Adult Blood Donors Research Articles

Alexithymia and estimated 10-year cardiovascular disease risk in healthy adults: a community-based cross-sectional study

BackgroundThis cohort study aimed to explore whether and to what extent alexithymia would be associated with cardiovascular disease (CVD) risk over an estimated 10-year period, over and above established clinical cofactors (i.e., depressive symptoms, quality of life, sociodemographic, anthropometric, lifestyle, and biological data), in a low-risk population of blood donors.MethodsA sample of 1,021 adult Italian blood donors (age 46.9 ± 8.39; 61.2% men) was consecutively recruited. The 10-year-CVD risk score was estimated using the CUORE risk score (CRS). Sociodemographic, lifestyle, anthropometric, biological, and psychological (i.e., quality of life, depressive symptoms, and alexithymia) CVD risk data were assessed using validated self-report measures or clinical records.ResultsAs expected, most participants (78.5%) had a low CVD risk (CRS < 3%) and an overall low-risk profile for all the parameters. Compared with subjects at low risk of CVD (n = 911, 78.5%), those with high risk (i.e., rated ≥3 on CUORE risk assessment; n = 250, 21.5%) reported higher levels of alexithymia (p < 0.001). Subjects with higher alexithymia (n = 236, 23.1%) reported higher levels of psychosocial impairment, depressive symptoms, and biological risk variables for CVD. Alexithymia was significantly associated with 10-year CVD risk (OR = 1.02, 95% CI = 1.01–1.04, p = 0.009), even after adjusting for key sociodemographic and clinical risk variables.ConclusionAlthough limited by the cross-sectional design, this study is the first to show that alexithymia leads to a higher risk for 10-year CVD estimate in healthy subjects with low-risk profile, regardless of known biomarkers and traditional CVD risk factors.

Quality and stability studies of red blood cell concentrates from umbilical cord blood compared to their adult counterparts.

Prematurity is a significant health issue due to its incidence and associated complications. Anemia is common in extremely preterm infants (EPI) and often requires transfusions. Red blood cells (RBC) from adult blood (AB) donors have been linked to oxygen-related complications in EPI, leading to the exploration of cord blood (CB) as an alternative source. However, standardization of CB-RBC manufacturing and comparison with AB-RBC characteristics are necessary before clinical studies can be conducted. This study investigated the quality and characteristics of leukoreduced, gamma-irradiated CB-RBC obtained using a commercial closed system from CB donations not meeting hematopoietic transplantation criteria. CB-RBC units were compared with AB-RBC units, both stored in saline-adenine-glucose-mannitol (SAGM). Various parameters, including hematological and biochemical characteristics, pH, 2,3-DPG levels, blood gases and potential toxicants, were evaluated during storage. CB-RBC units had acceptable initial quality parameters and a hematocrit (55±2%) comparable to AB-RBC. The main finding during storage was a faster rise in hemolysis compared to AB-RBC. Potassium (K+) significantly increased during storage in both sources. As expected, glucose levels decreased, and conversely, lactate levels increased, indicating similar patterns of anaerobic glycolysis during storage. pH decreased, affecting the oxygen dissociation curve due to reduced 2,3-DPG levels. After irradiation at 14 days of storage, CB-RBC were less stable as hemolysis and K+ significantly increased compared to AB-RBC at 24 hours. Phthalate concentrations, indicative of plasticizers, increased during storage, but significantly less in CB compared to AB-RBC. Most metals measured were within acceptable ranges. The quality of CB-RBC during storage is primarily influenced by levels of hemolysis and extracellular K+ content. Based on the analyzed parameters, we suggest that the expiration date for CB-RBC stored with SAGM should be set at 14 days, with transfusion occurring within <24 hours after irradiation.

Hemoglobin Electrophoresis versus Kleihauer-Betke to Determine Bone Marrow Suppression in Fetuses Undergoing Intrauterine Transfusion.

