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- Detection and analysis of blood donors seropositive for syphilis(2021) ATTIE, Adriana; ALMEIDA-NETO, Cesar de; WITKIN, Steven S.; DERRIGA, Juliana; NISHIYA, Anna S.; FERREIRA, Jerenice E.; COSTA, Natalia de Souza Xavier; SALLES, Nanci Alves; FACINCANI, Tila; LEVI, Jose E.; SABINO, Ester C.; ROCHA, Vanderson; MENDRONE-JR, Alfredo; FERREIRA, Suzete C.Background The increasing incidence of syphilis worldwide has called attention to the risk of transmission by transfusion. Aims To determine the prevalence of active syphilis in blood donors and characterise the serological profile of syphilis-positive donors. Methods Samples positive for Treponema pallidum using the chemiluminescent microparticle immunoassay (CMIA) during blood donor screening from 2017 to 2018 were tested by the Venereal Disease Research Laboratory (VDRL) non-treponemal test and for anti-T. pallidum IgM by ELISA (Immunoassay Enzyme test for detection of IgM antibodies). The INNO-LIA Syphilis test (Line Immuno Assay solid test for confirmation antibodies to Treponema pallidum) was performed as a confirmatory test on samples that were positive on ELISA-IgM but negative on VDRL. ELISA-IgM (+) samples were also tested for T. pallidum DNA in sera by real-time polymerase chain reaction (PCR). Results Of 248 542 samples screened, 1679 (0.67%) were positive for syphilis by CMIA. Further analysis was performed on 1144 (68.1%) of these samples. Of those tested, 16% were ELISA IgM(+)/VDRL(+), 16.5% were ELISA IgM(-)/VDRL(+), 4.1% were ELISA IgM(+)/VDRL(-), and 63.4% were ELISA IgM (-)/VDRL(-). The INNO-LIA Syphilis test results were 33 (3%) positive, 2 (0.2%) undetermined and 12 (1%) negative. Of the 230 EIA-IgM(+) samples (20.1%), 5 (2.2%) were PCR positive. The prevalence of active syphilis in 2017 and 2018 was 0.1% and 0.07%, respectively, and overall prevalence of serologic markers for syphilis was highest among male, unmarried, 25-34-year-olds with a high school education and who were first-time donors. Conclusion There is a risk of transfusion-transmitted syphilis in blood banks that exclusively use the VDRL test for donor screening, as is currently the situation in some Brazilian blood centres, as well as in other blood centres around the world.
- Prevalence and clinical consequences of Hepatitis C virus infection in patients undergoing hematopoietic stem cell transplantation(2024) DIAZ, Ana Claudia Marques Barbosa; WITKIN, Steven Sol; ALMEIDA-NETO, Cesar de; MENDRONE-JUNIOR, Alfredo; ROCHA, Vanderson; COSTA, Silvia Figueiredo; RAMOS, Jessica Fernandes; MENDES-CORREA, Maria CassiaHepatitis C virus (HCV) infection is a significant cause of morbidity and mortality among hematopoietic stem cell transplant (HCT) recipients. In Brazil, its occurrence in HCT recipients remains undetermined. We now report on HCV prevalence in HCT recipients and its clinical consequences. The medical records of all HCT recipients seen at Hospital das Clinicas, Sao Paulo University Medical School, from January 2010 to January 2020 were reviewed to determine HCV serostatus. A retrospective analysis of medical charts was undertaken on all seropositive cases to determine HCV genotype, presence of liver fibrosis, co-infections with other viruses, previous treatments, and clinical evolution of liver pathology after HCT. Of the 1,293 HCT recipients included in the study, seven (0.54%) were HCV antibody-positive and five (0.39%) were also viremic for HCV-RNA. Four of these individuals had moderate to severe liver fibrosis (METAVIR F2/F3) and one was cirrhotic. Two of the viremic patients developed acute liver dysfunction following transplantation. All patients had their acute episode of liver dysfunction resolved with no further complications. Four of the viremic patients were treated for HCV infection with direct acting agents (DAA). Information regarding HCV treatment was lacking for one of the viremic HCV patients due to loss of follow up. Sustained anti-virologic responses were observed in three cases after the use of DAA. The detection of HCV in hematological adults undergoing HCT and its successful treatment with DAA highlight the necessity of testing for HCV both prior to and following transplantation.
