A Influencia Do Sistema De Grupo Sanguineo Abo Na Suscetibilidade E Letalidade Da Covid-19

Objetivo: Realizar um estudo descritivo, sintetizando, analisando e discutindo as informacoes mais recentes sobre a influencia do sistema de grupo sanguineo ABO na COVID-19, a partir de uma revisao sobre a biossintese e base molecular do sistema ABO e sua relacao com a suscetibilidade a infeccao pelo SARS-CoV-2 e letalidade da doenca, a partir da sua relacao com trombofilias e eventos cardiovasculares na COVID-19. Metodologia: Foram realizadas pesquisas em bases de dados e bibliotecas cientificas, tais como Pubmed, Scielo, e Nature, utilizando palavras-chave como "COVID-19", "SARS-CoV2", "Coronavirus", "Sistema de Grupo Sanguineo ABO", "Hemostasia", "Trombose", "Fator de von Willebrand", "ADAMTS13" e, ao todo, foram utilizados 53 trabalhos, entre livros e artigos cientificos, dos quais as informacoes utilizadas foram cuidadosamente selecionadas a fim atender ao objetivo proposto. Resultados/Discussao: Alem de sua elevada relevancia para a clinica transfusional, o sistema de grupo sanguineo ABO ja foi associado a suscetibilidade e fisiopatologia de diversas infeccoes e enfermidades. Com a pandemia do novo Coronavirus nao foi diferente. Estudos relacionaram este grupo de antigenos eritrocitarios a suscetibilidade e letalidade da COVID-19, e apontaram uma maior predisposicao a infeccao para o grupo A, bem como um pior prognostico da doenca, ao passo que, o reduzido numero de infectados e obitos no grupo O poderia indicar um efeito protetor nestes individuos. O fenotipo A esta relacionado a uma maior predisposicao a eventos tromboticos devido ao aumento do FVW na circulacao desses individuos, fator que, quando somado ao potencial trombogenico da doenca causada pelo SARS-CoV2, pode ser um agravante no seu prognostico, de modo a possibilitar a evolucao a um quadro mais grave com implicacoes cardiovasculares, que podem levar a sindrome do desconforto respiratorio agudo, alem da ocorrencia de trombose venosa profunda, acidente vascular encefalico isquemico, infarto agudo do miocardio, tromboembolismo pulmonar e trombose placentaria. Conclusao: E observada nao apenas uma maior vulnerabilidade em relacao ao grupo A na infeccao pelo SARS-CoV2, como tambem um maior risco de evolucao para a forma grave da doenca, possivelmente o que se deve a N-Acetilgalactosamina como elemento facilitador na ancoragem do virus as celulas suscetiveis. O efeito contrario e observado para o grupo O, que se encontra em menor proporcao nos numeros de infectados e de obitos pela doenca, sugerindo um efeito protetor nestes individuos, que poderia ser explicado pela presenca de anticorpos anti-A circulantes no soro, principalmente do isotipo IgG, que seriam mais efetivos na neutralizacao do virus contendo antigenos ABO em seu envelope. A predisposicao a eventos vaso-oclusivos a partir do Sistema de Grupo Sanguineo ABO em individuos nao-O, principalmente no grupo A, e um importante fator que, quando somado ao potencial trombogenico da COVID-19, pode ser um agravante significativo na letalidade da doenca causada pelo SARS-CoV2 nesses pacientes, uma vez que, apos infectados, a probabilidade de evolucao a um quadro mais grave com implicacoes tromboembolicas e mais elevada devido a maior concentracao plasmatica de FvW nesses individuos. Copyright © 2022

Correlacao Entre Os Grupos Sanguineos E as Alteracoes Imuno-Hematologicas Na Covid-19

