Resumo em Inglês:

ABSTRACT Introduction and hypothesis: Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells for allogeneic hematopoietic stem cell transplantation in the absence of a compatible donor. The UCB transplantation has a lower incidence of chronic graft versus host disease (GvHD), but is associated with slower engraftment and slower immune reconstitution, compared to other sources. Dendritic cells (DCs) and Natural Killer cells (NKs) play a central role in the development of GvHD and the graft versus leukemia (GvL) effect, as well as in the control of infectious complications. Method: We quantified by multiparametric flow cytometry monocytes, lymphocytes, NK cells, and DCs, including their subsets, in UCB samples from 54 healthy newborns and peripheral blood (PB) from 25 healthy adult volunteers. Results: In the UCB samples, there were higher counts of NK cells 56bright16– (median 0.024 × 109/L), compared to the PB samples (0.012 × 109/L, p < 0.0001), NK 56dim16bright (median 0.446 × 109/L vs. 0.259 × 109/L for PB samples, p = 0.001) and plasmacytoid dendritic cells (pDCs, median 0.008 × 109/L for UCB samples vs. 0.006 × 109/L for PB samples, p = 0.03). Moreover, non-classic monocyte counts were lower in UCB than in PB (median 0.024 × 109/L vs. 0.051 × 109/L, respectively, p < 0.0001). Conclusion: In conclusion, there were higher counts of NK cells and pDCs and lower counts of non-classic monocytes in UCB than in PB from healthy individuals. These findings might explain the lower incidence and severity of chronic GvHD, although maintaining the GvL effect, in UCB transplant recipients, compared to other stem cell sources.

Resumo em Inglês:

ABSTRACT Introduction: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. Method: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). Main results: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. Conclusion: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.

Resumo em Inglês:

ABSTRACT Introduction: Pre-apheresis peripheral blood CD34+ cell count (PBCD34+) is the most important predictor of good cell mobilization before hematopoietic stem cell transplantation, albeit flow cytometry is not always immediately available. Identification of surrogate markers can be useful. The CD34+ cells proliferate after mobilization, resulting in elevated lactate dehydrogenase (LDH) activity and correlating with the PBCD34+ count. Objective: To determine the LDH cut-off value at which adequate CD34+ cell mobilization is achieved and its diagnostic yield. Materials and methods: A total of 103 patients who received an autologous stem cell transplantation (ASCT) between January 2015 and January 2020 were included. Demographic and laboratory characteristics were obtained, including complete blood count, pre-apheresis PBCD34+ and LDH levels. Receiver operating characteristic (ROC) curves were performed to identify the optimal serum LDH activity cut-off points for ≥ 2 and ≥ 4 × 106 cells/kg post-mobilization CD34+ count and their diagnostic yield. Results: A post-mobilization serum LDH cut-off value of 462 U/L yielded a sensitivity (Se) = 86.8% (positive predictive value [PPV] = 72.7%), a pre- and post-mobilization serum LDH difference cut-off value of 387 U/L, an Se = 45.7% (PPV = 97%) and an LDH ratio of 2.46, with an Se = 47.1% (PPV = 97%) for an optimal mobilization count (CD34+ ≥ 4 × 106). Conclusion: The LDH measurement represents a fast and affordable way to predict PBCD34+ mobilization in cases where flow cytometry is not immediately available. According to the LDH diagnostic yield, it could be used as a surrogate marker in transplant centers, supporting the CD34+ count, which remains the gold standard.

Resumo em Inglês:

ABSTRACT Introduction: Knowledge, Attitude and Practices (KAP) surveys prove beneficial to the transfusion services by providing an insight into the donors and, thus, aiding in mobilizing and retaining voluntary blood donors. We aim to study the knowledge, attitude and practices of donors towards blood donation in a pandemic setting. Methods: A cross-sectional observational study to assess the knowledge, attitude and practices of blood donors was conducted between June to and October 2020. Non-parametric tests (Mann – Whitney U and Kruskal - Wallis) were performed to evaluate the relation of knowledge, attitude and practices overall scores with age group, gender and history of blood donations (first us. repeat). The Chi-Square test/Fisher's Exact test was used to evaluate the differences in the distribution of Knowledge, Attitude and Practices items within the groups. Results: A total of 403 of 2,748 individuals who came for whole blood donation participated in the study. The mean age of the study population was 31.1years (SD ± 8.4 range: 18 - 58), with 75% of the donors donating for the first time. The fear of acquiring COVID-19 infection was perceived as a major reason for the eligible population not to donate. The overall knowledge, attitude and practice score among the donors was satisfactory, being 76.14%, with a significant association with age. The overall positive attitude and practices scores of blood donors were 85.48% and 78.04%, respectively. Conclusion: The KAP scores were satisfactory among the donors. Timely communication of the precautionary measures at blood centers to contain the spread of the COVID-19 infection and effective counseling would help in motivating and retaining blood donors.