Mainstay therapy for fetuses affected by maternal red cell alloimmunization is serial intrauterine transfusion (IUT). Testing to determine when fetal red cells have been replaced with donor cells historically involves the use of the Kleihauer-Betke (KB) test. Hemoglobin (Hgb) electrophoresis testing may be more rapid with a reduced cost of analysis. We aimed to determine the correlation between fetal Hgb electrophoresis versus the traditional KB test. This is a retrospective analysis of all alloimmunized singleton pregnancies undergoing IUT between January 1, 2021, and July 1, 2023. Maternal and fetal characteristics were collected along with the indication for IUT. A final fetal blood sample was obtained at the conclusion of each transfusion and sent for KB testing and Hgb electrophoresis. The primary outcome was the assessment of these parameters in their ability to predict the replacement of the fetal circulating red cell population with donor cells. Linear regression analysis and repeated measures analysis of variance were performed, and p-values less than 0.05 were considered significant. A total of 56 IUTs were performed in 16 patients. There were 39 (69.6%) final KB test values collected and compared with 30 (53.6%) final Hgb electrophoresis values. Hgb electrophoresis when compared with the KB test demonstrated a significant correlation (R 2 = 0.93; 95% confidence interval, 0.61-0.76; p < 0.001). This same finding held true when examining the correlation at each individual IUT as well. The final KB test and Hgb electrophoresis values significantly decreased with each transfusion (p = 0.003). A predominance of adult donor blood was noted by the third transfusion for both laboratory indices. Fetal Hgb electrophoresis obtained at the time of IUT demonstrates a significant correlation with the traditional KB test. · Fetal Hgb electrophoresis following IUT is underexplored. · Hgb electrophoresis is an automated evaluation. · The traditional KB test is a manual evaluation. · These two tests demonstrate significant correlation.

Impact of Mild SARS-CoV-2 Infection on Hematological Parameters and Suitability of Apheresis Platelets Donation in Blood Donors

To investigate the effects of mild SARS-CoV-2 infection on hematological parameters of adult blood donors and the suitability of apheresis platelet donation, the changes of the hematological parameters in blood donors with mild infection of the SARS-CoV-2 Omicron variant strain were evaluated. Seventy-two blood donors with mild COVID-19 symptoms who donated consecutive apheresis platelets for 3 times from December 2022 to January 2023, 42 cases among which were included in the infection-positive group, and 30 cases in the suspected infection group. Forty-two donors un-vaccinated against SARS-CoV-2, un-infected, and donated three consecutive apheresis platelets from October to November 2022 were included in the control group. The changes of blood routine testing in the positive group and the suspected infection group were retrospectively compared before (Time1) and after (Time2 and Time3) the onset of symptoms, three consecutive times (Time1, Time2, Time3) in the control group by repeated measures analysis of variance. The Bayesian discriminant method was used to establish a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not. Simple effect of the number times of tests in the positive and suspected infection groups was significant（ Finfection-positive group=6.98, P < 0.001, partial η2=0.79, Fsuspected infection group=4.31, P < 0.001, partial η2=0.70）. The positive group and the suspected infection group had lower RBC, HCT, and HGB, and higher PLT and PCT at Time2 compared to Time1 and Time3(P < 0.05). The positive group and the suspected infection group showes RDW-CV and RDW-SD at Time3 higher than Time1 and Time2 (P < 0.001). The simple effect of the number times of tests in the control group was not significant ( F=0.96, P =0.55, partial η2=0.34). The difference of the whole blood count parameters in the control group for three times was not statistically significant (P >0.05). We established a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not. The equation had an eigenvalue of 0.22, a canonical correlation of 0.43 (χ2=27.81, P < 0.001), and an analysis accuracy of 72.9%. The hematological indicators of RBC, HCT, HGB, PLT, PCT, RDW-CV and RDW-SD in blood donors who had infected with mild COVID-19 showed dynamic changes. The discriminant equation for whether they are infected recently with COVID-19 has a high accuracy rate.