Objetivo: Identificar padroes entre os grupos sanguineos e as alteracoes imuno-hematologicas em pacientes com COVID-19 atendidos no Hospital das Clinicas da Faculdade de Medicina de Botucatu (HCFMB), no periodo marco de 2020 a outubro de 2021. Material e metodos: Avaliou-se 186 pacientes internados com o teste RTq-PCR positivo para COVID-19 e esses foras separados em dois grupos: 105 pacientes nao transfundidos e 81 pacientes transfundidos. Selecionou-se os resultados dos exames de tipagem ABO e RhD, pesquisa de anticorpos irregulares (PAI), marcadores de hemolise (hematocrito, hemoglobina e bilirrubina), desidrogenase lactica (DHL) e hemocomponentes transfundidos. Resultados: No que tange a tipagem sanguinea ABO e RhD, em pacientes nao transfundidos, foi observado que 39 eram do tipo A (37%), 19 do tipo B (18%), 4 do tipo AB (4%) e 43 do tipo O (41%). Desses, 93 pacientes eram RhD positivos (89%) e 12 eram RhD negativos (11%). Ja para os pacientes transfundidos, 35 pacientes eram do tipo A (43%), 13 do tipo B (16%), 4 do tipo AB (5%) e 29 do tipo O (36%). Em relacao ao fator RhD, 69 pacientes eram positivos (85%) e 12 negativos (15%). Os resultados obtidos foram comparados com a frequencia da tipagem sanguinea presente na populacao brasileira, sendo observado que houve menos pacientes do tipo O infectados pelo novo Coronavirus (p = 0,0071), como tambem para transfusoes sanguineas realizadas (p = 0,0235). Os pacientes transfundidos apresentaram maior frequencia estatisticamente significativa (p < 0,0001) de anticorpos irregulares quando comparados com os pacientes nao transfundidos, com destaque para presenca de crioaglutinina. Observou-se diferenca estatistica significativa de alteracoes dos valores dos marcadores de hemolise nos pacientes transfundidos, em que as medias dos valores encontrados foram de 28,93% para hematocrito, 9,41g/dL para hemoglobina e 1,4mg/dL para bilirrubina, indicando a existencia de anemia e destruicao celular. Discussao: Em relacao a tipagem sanguinea ABO, observou-se que houve mais pacientes do tipo A transfundidos quando comparados com as outras tipagens, enquanto mais pacientes com tipagem O nao necessitaram de transfusoes sanguineas. Para ambos houve o predominio do fator Rh positivo. Segundo a literatura, o grupo sanguineo A foi associado a um risco aumentado de infeccao em relacao ao grupo O, devido a presenca de anticorpos naturais anti-A, os quais sao capazes de inibir de forma especifica a proteina Spike do virus de se ligar efetivamente aos receptores da ECA2. Na identificacao de anticorpos irregulares, as crioaglutininas estiveram presentes na maioria dos pacientes com PAI positivo e sua presenca prejudicou as analises laboratoriais, atrasando a liberacao dos resultados dos testes imuno-hematologicos. Conclusao: Portanto, identificou-se correlacao entre os resultados alterados dos marcadores de hemolise com o desenvolvimento da forma mais grave da COVID-19 e a necessidade de transfusao de hemocomponentes, sendo o concentrado de hemacias (CH) o mais utilizado para tratar a anemia estabelecida nesses pacientes. Copyright © 2022

BLOOD GROUPS AND ACUTE RESPIRATORY VIRAL INFECTION COVID-19

Introduction. Polysaccharides, glycoproteins and glycolipids, which determine the group-specific properties of human blood, are both structural elements of the whole organism and determine its predisposition to certain somatic and infectious diseases. Thus, the blood group of an individual can be used among other markers and/or prognostic factors of the occurrence and course of certain groups of diseases. Aim - analysis of literature sources characterizing the relationship of blood groups with COVID-19 ARVI, as well as the mechanisms underlying this relationship. Main findings. The Oaß(I) phenotype ensures an individual's resistance to infection with the SARS-CoV-2 virus and allows for a relatively mild course of the disease. The Aß(II) phenotype is a risk factor for the development of COVID-19 ARVI, in its severe course, the occurrence of complications and increased mortality. An additional component of protection in the form of a negative Rh-affiliation of the infected person is not excluded. The protective properties of the Oaß(I) phenotype are associated with the absence of polysaccharide A in an individual and the presence of anti-A antibodies. The increased risk of COVID-19 ARVI among Aß(II) individuals is due to the large polymorphism of polysaccharide A in the environment and the lack of natural immunity to other forms of polysaccharide A in this group.