- Immunogenicity of personalized dendritic-cell therapy in HIV-1 infected individuals under suppressive antiretroviral treatment: interim analysis from a phase II clinical trial(2022) BAPTISTA, Marcella Vassao de Almeida; SILVA, Lais Teodoro da; SAMER, Sadia; OSHIRO, Telma Miyuki; SHYTAJ, Iart Luca; GIRON, Leila B.; PENA, Nathalia Mantovani; CRUZ, Nicolly; GOSUEN, Gisele Cristina; FERREIRA, Paulo Roberto Abrao; CUNHA-NETO, Edecio; GALINSKAS, Juliana; DIAS, Danilo; SUCUPIRA, Maria Cecilia Araripe; ALMEIDA-NETO, Cesar de; SALOMAO, Reinaldo; DUARTE, Alberto Jose da Silva; JANINI, Luis Mario; HUNTER, James R.; SAVARINO, Andrea; JULIANO, Maria Aparecida; DIAZ, Ricardo SobhieBackground: We developed a personalized Monocyte-Derived Dendritic-cell Therapy (MDDCT) for HIV-infected individuals on suppressive antiretroviral treatment and evaluated HIV-specific T-cell responses. Methods: PBMCs were obtained from 10 HIV+ individuals enrolled in trial NCT02961829. Monocytes were differentiated into DCs using IFN-alpha and GM-CSF. After sequencing each patient's HIV-1 Gag and determining HLA profiles, autologous Gag peptides were selected based on the predicted individual immunogenicity and used to pulse MDDCs. Three doses of the MDDCT were administered every 15 days. To assess immunogenicity, patients' cells were stimulated in vitro with autologous peptides, and intracellular IL-2, TNF, and interferon-gamma (IFN-gamma) production were measured in CD4(+) and CD8(+)T-cells. Results: The protocol of ex-vivo treatment with IFN-a and GM-CSF was able to induce maturation of MDDCs, as well as to preserve their viability for reinfusion. MDDCT administration was associated with increased expression of IL-2 in CD4(+) and CD8(+)T-cells at 15 and/or 30 days after the first MDDCT administration. Moreover, intracellular TNF and IFN-gamma expression was significantly increased in CD4(+) T-cells. The number of candidates that increased in vitro the cytokine levels in CD4(+) and CD8(+)T cells upon stimulation with Gag peptides from baseline to day 15 and from baseline to day 30 and day 120 after MDDCT was significant as compared to Gag unstimulated response. This was accompanied by an increasing trend in the frequency of polyfunctional T-cells over time, which was visible when considering both cells expressing two and three out of the three cytokines examined. Conclusions: MDDC had a mature profile, and this MDDCT promoted in-vitro T-cell immune responses in HIV-infected patients undergoing long-term suppressive antiretroviral treatment.
- Demographic characteristics and prevalence of serologic markers among blood donors who use confidential unit exclusion (CUE) in Sao Paulo, Brazil: implications for modification of CUE polices in Brazil(2011) ALMEIDA-NETO, Cesar de; LIU, Jing; WRIGHT, David J.; MENDRONE-JUNIOR, Alfredo; TAKECIAN, Pedro L.; SUN, Yu; FERREIRA, Joao Eduardo; CHAMONE, Dalton de Alencar Fischer; BUSCH, Michael P.; SABINO, Ester CerdeiraBACKGROUND: This study evaluated demographic profiles and prevalence of serologic markers among donors who used confidential unit exclusion (CUE) to assess the effectiveness of CUE and guide public policies regarding the use of CUE for enhancing safety versus jeopardizing the blood supply by dropping CUE. STUDY DESIGN AND METHODS: We conducted a cross-sectional analysis of whole blood donations at a large public blood center in Sao Paulo from July 2007 through June 2009, compared demographic data, and confirmed serologic results among donors who used and who have never used CUE (CUE never). RESULTS: There were 265,550 whole blood units collected from 181,418 donors from July 2007 through June 2009. A total of 9658 (3.6%) units were discarded, 2973 (1.1%) because CUE was used at the current donation (CUE now) and 6685 (2.5%) because CUE was used in the past (CUE past). The CUE rate was highest among donors with less than 8 years of education (odds ratio [OR], 2.78; 95% confidence interval [CI], 2.51-3.08). CUE now donations were associated with higher positive infectious disease marker rates than CUE never donations (OR, 1.41; CI, 1.13-1.77), whereas CUE past donations were not (OR, 1.04; CI, 0.75-1.45). CONCLUSION: The CUE process results in a high rate of unit discard. CUE use on an individual donation appears predictive of a high-risk marker-positive donation and, thus, appears to contribute modestly to blood safety. The policy of discarding units from donors who have previously CUE-positive donations does not improve safety and should be discontinued.