Resumo em Inglês:

ABSTRACT Introduction: The para-Bombay phenotype, or H-deficient secretor, results from different mutations of the FUT1, with or without the FUT2 mutation. Consequently, there is an absent or weak expression of the H antigen on red blood cells (RBCs). Routine ABO blood grouping for two siblings with blood group O showed discrepant results with their parental blood group AB. Fragments encompassing the entire coding region of the FUT1 and FUT2 genes were investigated. Methods: Blood and saliva specimens were collected to verify the correct ABO grouping by cell grouping, serum grouping and the hemagglutination inhibition (HI) test, respectively. The FUT1 and FUT2 genomes were identified using the whole-exome sequencing (WES) in two children's DNA blood specimens and may have caused, or been relative to, their blood group. Genetic variations of the FUT1 and FUT2 genes have been investigated in the other family members using the Sanger sequencing. Results: The serologic reaction results of the proband revealed that A, B and H antigens were absent on RBCs, and that the serum contained anti-H. However, ABH and AH antigens were present in the saliva PB1 and PB2, respectively. The probands PB1 and PB2 were assigned as AB and A blood groups, respectively. Blood genotyping confirmed that heterozygous mutations of the FUT1 gene, c.551_552delAG, were identified. Three family members, PB3, PB, and PB8, also showed normal ABO blood groups, but their genotypes were also the FUT1 mutation c.551_552delAG. Conclusions: The FUT1 mutation c.551_552delAG may result in the reduced or absent H antigen production on RBCs, which characterizes the para-Bombay phenotypes. Blood genotyping is essential if these individuals need a blood transfusion or are planning to donate blood.

Resumo em Inglês:

ABSTRACT Introduction: Approximately 55.52% of the Indian population had been fully vaccinated by Jan. 2022, since its first roll out on January 16, 2021. A few concerns were raised concerning the Covishield vaccination related to thrombotic thrombocytopenia. Apheresis-derived platelet concentrates are frequently required in a plethora of clinical situations and post-vaccination decrement of platelet counts might lead to increased deferral of the plateletpheresis donors. Objectives. The aim of the study was to discover the effect of the Covishield vaccination on deferral rates of plateletpheresis donors. Methods: Blood samples were collected from the potential platelet donors for the completion of the standard questionnaire for the complete blood count. The data collected were tabulated in the MS Excel spreadsheet and the biostatistical analysis was performed with the SPSS v23. A p-value of < 0.05 was taken as significant. We compared this data with age-and sex-matched controls. Results: The mean age of cases and controls was 29.69 ± 8.57 and 30.15 ± 7.11, respectively. There was a significant difference in platelet counts of cases (188496.35 ± 72065.66/cumm) and controls (269524.50 ± 53981.60/cumm). Furthermore, donors who received one dose had higher platelet counts of 248676.47 ± 80075.24/cumm than those who received both doses of vaccine (179970.83 ± 66773.73/cumm). The difference in deferral rates between the two groups was remarkable (34.7% vs. 0.9%, with the p-value < 0.001). Conclusion: Vaccination certainly increased the deferral rates of plateletpheresis donors due to low platelet counts. Average platelet counts were low in fully vaccinated individuals, however, the platelets returned to normal counts as the post-vaccination days progressed.

Resumo em Inglês:

ABSTRACT Introduction: Immune dysfunction and thrombocytopenia are common features in liver cirrhosis. Platelet transfusion is the most widely used therapeutic approach for thrombocytopenia when indicated. The transfused platelets are prone to lesions during their storage that empower their interaction with the recipient leucocyte. These interactions modulate the host immune response. The impact of platelet transfusion on the immune system in cirrhotic patients is little understood. Therefore, this study aims to investigate the impact of platelet transfusion on neutrophil function in cirrhotic patients. Methods: This prospective cohort study was implemented on 30 cirrhotic patients receiving platelet transfusion and 30 healthy individuals as a control group. EDTA blood samples were collected from cirrhotic patients before and after an elective platelet transfusion. Flowcytometric analysis of neutrophil functions (CD11b expression and PCN formation) was performed. Results: There was a significant increase in expression of CD11b on neutrophils and Frequency of platelet-complexed neutrophils (PCN) in patients with cirrhosis compared with controls. Platelet transfusion increased level of CD11b and the frequency of PCN even more. There was a significant positive correlation between change in PCN Frequency pefore and after transfusion and the change in expression of CDllb among cirrhotic patients. Conclusions: Elective platelet transfusion appears to increase level of PCN in cirrhotic patients, moreover, exacerbate the expression of activation marker CDllb on both neutrophils and PCN. More research and studies are needed to corroborate our preliminary findings.

