Increasing rate of anti-SARS-CoV-2 antibodies between the first and second waves of COVID-19 in Sao Paulo, Brazil: A cross-sectional blood donors-based study

ABSTRACT Background: SARS-CoV-2 infections rapidly spread along with Brazilian territory with heterogeneous transmission and mortality rates, mostly depending on region and period. Investigation of SARS-CoV-2 antibodies is an important tool to understand virus circulation. Given that blood donors are a representative casuistic of a healthy population, the authors evaluated the seroprevalence of IgG and IgM COVID-19 antibodies in 2,806 blood donors from a blood bank located in São Paulo, Brazil. Methods: Aiming to evaluate viral behavior over time, the authors selected samples from blood donors who donated in June and October 2020, and February 2021. To determine whether socio-demographic features affected the seroprevalence, the authors analyzed samples from three different regions from São Paulo (capital, metropolitan and countryside regions) and evaluated predictors as gender, age, educational level, race, and use of public transportation. Results: As expected, the authors observed that seroprevalence increased over time. Seroprevalence was greater in São Paulo city compared to metropolitan and countryside regions, being smallest in the countryside. Characteristics associated with a lower percentage of antibodies were age above 50 years, higher educational level, self-declared Caucasian, and use of individual transportation. Conclusion: In conclusion, blood donors' samples proved to accurately reflect virus circulation in the healthy population.

Optimization of red blood cell unit storage during SARS-COV-2 Pandemic: adopting new strategies to ensure supply in a decentralized blood bank in Brazil

ABSTRACT Introduction: As coronavirus disease-2019 (COVID-19) spread worldwide and social restrictions were intensified, difficulties in blood supply were expected to result in a shortage of blood donors, logistic issues and a change in blood consumption. Consequences could be detrimental to the meeting of the blood supply demand, especially in a decentralized blood bank in the State of São Paulo responsible for providing blood to more than 100 hospitals, mostly of the public health system. Aiming to minimize negative effects and focusing on maintenance of the blood supply, a different approach was discussed and adopted. Materials and methods: Briefly, strategies were related to monitoring and promoting measures to achieve a positive RBC unit balance. Thus, the number of donors, transfusions, RBC unit inventory, RBC unit loss and RBC units within up to 5 days from the expiration date were evaluated. Results: Several strategies were adopted to ensure sufficient availability of RBC units: blood donation was improved with social media and extra blood collections, a restrictive transfusion protocol was implemented, a new logistic process to use RBC units closer to the expiration date was established and non-isogroup transfusions were avoided. Conclusion: Altogether, described strategies were crucial to optimize blood storage during the pandemic. Investing in monitoring and logistics contributed to a positive RBC unit balance and conserving these strategies could be useful.

Optimization of red blood cell unit storage during SARS-COV-2 Pandemic: adopting new strategies to ensure supply in a decentralized blood bank in Brazil.

INTRODUCTION: As coronavirus disease-2019 (COVID-19) spread worldwide and social restrictions were intensified, difficulties in blood supply were expected to result in a shortage of blood donors, logistic issues and a change in blood consumption. Consequences could be detrimental to the meeting of the blood supply demand, especially in a decentralized blood bank in the State of São Paulo responsible for providing blood to more than 100 hospitals, mostly of the public health system. Aiming to minimize negative effects and focusing on maintenance of the blood supply, a different approach was discussed and adopted. MATERIALS AND METHODS: Briefly, strategies were related to monitoring and promoting measures to achieve a positive RBC unit balance. Thus, the number of donors, transfusions, RBC unit inventory, RBC unit loss and RBC units within up to 5 days from the expiration date were evaluated. RESULTS: Several strategies were adopted to ensure sufficient availability of RBC units: blood donation was improved with social media and extra blood collections, a restrictive transfusion protocol was implemented, a new logistic process to use RBC units closer to the expiration date was established and non-isogroup transfusions were avoided. CONCLUSION: Altogether, described strategies were crucial to optimize blood storage during the pandemic. Investing in monitoring and logistics contributed to a positive RBC unit balance and conserving these strategies could be useful.