The spectrum of ABO hemolytic disease of the fetus and newborn in neonates born to Group O mothers

Background: ABO hemolytic disease of the fetus and newborn (ABOHFDN) is a frequent event, and usually a problem of the neonate rather than the fetus, however, it is difficult to predict the disease severity. Thus, there is a need to increase awareness towards ABOHFDN for optimizing care in terms of early diagnosis and adequate monitoring. Aims: To determine the frequency of ABO-incompatibility in neonates born to group O mothers and to assess the severity of ABO-HDFN in neonates and determine the neonatal outcomes. Methods: This prospective observational study was carried out from February 2020 to May 2021 after obtaining a written informed consent from the mothers. A total of 260 neonates born to blood group O mothers were recruited. The maternal red cell antibody screen (ABS) using a 3-cell panel (Diacell, Bio-Rad, Switzerland) and the neonatal direct antiglobulin test (DAT) were done by column agglutination technique (CAT). For DAT positive samples, the IgG subclass of anti-A/anti-B was determined using DAT IgG1/IgG3 screening cards (Bio-Rad, Switzerland) and a heat elution at 56°C was also performed. The maternal anti-A/anti-B IgG titers was determined by tube technique after treating the serum sample with 0.01 M di-thiothreitol (DTT). The neonatal total serum bilirubin (TSB) and other relevant parameters were also recorded. The requirement for treatment in terms of phototherapy and/or exchange transfusion (ET) and the neonatal outcome were also recorded. Due to travel restrictions during the ongoing COVID-19 pandemic, the follow-up was performed telephonically with parents 6-8 weeks after discharge. Results: Of the 260 group O mothers, none had positive ABS. Of the 260 neonates born to them as an outcome of singleton pregnancies, 84 with blood group O were excluded from the study. The overall frequency of ABO-incompatibility between mother and neonates was 67.69% (176/260). Out of 176 neonates, 77 (43.8%) were group A and 99 (56.2%) were group B, and 15 (8.5%) of them had a positive DAT. Overall, 26.7% (47/176) neonates received phototherapy and 172 (97.7%) neonates survived. The mean (±SD) duration of phototherapy (hours) was 34.17 (±25.67) hours and it ranged from 12- 120 h. Only 1 neonate required ET. None of the neonates required readmission. The median maternal IgG anti-A titre was 16 (8-64) (range: 2-512), while the IgG anti-B titre was 32 (32-64) (range: 4- 512) (p = <0.001). The maximal TSB in neonates had a significant positive association with neonatal birth weight (p = 0.045), maturity at birth (p = 0.037), positive DAT (p = 0.006) and requirement of phototherapy (p = <0.001). Neonatal DAT positivity was significantly associated with maternal IgG titers (p = <0.001), neonatal PCV (p = 0.017), maximal TSB (p = 0.006), requirement (p = <0.001) and duration of phototherapy (p = 0.024). At a cut-off of maternal IgG titre ≥64, it predicted the requirement of phototherapy with a sensitivity of 72.3% and a specificity of 72%. The relative risk (95% CI) of a DAT positive neonate requiring phototherapy was calculated to be 4.55 (3.12-6.33). Summary/Conclusions: The frequency of ABO-incompatibility in neonates born to group O mothers was 67.69% (176/260). The maternal IgG titre of anti-A/anti-B of 64 or more could be a good predictor for identifying the neonates at-risk for developing hyperbilirubinemia requiring further management and combining it with neonatal DAT further enhances the sensitivity to identify such at-risk neonates.

Transfusion errors in the COVID-19 ward resulting in changes in standard operating procedures (SOP)