Investigation of serum level relationship of pro-inflammatory and anti-inflammatory cytokines with vitamin D among healthy Ghanaian population

BackgroundThe interplay between vitamin D status and inflammatory cytokines in a supposedly sufficient sunshine environment has not well been evaluated. The study sought to determine their association.MethodsThis cross-sectional study involved 500 healthy adult blood donors from some selected hospitals in Ghana enrolled from June to November 2016. Venous blood samples were obtained from participants, 25(OH)D, TNF-alpha, IFN-gamma, and IL 10 were measured using enzyme linked immunosorbent assay (ELISA) technique. Serum levels of 25(OH)D < 20ng/ml were classified as being deficient or low.ResultsThe average age of the participants was 27.97 years. No statistically significant association was established between 25(OH) D status, mean age (p = 0.1693), and gender (p = 0.5461) of study participants. Similarly, the median 25(OH) D (p = 0.8392), IL-10 (p = 0.5355), TNF-alpha (p = 0.9740), and IFN-gamma (p = 0.6908) were not significantly different across gender. There was a significantly increased levels of TNF-alpha (p < 0.0001) and IFN-gamma (p < 0.0001) among participants with 25(OH) D deficiency compared to those without deficiency. Concurrently, participants with 25(OH)D deficiency had a significantly reduced levels of IL-10 (p < 0.0001) compared to those without 25 (OH) D deficiency. The most accurate biochemical markers for identifying 25 (OH) D deficiency were IFN-gamma (AUC = 0.879; p < 0.0001) followed by TNF-gamma (AUC = 0.849; p < 0.0001) and IL-10 (AUC = 0.707; p < 0.0001).ConclusionThere was a significant association between vitamin D levels and pro-inflammatory cytokines (TNF-alpha, IFN-gamma) and anti-inflammatory cytokine (IL 10) among healthy Ghanaian populace.

Abstract B046: Exploring the potential of commensal polyomavirus as a promising approach for breast cancer treatment

Abstract Cancer is a leading cause of mortality worldwide, accounting for nearly one in six deaths. Our understanding of the immune system role in cancer control has increased dramatically in recent decades, facilitating the recent development of effective cancer immunotherapies, which have significantly improved the survival of cancer patients. However, current immunotherapies can induce overactive immune responses with severe even fatal outcomes. Moreover, immunotherapy may not work in every scenario, especially in ‘cold’ tumors that lack immune cell infiltration. Thus, more effective immunotherapies with fewer side effects are under active investigation. Viruses are one of the most abundant biological entities in the world; about 12% to 20% of human cancers are associated with viral infections. Viral antigens can increase tumor immunogenicity, triggering T cell immunity against tumor cells. Polyomaviruses are small, nonenveloped double-stranded DNA viruses that are widespread. In immunocompetent hosts, polyomaviruses remain at a low persistent level in the host after the primary infection, which appears to cause little or no symptoms. Previous studies have shown high polyomavirus seroprevalence and the frequent presence of polyomavirus-specific T cells in healthy adult blood donors. In the elderly population, Merkel cell polyomavirus (MCPyV) infection is linked to Merkel cell carcinoma (MCC), a rare, aggressive skin cancer associated with immunosuppression. MCPyV integration into the genome is the primary oncogenic event in ~80% of MCC cases, and the remaining virus-negative MCC cases are associated with ultraviolet (UV) radiation. MCPyV-induced MCCs are associated with more intratumor immune cells and better responses to cancer therapy. Moreover, BK and JC polyomavirus positive lymphoma patients showed a trend toward significantly better overall survival. These clinical data suggest that polyomavirus in tumors may increase tumor immunogenicity. Thus, polyomavirus presents an intriguing opportunity to develop a novel strategy to enhance cancer immunogenicity. We utilized mouse polyomavirus (MPyV) to colonize typically ‘cold’ breast tumor cell line E0771 breast cancer cells in mice. MPyV infection blocked the growth of tumors in immunocompetent mice and promoted immune cell infiltration when intratumorally delivered to the tumor. The tumor rejection activity of polyomavirus is depend on CD4 and CD8 T cells. Unlike conventional oncolytic viruses which directly lyse the infected cells and trigger a nonspecific inflammatory response, polyomavirus does not lyse the colonized cells, and it induces a relatively low level of inflammation. Instead, polyomavirus stimulates viral antigen expression in tumors that boosts T cell response leading to epitope spreading to tumor-associated antigens. The outcomes of this research will establish the utility of commensal polyomavirus as a novel agent for cancer immunotherapy. Citation Format: YUN XIA. Exploring the potential of commensal polyomavirus as a promising approach for breast cancer treatment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B046.