Serologic strategy in detecting RHD altered alleles in Brazilian blood donors

ABSTRACT Background: We evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors. Methods: We selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spin (IS) with eleven commercially available anti-D reagents in a tube and microplate. The D confirmatory tests for the presence of weak D included the indirect antiglobulin test (IAT) in a tube, gel and solid-phase red blood cell adherence (SPRCA). All DNA samples were extracted from peripheral blood and the D variants were classified using different molecular assays. Results: The RHD variants identified by molecular analysis included weak D types (1, 2, 3, 11 and 38) and partial Ds (DAR1.2, DAR1, DAR3.1, DAU0, DAU2, DAU4, DAU5, DAU6, DMH and DVII). The monoclonal-monoclonal blend RUM-1/MS26 was the best anti-D reagent used in detecting the D antigen in the IS phase in a tube, reacting with 83.2% of the D variants, while the anti-D blend D175 + 415 was the best monoclonal antibody (MoAb) used in a microplate to minimize the need for an IAT, reacting with 83.2% of the D variants. The D confirmatory tests using SPRCA showed a reactivity (3 - 4+) with 100% of the D variant samples tested. Conclusion: Our results show that, even using sensitive methods and MoAbs to ensure the accurate assignment of the D antigen, at least 17% of our donor samples need a confirmatory D test in order to avoid alloimmunization in D-negative patients.

Serologic strategy in detecting RHD altered alleles in Brazilian blood donors.

BACKGROUND: We evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors. METHODS: We selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spin (IS) with eleven commercially available anti-D reagents in a tube and microplate. The D confirmatory tests for the presence of weak D included the indirect antiglobulin test (IAT) in a tube, gel and solid-phase red blood cell adherence (SPRCA). All DNA samples were extracted from peripheral blood and the D variants were classified using different molecular assays. RESULTS: The RHD variants identified by molecular analysis included weak D types (1, 2, 3, 11 and 38) and partial Ds (DAR1.2, DAR1, DAR3.1, DAU0, DAU2, DAU4, DAU5, DAU6, DMH and DVII). The monoclonal-monoclonal blend RUM-1/MS26 was the best anti-D reagent used in detecting the D antigen in the IS phase in a tube, reacting with 83.2% of the D variants, while the anti-D blend D175 + 415 was the best monoclonal antibody (MoAb) used in a microplate to minimize the need for an IAT, reacting with 83.2% of the D variants. The D confirmatory tests using SPRCA showed a reactivity (3 - 4+) with 100% of the D variant samples tested. CONCLUSION: Our results show that, even using sensitive methods and MoAbs to ensure the accurate assignment of the D antigen, at least 17% of our donor samples need a confirmatory D test in order to avoid alloimmunization in D-negative patients.

Correlation among automated scores of agglutination, antigen density by flow cytometry and genetics of D variants.

BACKGROUND: Laboratory testing to identify the molecular basis of serologic weak D phenotypes is recommended to determine whether a pregnant woman or potential transfusion recipient should be managed as RhD-positive or RhD-negative. The variation in D antigen expression on RBCs, different potencies of anti-D typing reagents, lack of standardized test methods, and the subjectivity of interpreting agglutination reactions complicate the detection of D variants. We evaluated the correlation of agglutination scores by an automated immunoassay analyzer with D antigen densities determined by flow cytometry, and D variant types identified by molecular analysis. MATERIALS AND METHODS: We selected 273 blood donor samples with agglutination scores of less than 92 (4+), measured by an automated analyzer (NEO®, Immucor, Norcross, GA, USA). D antigen densities were measured by flow cytometry for 89 samples. Samples were classified as molecularly-determined weak D or partial D variants by multiplex PCR, PCR RFLP and DNA sequencing. RESULTS: All samples with a D antigen density ≥15% had an agglutination score >80 (4+). Agglutination scores for weak D types varied from 10 to 90. Agglutination scores for partial D antigens were graded with scores varying from 60 to 99. D antigen densities varied from 0.55% to 10.67% for weak Ds and 4.1% to 30.5% for partial Ds. DISCUSSION: Our results showed that score values follow a pattern among D variants that could be related to antigen density and to the RhD variant classification.