Background: The pandemic of COVID-19 has led to alterations in SOP across the transfusion process, including administration of blood in COVID-19 wards. COVID-19 patients who present with symptomatic anaemia and have multiple risk factors will need blood transfusions. ABO-incompatible blood transfusions leading to acute haemolytic transfusion reaction is a rare but potentially fatal complication. The National Haemovigilance Coordinating Centre of the National Blood Centre, Malaysia reported the national incidence of incorrect blood components transfused (IBCT) in relation to total blood products transfused in 2019 to be 75 per 10,000 units. Five IBCTs reported were related to administration errors. Aims: We reported two IBCTs involving two patients who required blood transfusions in a COVID-19 ward. Patient 1 was a 74 year old man who complained of chest pain, with a haemoglobin (Hb) of 5.7 g/ dl. Patient 2 was a 50 year old woman with a Hb of 6.4 g/dl. When the two units of blood arrived on the ward, one doctor completed the pre-administration checklist in the 'clean' zone, which Nurse 1 then counter-checked. Nurse 1 put the two blood bags into separate transparent plastic bags and labelled them with the wrong patient's identity sticker. She then handed both blood bags to Nurse 2 in the 'dirty' zone, without the patients' blood compatibility labels, blood request forms and bedside checklist forms. Positive patient identification was not done by Nurse 2 and the transfusions commenced. Patient 1 complained of chills around 10 min into the transfusion. The error was only realized 35 min into the transfusion when the symptoms persisted and the temperature taken was 38°C. Patient 2, who was given a unit of group O blood that belonged to Patient 1, did not report any adverse reactions. Our aim is to identify the root causes of these IBCTs and to execute the necessary changes in pre-transfusion SOP to minimize future recurrences. Methods: Samples from both patients were investigated for transfusion reactions. Rechecking of blood groups was done manually with the test tube method. Direct and indirect anti human globulin tests (DAT/IAT) and recheck of cross-matching were performed with the column agglutination technology (CAT) method at 37/AHG phase. Urine samples were tested using urine dipsticks. Isohaemagglutinin (anti-A/B titre) was performed using the CAT method at 37/AHG phase. Plasma Hb was measured with a photometer and a microcuvette. Results: Both patient 1's post-transfusion samples (immediate and post-24 h) were O-RhD positive. Blood group of the donor's bag was B-RhD positive. DAT for both samples was positive with IgG(3+) and C3D (1+). IAT for both samples was negative. Recheck of crossmatching with both samples was incompatible (4+). Urine tests were negative for haemoglobin. A low anti-B titre of 1:16 was detected. Plasma Hb was measured twice at a low level below the reference range. Patient 2's workup was unremarkable. Summary/Conclusions: Two IBCTs occurred in the COVID-19 ward, with one major ABO-mismatched IBCT due to human errors and deviation from standard SOP. Pre-transfusion SOP was still unclear in the COVID-19 ward setting prior to these incidences. All medical personnel in the COVID-19 ward underwent retraining on safe transfusion practices. One COVID-19 patient's blood compatibility label, blood request form, bedside checklist form and blood bag should be brought into 'dirty' zone to be checked by two medical personnel at one time.

Reduced levels of ABO anti-A and anti-B of IGM, IGG and IGA isotypes in the serum but not the saliva of individuals recovered from COVID-19

Background: Recent studies reported that individuals with ABO blood type O are underrepresented among patients infected with severe acute respiratory syndrome coronavirus SARS-CoV-2 compared with controls. Our preceding study results indicated a lower proportion of individuals with blood type O accompanied by a higher incidence of blood type AB in patients hospitalized with COVID-19 than in healthy blood donors. Thus, we hypothesized that the variable susceptibility to infection with SARS-CoV-2 might be related to interference caused by circulating ABO antibodies and further may be influenced by the antibody titers which vary widely between individuals. Aims: Therefore, we aimed to investigate ABO antibody levels, including IgM, IgG and IgA subclasses, in the serum and saliva of Caucasians (n = 187), who recovered from mild COVID-19 and to compare them with those of individuals who had never been infected with the virus. Further, a possible association between ABO antibodies and virusspecific total antibody concentrations in the COVID-19 convalescents as well as a potential relationship between the total IgA secreted in saliva and anti-A/anti-B specific IgA in saliva specimens were addressed. Methods: The convalescent study participants were recruited between June 2020 and February 2021. Individuals who had been hospitalized with COVID-19 or who were pregnant were excluded from the study. Two samples were collected within 2 months after the diagnosis (median days: 44) and approximately 2 months later (median days: 66 days). Isotype specific anti-A and anti-B were determined by flow cytometry on a FACS Canto II. The results were compared with the levels in samples from blood and saliva donors. The antibodies specific to SARS-CoV-2 as well as total IgA in saliva were tested by ELISA. Results: COVID-19 convalescents had significantly lower levels of anti-A and anti-B IgM, IgG and IgA in their serum than control subjects (p < 0.001). ABO antibody levels tested in saliva of participants who previously suffered from COVID-19 did not differ significantly from antibody levels tested in saliva controls (p ≥ 0.338). ABO antibody levels remained stable over the period considered. No significant association between the level of ABO antibodies and SARS-CoV-2-specific antibodies was observed (-0.44 < rho < 0.42, p > 0.053). Total IgA in saliva was lower in convalescents than in controls (p = 0.038). Summary/Conclusions: We observed consistently lower serum concentrations of anti-A and anti-B in COVID-19 convalescents than in healthy controls, suggesting ABO antibodies to conferring a degree of protection against SARS-CoV-2 infection. There may be an increased susceptibility to SARS-CoV-2 infection due to individual preexisting low ABO antibody levels. However, the mechanism underlying our observation of significantly reduced ABO antibodies in the serum, but not in the saliva of affected individuals remains unresolved. Further studies to better understand the molecular mechanism underlying our observation are needed.