Resumo em Inglês:

ABSTRACT Introduction: Patients with β-thalassemia major (β-TM) are at risk of developing abnormal lipid profiles. Lipid abnormalities, in turn, have a potential role in the pathogenesis of some clinical aspects of thalassemia Objectives: To evaluate lipid levels and atherogenic indices in β-TM patients compared to healthy children and for any association between lipid levels, lipid peroxidation and inflammatory biomarkers Methods: This case-control study was carried out on 79 patients with β-TM, aged 6 to 16 years, registered at the Basrah Center for Hereditary Blood Diseases and 85 age- and sex-matched apparently healthy children and adolescents. Complete blood count, serum lipids and ferritin, liver function tests, C-reactive protein (CRP), high-sensitivity CRP (hs-CRP) and serum malondialdehyde (MDA) were evaluated Results: Patients with β-TM had significantly lower hemoglobin (Hb), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and non-high-density lipoprotein (non-HDL) and significantly higher very low-density lipoprotein (VLDL), triglycerides (TGs), LDL/HDL ratio, MDA, hs-CRP, total serum bilirubin (TSB), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) than the control group (p < 0.05). A bivariate analysis revealed that TC has a significant positive association with Hb. The TG has a significant negative association with Hb and a positive association with serum ferritin. Furthermore, MDA, TG, TSB, ALT and AST were significantly positively correlated with serum ferritin (p < 0.05) Conclusions: Atherogenic dyslipidemia, defined as a high low-density lipoprotein cholesterol (LDL-C/high-density lipoprotein cholesterol (HDL-C) ratio and high TG level, is common among pediatric β-TM patients, it is associated with iron overload and places patients at an increased cardiovascular risk.

Resumo em Inglês:

ABSTRACT Introduction: The treatment of acute lymphoblastic leukemia (ALL) has evolved in recent decades, reaching an overall survival rate close to 90%. Currently, approximately 4% of patients with ALL die from secondary complications of chemotherapy. Among these complications, the most frequent is febrile neutropenia (FN). The treatment of acute myeloid leukemias (AMLs) is even more aggressive, being consequently related to a considerable amount of treatment-related toxicity with a high risk of severe infection and death. Method: In order to reduce the infection-related risks in these groups of patients, systemic antibacterial prophylaxis has emerged as a possible approach. Results: Antibiotic prophylaxis during neutropenia periods in those undergoing chemotherapy have .already been proven in adults with acute leukemias (ALs). Among the possible available therapeutic options for bacterial prophylaxis in children with cancer, fluoroquinolones emerged with the most amount of evidence. Within this class, levofloxacin became the best choice. Conclusion: Therefore, the use of levofloxacin seems to be indicated in very specific situations: in children who are known to be neutropenic for a long time, secondary to intensive chemotherapy; in children with AL undergoing chemotherapy to induce remission; or in children undergoing hematopoietic stem cell transplantation (HSCT). This article aims to describe recent evidence focusing on antibiotic prophylaxis in children with ALs.

Resumo em Inglês:

ABSTRACT Objectives: To verify the association between the ABO blood type and the risk of SARS-CoV-2 infection and COVID-19 disease severity. Methods: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), using the 2020 PRISMA Checklist and flow diagram, and articles selected for review were analyzed using the Newcastle-Ottawa Quality Rating Scale. The research question was: "Would the ABO blood group influence the risk of infection and clinical course of patients infected with SARS-CoV-2?", The following databases were used: Embase, PubMed, Virtual Health Library (VHL), Web of Science, Science-Direct and Scopus. The protocol for this review was registered in the Prospective Register of Systematic Reviews (PROSPERO), number CRD42021245945. Results: We found 798 articles across PubMed, Embase, Scopus, Web of Science, Science Direct and Virtual Health Library and 54 articles were included in the final analysis. Among 30 studies evaluating the risk of COVID-19 infection, 21 found significant correlations with ABO blood groups, 14 of them revealing an increased risk in blood group A and 15 studies showing a decreased risk in blood group O. Most studies found no significant correlation with disease severity or mortality. Conclusion: The qualitative assessment of available information suggests that blood group A may be a risk factor for COVID-19 infection and that blood group O may have a protective effect. We were unable to determine a clear association between the ABO blood group and mortality. These conclusions are based on highly heterogenous evidence.