- Detection of unreported usage of the antiretroviral drug lamivudine in two blood donors(2023) NISHIYA, Anna; SALLES, Nanci; ALMEIDA-NETO, Cesar de; FERREIRA, Suzete; NOGUEIRA, Fatima; ROCHA, Vanderson; MENDRONE, AlfredoBackground Unreported HIV antiretroviral (ARV) drug usage by blood donors compromises the ability to detect evidence of HIV infection in blood screening tests and represents a risk for blood transfusion safety. Our objective was to determine the frequency of undeclared ARV drug use by blood donors with altered HIV markers.Study Design and Methods This was a retrospective cross-sectional analysis of donations that were tested for HIV antibody (ab), antigen (ag), and RNA by chemiluminescent immunoassay and nucleic acid screening tests. Positive samples were retested and were subjected to ARV drug testing by high-performance liquid chromatography-tandem mass spectrometry.Results Of 345,252 blood donations, 361 (0.1%) were positive on initial testing. Samples from 296 (81.9%) of these donations were available for further analysis. The presence of HIV ab/ag and/or RNA was confirmed in 83 (28.0%) of these samples. All 296 bloods were subjected to ARV testing. The ARV drug lamivudine, at 11.3 and 6.7 ng/mL, was detected in 2 of 83 (2.4%) donations that were HIV positive. Other drugs were not detected.Conclusion Unreported ARV usage was identified in two candidates for blood donation. More intensive efforts to educate donors about disclosure and to investigate the extent of this phenomenon in Brazil are needed.
- Molecular characterization of viruses associated with encephalitis in Sao Paulo, Brazil(2019) FERREIRA, Jerenice E.; FERREIRA, Suzete C.; ALMEIDA-NETO, Cesar; NISHIYA, Anna S.; ALENCAR, Cecilia S.; GOUVEIA, Gisele R.; CAIAFFA-FILHO, Helio; GOMES, Helio; SANTOSID, Raimunda Telma de Macedo; WITKIN, Steven S.; MENDRONE-JUNIOR, Alfredo; SABINO, Ester C.The objective of this study was to characterize the prevalence of viral encephalitis due to arbovirus infection of the Togaviridae and Flaviviridae families in Sao Paulo, Brazil. A total of 500 cerebrospinal fluid (CSF) samples collected between August 2012 and January 2013, from patients with symptoms of acute encephalitis were analyzed. Findings suggestive of viral encephalitis-elevations in cell concentration, glucose and total protein-were observed in 234 (46.8%) samples, designated as Group 1. The remaining 266 samples comprised Group 2. All samples were tested for Flaviviruses (dengue virus 1, 2, 3 and 4, yellow fever virus and West Nile virus), Alphavirus (NS5 region) and enterovirus by RT-PCR and for herpesviruses and enteroviruses using CLART(-)Entherpex. A presumptive viral etiological agent was detected in 26 samples (5.2%), 18 (8.0%) in Group 1 and 8 (3.0%) in Group 2. In Group 1 human herpesviruses were detected in 9 cases, enteroviruses in 7 cases, dengue viruses (DENV) in 2 CSFs and St. Louis encephalitis virus (SLEV) in one case. In Group 2 there were 3 CSFs positive for human herpesviruses, 2 for enteroviruses, 2 for DENV and 1 for SLEV. Detection of arboviruses, even though present in a minority of infected patients, identifies these viruses as a probable etiological agent of encephalitis. This is of special concern in regions where this class of viruses is endemic and has been linked to other recent epidemics.