Blood Donation Practices and Awareness of Blood Types Among Adults in the United Arab Emirates: A Cross-Sectional Community-Based Study

Background Blood donation serves as a crucial component of healthcare systems worldwide, ensuring the availability of blood for life-saving therapies and medical procedures. To date, no studies have assessed the knowledge of blood donors regarding their own blood type, overall awareness of blood types, and blood donation practices within the United Arab Emirates (UAE) population. Aim The present study&amp;apos;s primary objective is to assess knowledge regarding blood types and blood donation practices among adult blood donors in the UAE. The aim is to evaluate the effectiveness of existing initiatives and propose targeted strategies to recruit new donors and retain existing ones, with a specific emphasis on less common or critical blood types like O-negative. Methods This cross-sectional community-based study involved 259 participants selected through convenience sampling. Interviews were conducted at blood donation sites, and blood type data for each participant was collected from the blood bank following their donation. Statistical analysis was conducted using SPSS Statistics version 25 (IBM Corp. Released 2017. IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp.), and p-values of

Effects of heat waves and cold spells on blood parameters: a cohort study of blood donors in Tianjin, China.

With the increasing occurrence of extreme temperature events due to climate change, the attention has been predominantly focused on the effects of heat waves and cold spells on morbidity and mortality. However, the influence of these temperature extremes on blood parameters has been overlooked. We conducted a cohort study involving 2,752 adult blood donors in Tianjin, China, between January 18, 2013, and June 25, 2021. The generalized additive mixed model was used to investigate the effects and lagged effects of heat waves and cold spells on six blood parameters of blood donors, including alanine aminotransferase (ALT), white blood cell count (WBC), red blood cell count (RBC), hemoglobin (HB), hematocrit (HCT), and platelet count (PLT). Subgroup analyses were stratified by sex, age, and BMI. Heat waves and cold spells are associated with changes in blood parameters, particularly HB and PLT. Heat waves increased HB and PLT, while cold spells increased HB and decreased PLT. The effect of heat waves is greater than that of cold spells. The largest effect of heat waves on HB and PLT occurred at lag1 with 2.6 g/L (95% CI: 1.76 to 3.45) and lag7 with 9.71 × 10^9/L (95% CI: 6.26 to 13.17), respectively, while the largest effect of cold spells on HB and PLT occurred at lag0 with 1.02 g/L (95% CI: 0.71 to 1.33) and lag2 with -3.85 × 10^9/L (95% CI: -5.00 to -2.70), respectively. In subgroup analysis, the effect of cold spells on ALT was greater in the 40-49 age group. We indicated that heat waves and cold spells can impact hemoglobin and platelet counts in the human body. These findings provide evidence linking heat waves or cold spells to diseases and may reduce health risks caused by extreme temperature events.

Effect of autologous umbilical cord blood transfusion in the development of retinopathy of prematurity: randomized clinical trial - study protocol.

Currently, the treatment of anemia in preterm infants is based on packed red blood cell (RBC) transfusions from adult donors. Oxygen (O2) is mainly transported to the tissues bound to hemoglobin (Hb). In extremely low gestational age neonates (ELGANs), fetal hemoglobin (HbF), which has a higher affinity for O2, represents up to 95% of circulating hemoglobin. During the first month of life, the majority of ELGANs will require an adult-donor RBC transfusion causing HbF levels to rapidly drop. HbA releases 50% more oxygen in peripheral tissues than HbF. Increased release of O2 in the retina is one of the main factors related to the development of retinopathy of prematurity (ROP). Collecting umbilical cord blood and using autologous umbilical cord whole blood (UCB) transfusions would contribute to maintaining physiological HbF concentrations in newborns and avoid oxygen-in-excess derived damage. This is a randomized, double-blinded, multicenter clinical trial. ELGANs ≤28 weeks of gestational age will be randomized 1:1 to receive an autologous umbilical cord blood transfusion (intervention arm) or standard transfusion of packed RBC from an adult donor (control arm) to assess ROP development. Assuming a 50% reduction in ROP incidence, 134 patients (67 per group) will be recruited. When blood transfusion is indicated, the Blook Bank will supply UCB or RCB according to the patient's group. The primary endpoint is the incidence of any ROP. Secondary endpoints are assessessment of treatment safety, results of biomarkers related to ROP and its chronology, and urine oxidative stress markers. In addition, the cellular composition of umbilical cord blood and its relationship with prematurity-related pathologies will be analyzed. All patients will be followed-up to 24 months of corrected age to evaluate their neurodevelopment. ROP is a major cause of irreversible blindness in preterm newborns. Transfusions with adult donor blood can lead to complications, including ROP. UCB transfusions offer advantages by maintaining physiological HbF levels and potentially optimizing postnatal development. Moreover, autologous UCB transfusion could reduce risks associated with heterologous blood products, although volume collection remains challenging. UCB contains growth factors and progenitor cells that may impact ROP.