Autologous hematopoietic stem cell transplantation in classical Hodgkin's lymphoma

BACKGROUND: Hodgkin's lymphoma has high rates of cure, but in 15 percent to 20 percent of general patients and between 35 percent and 40 percent of those in advanced stages, the disease will progress or will relapse after initial treatment. For this group, hematopoietic stem cell transplantation is considered one option of salvage therapy. OBJECTIVES: To evaluate a group of 106 patients with Hodgkin's lymphoma, who suffered relapse or who were refractory to treatment, submitted to autologous hematopoietic stem cell transplantation in a single transplant center. METHODS: A retrospective study was performed with data collected from patient charts. The analysis involved 106 classical Hodgkin's lymphoma patients who were consecutively submitted to high-dose chemotherapy followed by autologous transplants in a single institution from April 1993 to December 2006. RESULTS: The overall survival rates of this population at five and ten years were 86 percent and 70 percent, respectively. The disease-free survival was approximately 60 percent at five years. Four patients died of procedure-related causes but relapse of classical Hodgkin's lymphoma after transplant was the most frequent cause of death. Univariate analysis shows that sensitivity to pre-transplant treatment and hemoglobin < 10 g/dL at diagnosis had an impact on patient survival. Unlike other studies, B-type symptoms did not seem to affect overall survival. Lactic dehydrogenase and serum albumin concentrations analyzed at diagnosis did not influence patient survival either. CONCLUSION: Autologous hematopoietic stem cell transplantation is an effective treatment strategy for early and late relapse in classical Hodgkin's lymphoma for cases that were responsive to pre-transplant chemotherapy. Refractory to treatment is a sign of worse prognosis. Additionally, a hemoglobin concentration below 10 g/dL at diagnosis of Hodgkin's lymphoma has a negative impact on the survival of patients after transplant. As far as we know this relationship has not been previously reported.

Autologous hematopoietic stem cell transplantation in classical Hodgkin's lymphoma.

BACKGROUND: Hodgkin's lymphoma has high rates of cure, but in 15% to 20% of general patients and between 35% and 40% of those in advanced stages, the disease will progress or will relapse after initial treatment. For this group, hematopoietic stem cell transplantation is considered one option of salvage therapy. OBJECTIVES: To evaluate a group of 106 patients with Hodgkin's lymphoma, who suffered relapse or who were refractory to treatment, submitted to autologous hematopoietic stem cell transplantation in a single transplant center. METHODS: A retrospective study was performed with data collected from patient charts. The analysis involved 106 classical Hodgkin's lymphoma patients who were consecutively submitted to high-dose chemotherapy followed by autologous transplants in a single institution from April 1993 to December 2006. RESULTS: The overall survival rates of this population at five and ten years were 86% and 70%, respectively. The disease-free survival was approximately 60% at five years. Four patients died of procedure-related causes but relapse of classical Hodgkin's lymphoma after transplant was the most frequent cause of death. Univariate analysis shows that sensitivity to pre-transplant treatment and hemoglobin < 10 g/dL at diagnosis had an impact on patient survival. Unlike other studies, B-type symptoms did not seem to affect overall survival. Lactic dehydrogenase and serum albumin concentrations analyzed at diagnosis did not influence patient survival either. CONCLUSION: Autologous hematopoietic stem cell transplantation is an effective treatment strategy for early and late relapse in classical Hodgkin's lymphoma for cases that were responsive to pre-transplant chemotherapy. Refractory to treatment is a sign of worse prognosis. Additionally, a hemoglobin concentration below 10 g/dL at diagnosis of Hodgkin's lymphoma has a negative impact on the survival of patients after transplant. As far as we know this relationship has not been previously reported.

