in the United States. The largest portion of costs was incurred by the transfusion event itself ($3723 to $4436) and the cost of refractoriness ($874 to $7578), which included the opportunity cost of a delayed procedure and subsequent platelet transfusions with human leukocyte antigen-matched platelets.

LIMITATIONS AND CONCLUSIONS

Although we were unable to include all cost components identified in the conceptual framework in our total cost estimate, thus likely underestimating the true total cost, and despite the data gaps and challenges limiting our estimate of the full cost of a platelet transfusion in patients with CLD-associated thrombocytopenia undergoing an elective procedure in the United States, this study outlines a comprehensive conceptual framework for estimating the cost elements of a platelet transfusion in these patients.

Light-based methods for whole blood bacterial inactivation enabled by a recirculating flow system

Light of certain wavelengths can be used to inactivate pathogens. Whole blood is opaque; thus, the penetration of light is reduced. Here, we overcame this limitation using a thin transparent tube that is illuminated from all angles. Three light-based techniques were evaluated: photodynamic therapy (PDT) using a 660-nm light and antibody-photosensitizer conjugates, ultraviolet, and violet light. We observed a reduction of 55-71% of Staphylococcus aureus after 5 h of exposure (starting concentration 107  CFU mL-1 ) and an 88-97% reduction in methicillin-resistant Staphylococcus aureus (MRSA) (starting 104  CFU mL-1 ). An 83-92% decrease for S. aureus and 98-99.9% decrease for MRSA were observed when combined with an immunocapture approach. Complete blood count with differential analysis did not reveal any significant changes in the blood cell numbers. Genotoxicity studies showed that violet and ultraviolet did not induce any significant level of single strand breaks and alkali labile sites in the peripheral blood mononuclear cells (PBMC). In contrast, ultraviolet did induce a very low level of cyclobutane pyrimidine dimers, a UV damage indicator. PDT generated a significant level of single strand breaks and 8-oxoGua in these cells. The approaches showed promise for whole blood pathogen inactivation with minimal collateral damage to PBMC.

Prevalence and risk factors of HTLV-1/2 and other blood borne infectious diseases among blood donors in Yaounde Central Hospital, Cameroon

Introduction

Transfusion-transmissible infectious microorganisms including bacteria and viruses are among the greatest threats to blood safety for the recipient. The prevalence and risk factors of HTLV-1/2 and other blood borne infectious diseases were determined among blood donors in Yaounde Central Hospital, Cameroon.

Methods

Design: cross sectional study. Setting: The blood bank unit of Yaounde Central Hospital, Cameroon. Subjects: a consecutive sample of 265 apparently healthy adult blood donors. Investigations: Search for the presence of hepatitis B surface antigen (AgHBs) and antibodies to human T-lymphotropic virus type 1 (anti-HTLV-1/2), human immunodeficiency virus (anti-HIV), hepatitis C virus (anti-HCV) and syphilis and to determine the epidemiological correlates, if any, in the occurrence of HTLV infection.

Results

77 (29.05%) of the blood donors had serological evidence of infection with at least one pathogen and 4 (5.2%) had dual infections with HTLV-1/2. The overall prevalence of HTLV-1/2, HIV, HCV, HBV and syphilis were 5.7%, 5.3%, 2.6%, 11.7%, 3.8% respectively. Surgical history (Chi²=4.785; P=0.029), scarification (Chi²=6.359; P = 0.012), piercing (Chi² = 16.353; P = 0.000) and intravenous drug use (Chi² = 15.660; P = 0.000) were identified as risk factors for HTLV-1/2 infection.

Conclusion

A relative high prevalence of viral infections and syphilis was recorded among the study participants especially for HTLV-1/2 for which none blood donation is routine screened in our set up. Therefore, a routine screen of blood prior to transfusion should include anti-HTLV-1/2 tests.

Therapeutics incorporating blood constituents

Blood deficiency and dysfunctionality can result in adverse events, which can primarily be treated by transfusion of blood or the re-introduction of properly functioning sub-components. Blood constituents can be engineered on the sub-cellular (i.e., DNA recombinant technology) and cellular level (i.e., cellular hitchhiking for drug delivery) for supplementing and enhancing therapeutic efficacy, in addition to rectifying dysfunctioning mechanisms (i.e., clotting). Herein, we report the progress of blood-based therapeutics, with an emphasis on recent applications of blood transfusion, blood cell-based therapies and biomimetic carriers. Clinically translated technologies and commercial products of blood-based therapeutics are subsequently highlighted and perspectives on challenges and future prospects are discussed.

STATEMENT OF SIGNIFICANCE

Blood-based therapeutics is a burgeoning field and has advanced considerably in recent years. Blood and its constituents, with and without modification (i.e., combinatorial), have been utilized in a broad spectrum of pre-clinical and clinically-translated treatments. This review article summarizes the most up-to-date progress of blood-based therapeutics in the following contexts: synthetic blood substitutes, acellular/non-recombinant therapies, cell-based therapies, and therapeutic sub-components. The article subsequently discusses clinically-translated technologies and future prospects thereof.

Transfusion Medicine and Molecular Genetic Methods

Transfusion procedures are always complicated by potential genetic mismatching between donor and recipient. Compatibility is determined by several major antigens, such as the ABO and Rhesus blood groups. Matching for other blood groups (Kell, Kidd, Duffy, and MNS), human platelet antigens, and human leukocyte antigens (HLAs) also contributes toward the successful transfusion outcomes, especially in multitransfused or highly immunized patients. All these antigens of tissue identity are highly polymorphic and thus present great challenges for finding suitable donors for transfusion patients. The ABO blood group and HLA markers are also the determinants of transplant compatibility, and mismatched antigens will cause graft rejection or graft-versus-host disease. Thus, a single and comprehensive registry covering all of the significant transfusion and transplantation antigens is expected to become an important tool in providing an efficient service capable of delivering safe blood and quickly locating matching organs/stem cells. This review article is intended as an accessible guide for physicians who care for transfusion-dependent patients. In particular, it serves to introduce the new molecular screening methods together with the biology of these systems, which underlies the tests.