Effectiveness of first and second boost COVID-19 vaccination in healthy adults during BA.5.2/BF.7 surge in China

ABSTRACT With the development of the SARS-CoV-2 pandemic, there have been doubts about the necessity of vaccine boosters for healthy adults. However, due to the lack of relevant evidence, current research is unable to provide reliable medical advice for COVID-19 boost in healthy adults. We conducted a retrospective observational study to evaluate the effectiveness of different COVID-19 vaccination regimens by investigating the SARS-CoV-2 infection status of healthy donors in Southeast China. From December 2022 to February 2023, 737 healthy adult blood donors were analyzed. Results showed that any COVID-19 vaccine boosts reduced the risk of Omicron BA.5.2/BF.7 infection compared to only receiving prime vaccination (rVE = 16%, 95%CI = 4, 27%). The second boost further enhanced vaccine effectiveness compared to the received first booster (rVE = 39%, 95%CI = 16, 55%). Through retrospective observation of healthy adults during the BA.5.2/BF.7 surge in China, we found that boost vaccinations significantly reduce the risk of SARS-CoV-2 infection and disease. Findings show healthy adults benefit from boost vaccinations, even if not at high-risk for severe COVID-19.

Prevalence of Thyroid Peroxidase and Thyroglobulin Autoantibodies in the Swedish Population.

Autoimmune thyroid disease (AITD) may be detected prior to clinical symptoms through the presence of autoantibodies against thyroid peroxidase (TPOab), thyroglobulin (TGab), or both.The present study aimed to develop a novel radiobinding assay (RBA) for TPOab and to determine the prevalence of TPOab and TGab in the Swedish population.Patient samples from 27 newly diagnosed Graves' disease patients in longitudinal follow-up and 124 AITD autoantibody-positive children in prospective follow-up for increased risk of type 1 diabetes were included to validate the novel RBA for TPO. The results of RBA were compared with those obtained by commercial radioimmunoassay (RIA) and electrochemiluminescence (ECL). Furthermore, 476 serum samples from adult blood donors and 297 from 13-year-old school children were analyzed for the presence of TPOab and TGab.Receiver operating characteristics analysis for the novel TPOab resulted in an area under curve (AUC) value of 0.82 (p<0.0001), a sensitivity of 77.8%, and a specificity of 91.9% in adult blood donors, and an AUC value of 0.70 (p<0.0001), a sensitivity of 53.2% and a specificity of 95.3% in the 13-year-old school children, respectively. TPOab levels in RBA correlated with both ECL (r=0.8950, p<0.0001) and RIA (r=0.9295, p<0.0001). The prevalence of TPOab and TGab was 6.3% and 7.6% in adult blood donors and 2.9 and 3.7% in 13-year-old school children.In conclusion, a novel RBA for the determination of TPOab was developed and validated with current methodologies. This study also reports an increasing prevalence of thyroid autoantibodies from adolescence to adulthood.

Overcoming difficulties in donor selection for pediatric allogeneic transplantation in a resource- limited country

Objective: Centers in resource-limited countries face significant challenges in performing unrelated donor allogeneic stem cell transplantation. We analyze the outcome of concrete actions taken by our program since 2008 to gain access to worldwide transplant donors, select and procure the preferred donor for our patients, and perform the transplant timely. &#x0D; Methods: We focused on three aspects to gain unlimited access to unrelated donors: hiring and training dedicated nurse coordinators, establishing fluid communication and collaboration with donor registries and cord blood banks, and careful planning of the transplant procedure to avoid delays. We describe the evolution of donor choice since 2008 and the time to transplantation between related (matched sibling and haploidentical) and unrelated (adult and cord blood) donors. &#x0D; Results: We transplanted 238 children between 2008 and 2022. Transplant activity increased from 28 procedures in 2008-2010 to 85 in 2020-2022, mainly at the expense of unrelated donors. The proportion of unrelated donors between both periods increased from 14% to 65% as cord blood usage decreased from 65% to 9% (p&lt;0,001). DKMS donor centers provided 60% of the products. The mean time to transplantation was 68 days for related donors (MSD and haploidentical) and 74 days for unrelated donors (MUD, MMUD, UCB). &#x0D; Conclusion: Despite practicing in a limited resource setting, specific actions allowed us to overcome difficulties in search, procurement, and timely transplantation.