Transplante autólogo de celulas tronco hematopoiéticas nos pacientes com linfoma de Hodgkin: análise de 106 pacientes / Autologous hemapoietic stem cell transplantation in Hodgkin lymphoma: follow-up of 106 patients

Foram analisados 106 pacientes portadores de Linfoma de Hodgkin (LH) com recidiva da doença ou refratários ao tratamento inicial que foram submetidos ao transplante autólogo de células tronco hematopoiéticas (TCTH), na ordem consecutiva de sua realização, entre o mês de abril de 1993 a dezembro de 2007 em um único Centro Brasileiro: o Serviço de Transplante de Medula Óssea da FMUSP. O grupo teve a mediana etária de 28 anos, 55 pacientes (51,9%) eram do sexo masculino e houve predomínio da raça branca (87,6%). A mediana de seguimento clínico foi de 56,4 meses. Todos pacientes foram submetidos no pré TCTH a protocolos de tratamento convencionais, sendo que o uso dos protocolos MOPP, ABVD e sua associação foram utilizados em 97 pacientes (91,5%). Os pacientes foram classificados, de acordo com a resposta ao tratamento utilizado antes do TCTH, sendo 38,1% considerados refratários e 61,9% responsivos. Dos responsivos, 54 pacientes estavam em segunda remissão completa (85%). Tratamento com quimioterapia em alta dose pré TCTH foi feito em 45 (42,4%) dos pacientes (salvamento). A mobilização das células tronco hematopoiéticas foi realizada com ciclofosfamida 120 mg/kg dividida em dois dias seguido de fator estimulador de colônias de granulócitos (G-CSF) na dose de 6 a 17 mcg/kg em 83 (78%) pacientes. Em 25 pacientes (22%) houve falha de mobilização e a coleta foi realizada por múltiplas punções da medula óssea em centro cirúrgico. O valor mediano de células CD 34 coletadas foi de 2,6 x 106 células CD34/Kg de peso do paciente. Os condicionamentos mais utilizados foram BEAM e CVB, e não se encontrou diferença na sobrevida em relação ao regime empregado (p=0,17). A mediana de enxertia das células transplantadas foi de 12 dias. A sobrevida global após o TCTH pelo método de Kaplan-Meier foi, respectivamente, de 86% e 70% aos 5 e 10 anos. Não influenciaram a sobrevida na análise univariada o sexo, o estadio da doença e a presença de massa tumoral extensa...

The study enrolled 106 patients with classic Hodgkin disease (HD) refractory or relapsed after initial treatment who underwent to autologous hematopoietic stem cell transplantation (HSCT) between April 1993 and December 2007. Median age was 28 years and 55 (51,9%) patients were male. Ninety three (87,6%) of patients were white. All patients underwent to conventional chemotherapy protocols prior HSCT. The use of MOPP, ABVD protocols and their associations were used in 97 (91,5%) of the patients. Disease classification was done according to the response to initial treatment and comprised 38,1% refractory and 61,9% responsive patients. In the group of responsive, 54 (85%) patients were in second complete remission. High dose chemotherapy prior HSCT was done as salvage in 45 (42,4%) patients. Stem cell mobilization was done after cyclophosphamide 120mg/kg divided in two days. Granulocyte-colony stimulating factor (G-CSF) 617 mcg/kg was given after cyclophosphamide in 83 (78%) patients. Twenty five (22%) patients failed the mobilization and stem cell harvest was done by bone marrow aspirations. The median number of CD34 collected was 2.6 x 106/L. Preparative regimen mostly used comprised BEAM and CVB and no differences was observed in overall survival (p=0.17). Median time to engraftment was 12 days. Median time of follow-up was 56.4 months. The overall survival (OS) was calculated by the Kaplan-Meier method and was 86% and 70% at 5 and 10 years, respectively. In the univariate analysis, response to initial treatment (p=0.009) and hemoglobin greater than 10g/dL at the time of diagnosis (p=0.02) were factors that influenced better OS. The gender, stage of disease and presence of bulky disease were not significant regarding OS in the univariate analysis. Treatment-related mortality (TRM) in 100-days was 3.74%. The major cause of late mortality was relapse of the disease...