Spread of SARS-CoV-2 Infection in Adult Populations in Cameroon: A Repeated Cross-Sectional Study Among Blood Donors in the Cities of Yaoundé and Douala

Over a period of about 9 months, we conducted three serosurveys in the two major cities of Cameroon to determine the prevalence of SARS-COV-2 antibodies and to identify factors associated with seropositivity in each survey. We conducted three independent cross-sectional serosurveys of adult blood donors at the Central Hospital in Yaoundé (CHY), the Jamot Hospital in Yaoundé (JHY) and at the Laquintinie Hospital in Douala (LHD) who consented in writing to participate. Before blood sampling, a short questionnaire was administered to participants to collect their sociodemographic and clinical characteristics. We included a total of 743, 1202, and 1501 participants in the first (January 25–February 15, 2021), second (May 03–28, 2021), and third (November 29–December 31, 2021) surveys, respectively. The adjusted seroprevalence increased from 66.3% (95% CrI 61.1–71.3) in the first survey to 87.2% (95% CrI 84.0–90.0) in the second survey, and 98.4% (95% CrI 96.8–99.7) in the third survey. In the first survey, study site, participant occupation, and comorbid conditions were associated with SARS-CoV-2 seropositivity, whereas only study site remained associated in the second survey. None of the factors studied was significantly associated with seropositivity in the third survey. Together, the data suggest a rapid initial spread of SARS-CoV-2 in the study population, independent of the sociodemographic parameters assessed.

Von Willebrand factor levels in healthy blood donors and their association with blood group: A tertiary care hospital-based study.

von Willebrand disease is a common inherited bleeding disorder caused by the deficiency of von Willebrand factor (vWF).[1] The levels of vWF depend on several factors, including exercise, hormones, and ABO blood type.[2] This study was planned to evaluate plasma vWF levels and factor VIII (fVIII) levels in healthy blood donors and its association with the ABO blood group. The aim of this study was to evaluate plasma vWF levels and fVIII levels in healthy donors and its association with the ABO blood group. This study was done in 2016 healthy adult blood donors. Complete history and relevant examination were done along with ABO and Rh (D) blood group typing, complete blood count, prothrombin time, activated partial thromboplastin time, vWF antigen (Ag) level, fVIII coagulant assay, and other tests for hemostasis. Data were expressed in proportions and mean, median, and standard deviation, respectively. An appropriate test of significance was applied. P < 0.05 was considered statistically significant. vWF level of donors ranged from 24 to 186 IU/dL with a mean of 96.31 IU/dL. Low vWF Ag level (below 50 IU/dl) was found in 2.5% of donors while 0.1% (2/2016) had level <30 IU/dL. O Rh (D)-positive blood group donors had the lowest vWF level (87.85 IU/dL), while ARh (D)-negative donors had the highest vWF level (117.27 IU/dL). fVIII level of the donor population ranged from 22% to 174%, with a mean of 98.82%. About 2.48% of donors had fVIII levels below 50%. There was a statistically significant correlation between fVIII level and vWF level (P < 0.001).

Parathyroid hormone reference intervals in adults using second- and third-generation assays

Parathyroid hormone (PTH) is a routine biochemical analysis, and it varies whether a second- or third-generation assay is used. Information on the levels obtained with different assays and evidence to substantiate local assay-specific reference ranges are important to inform clinical practice. Prior to a shift from the second- to the third-generation PTH assay (Cobas 8000, Roche Diagnostics) in the Department of Clinical Biochemistry, Aalborg University Hospital, Aalborg, Denmark, a total of 59 EDTA-plasma samples were collected for method comparison (Passing–Bablok). Furthermore, 120 EDTA-plasma samples were randomly obtained from adult blood donors and used for the establishment of reference intervals using the third-generation PTH assay (Cobas 8000, Roche Diagnostics) and two second-generation assays (Atellica, Siemens Healthineers; Alinity, Abbott Laboratories). Method comparison (Cobas 8000, Roche Diagnostics) showed lower levels with the third-generation (y) as compared to the second-generation assay (x) depending on the measurement range (PTH < 10 pmol/L: y = 0.8 (95% CI: 0.7; 0.9) x + 0.3 (95% CI: 0.2; 0.5), PTH ≥ 10 pmol/L: y = 0.6 (95% CI: 0.5; 0.6) x + 3.2 (95% CI: 1.1; 5.2)). Method-specific reference intervals (2.5 and 97.5 percentiles) after the exclusion of samples (n = 31) with 25-hydroxy-vitamin D below 50 nmol/L were: 1.8–8.5 pmol/L (second-generation, Atellica, Siemens Healthineers); 2.4–10.9 pmol/L (second-generation, Alinity, Abbott Laboratories), and 1.8–7.0 pmol/L (third-generation, Cobas 8000, Roche Diagnostics). PTH levels with second- and third-generation assays are not interchangeable. Clinicians should be informed when a laboratory assay is changed, and method-specific reference ranges are needed.

Low level of dengue infection and transmission risk in Hong Kong: an integrated analysis of temporal seroprevalence results and corresponding meteorological data

ABSTRACT Hong Kong is an Asia-Pacific City with low incidence but periodic local outbreaks of dengue. A mixed-method assessment of the risk of expansion of dengue endemicity in such setting was conducted. Archived blood samples of healthy adult blood donors were tested for anti-dengue virus IgG at 2 time-points of 2014 and 2018/2019. Data on the monthly notified dengue cases, meteorological and vector (ovitrap index) variables were collected. The dengue virus (DENV) IgG seroprevalence of healthy adults in 2014 was 2.2% (95%C.I. = 1.8–2.8%, n = 3827) whereas that in 2018/2019 was 1.7% (95%C.I. = 1.2–2.3%, n = 2320). Serotyping on 42 sera in 2018/2019 showed that 22 (52.4%) were DENV-2. In 2002–2019, importation accounted for 95.3% of all reported cases. By wavelet analysis, local cases were in weak or no association with meteorological and vector variables. Without strong association between local cases and meteorological/vector variables, there was no evidence of increasing level of dengue infection in Hong Kong.

A randomized trial of blood donor iron repletion on red cell quality for transfusion and donor cognition and well-being

AbstractAlthough altruistic regular blood donors are vital for the blood supply, many become iron deficient from donation-induced iron loss. The effects of blood donation–induced iron deficiency on red cell transfusion quality or donor cognition are unknown. In this double-blind, randomized trial, adult iron-deficient blood donors (n = 79; ferritin < 15 μg/L and zinc protoporphyrin >60 μMol/mol heme) who met donation qualifications were enrolled. A first standard blood donation was followed by the gold-standard measure for red cell storage quality: a 51-chromium posttransfusion red cell recovery study. Donors were then randomized to intravenous iron repletion (1 g low-molecular-weight iron dextran) or placebo. A second donation ∼5 months later was followed by another recovery study. Primary outcome was the within-subject change in posttransfusion recovery. The primary outcome measure of an ancillary study reported here was the National Institutes of Health Toolbox–derived uncorrected standard Cognition Fluid Composite Score. Overall, 983 donors were screened; 110 were iron-deficient, and of these, 39 were randomized to iron repletion and 40 to placebo. Red cell storage quality was unchanged by iron repletion: mean change in posttransfusion recovery was 1.6% (95% confidence interval −0.5 to 3.8) and −0.4% (−2.0 to 1.2) with and without iron, respectively. Iron repletion did not affect any cognition or well-being measures. These data provide evidence that current criteria for blood donation preserve red cell transfusion quality for the recipient and protect adult donors from measurable effects of blood donation–induced iron deficiency on cognition. This trial was registered at www.clinicaltrials.gov as NCT02889133 and NCT02990559.

The Prevalence of Asymptomatic Infections with Tick-Borne Encephalitis Virus and Attitude towards Tick-Borne Encephalitis Vaccine in the Endemic Area of Northeastern Poland.

In Poland, tick-borne encephalitis (TBE) vaccination rate is low despite high incidence of severe infections with TBE virus (TBEV). However, infection with TBEV can be asymptomatic or mild, which makes the total number of cases difficult to assess. We aimed at assessing asymptomatic TBEV infections and describing attitudes towards the TBE vaccine. We studied 298 healthy adult blood donors and 180 children from the TBE endemic area of northeastern Poland for the presence of anti-TBEV IgG antibodies. We also surveyed a separate cohort of 444 adults. Thirty-eight blood donors (13%) and 38 survey respondents (9%) reported a history of a prior anti-TBEV vaccination. Forty respondents (9%) reported vaccinating their child in the past. Fourteen unvaccinated blood donors (5%) and four children (2%) were seropositive for specific anti-TBEV antibodies, suggesting a history of an undiagnosed TBEV infection. In the surveyed cohort, 130 (32%) expressed their intention to be vaccinated and 144 (36%) expressed their intention to vaccinate their child. This intention was significantly higher in respondents with a recent tick-bite, a diagnosis of tick-borne disease in a close relative, and in males. Our study shows that asymptomatic TBEV infections are common. The acceptance of TBE vaccine is low, but might be increased by communicating risks associated with tick bites.

Hematological Reference Values According to Geographical Region in Jujuy, Argentina.

Armella, Flavia Noelia, and Sandra Stella Lazarte. Hematological reference values according to geographical region in Jujuy, Argentina. High Alt Med Biol. 23:232-239, 2022. Background: Hematological values vary with altitude above sea level. The purpose of this work was to determine the ranges of hematological reference, and the prevalence of anemia and erythrocytosis in adult blood donors from Jujuy, discriminated according to the geographical region, who assisted at the Centro Regional de Hemoterapia from 2016 to 2018. Materials and Methods: A cross-sectional retrospective study was carried out. Men and women donors belonging to the regions of Valles, Yungas, Quebrada, and Puna were analyzed. The percentiles 2.5 and 97.5 were obtained for the hemoglobin (Hb), hematocrit (Ht), red blood cell count (RBCC), and hematimetric indices, according to sex and region. Results: A total of 4,707 men and 3,326 women, ranging from 18 to 65 years of age, who met with the expected clinical criteria in donors, were studied. The anemia prevalence was 2.5% (95% confidence interval [CI] = 2.2%-2.8%), while the erythrocytosis was 4.9% (95% CI = 4.4%-5.4%). The RBCC, Hb, and Ht increased with altitude above sea level. Conclusions: The Hb and Ht were similar to those observed in the Andean populations living at similar altitudes. The anemia prevalence was lower than the global prevalence reported by the World Health Organization, while that of erythrocytosis increased with the altitude above the sea level. The evidence indicates the necessity for laboratories to obtain reference values for their target population. Registro Nacional de Investigaciones (Renis, Ministerio de Salud de Argentina) IS002323.

Persistence of Naturally Acquired and Functional SARS-CoV-2 Antibodies in Blood Donors One Year after Infection.

The developmental course of antibodies produced after a SARS-CoV-2 infection has been insufficiently investigated so far. Therefore, the aim of this study was to investigate the dynamics of SARS-CoV-2 antibody levels against the viral nucleocapsid- and spike-protein among Austrian blood donors as a representative group of a supposedly healthy population within the first year after a SARS-CoV-2 infection. The impact of age, sex, vaccination status, AB0-blood group and awareness about the infection was evaluated. Our study shows that the level of anti-N antibodies is declining, while anti-S antibody levels remain stable. Antibodies detected were functional in vitro. Age, sex and blood group do not influence antibody dynamics. However, blood group AB shows significantly lower antibody levels and in vitro functionality compared to other blood groups. Our data reveal that one out of five individuals was not aware of a previous SARS-CoV-2 infection and that the disease course neither affects the level of antibody production nor the in vitro functionality. We also found that 14% of participants show persisting COVID-19-related symptoms for up to nine months. Our results provide valuable insights into the dynamics of the immune response after a SARS-CoV-2 infection in a representative cohort of adult blood donors in Central Europe.