- Characterization of HIV risks in a Brazilian sickle cell disease population(2020) BLATYTA, P. F.; KELLY, S.; GONCALEZ, T. T.; CARNEIRO-PROIETTI, A. B.; SALOMON, T.; MIRANDA, C.; SABINO, E.; PREISS, L.; MAXIMO, C.; LOUREIRO, P.; CUSTER, B.; ALMEIDA-NETO, C. deBackground A low prevalence of HIV in sickle cell disease (SCD) patients has been reported in the literature though mechanisms for this are not understood. Methods HIV risk behaviors were compared between SCD cases and non-SCD controls using a self-administered audio computer-assisted self-interview. SCD cases were recruited from a multi-center SCD cohort established in Brazil; controls were recruited from SCD social contacts. Categorical variables were analyzed using Chi-Square or Fisher exact test. Continuous variables were compared using the Mann-Whitney U test. Results There were 152 SCD cases and 154 age/location matched controls enrolled at three participating Brazilian centers during 2016-17. No significant differences in number of sexual partners (lifetime or previous 12 months), male-to-male sex partners or intravenous drug use were observed. Cases received more transfusions, surgeries, and acupuncture treatment. Conclusions Besides the risk of transfusion-transmitted HIV, which is now exceedingly rare, SCD and non-SCD participants demonstrated similar HIV risk behaviors. Causes other than risk behaviors such as factors inherent to SCD pathophysiology may explain the reported low prevalence of HIV in SCD.
- Evaluation of a High Throughput Method for the Detection of Mutations Associated with Thrombosis and Hereditary Hemochromatosis in Brazilian Blood Donors(2015) NIEWIADONSKI, Vivian Dionisio Tavares; BIANCHI, Juliana Vieira dos Santos; ALMEIDA-NETO, Cesar de; GABURO JR., Nelson; SABINO, Ester CerdeiraBackground The aim of this study was to evaluate the OpenArray platform for genetic testing of blood donors and to assess the genotype frequencies of nucleotide-polymorphisms (SNPs) associated with venous thrombosis (G1691A and G20210A), hyperhomocysteinemia (C677T, A1298C), and hereditary hemochromatosis (C282Y, H63D and S65C) in blood donors from Sao Paulo, Brazil. Methods We examined 400 blood donor samples collected from October to November 2011. The SNPs were detected using OpenArray technology. The blood samples were also examined using a real-time PCR-FRET system to compare the results and determine the accuracy of the OpenArray method. Results We observed 100% agreement in all assays tested, except HFE C282Y, which showed 99.75% agreement. The HFE C282Y assay was further confirmed through direct sequencing, and the results showed that OpenArray analysis was accurate. The calculated frequencies of each SNP were FV G1691A 98.8% (G/G), 1.2% (G/A); FII G2021A 99.5% (G/G), 0.5% (G/A); MTHFR C677T 45.5%(C/C), 44.8% (C/T), 9.8% (T/T); MTHFR A1298C 60.3% (A/A), 33.6% (A/C), 6.1% (C/C); HFE C282Y 96%(G/G), 4%(G/A), HFE H63D 78.1%(C/C), 20.3% (C/G), 1.6% (G/G); and HFE S65C 98.1%(A/A), 1.9% (A/T). Conclusion Taken together, these results describe the frequencies of SNPs associated with diseases and are important to enhance our current knowledge of the genetic profiles of Brazilian blood donors, although a larger study is needed for a more accurate determination of the frequency of the alleles. Furthermore, the OpenArray platform showed a high concordance rate with standard FRET RT-PCR.
- HCV Genotypes, Characterization of Mutations Conferring Drug Resistance to Protease Inhibitors, and Risk Factors among Blood Donors in Sao Paulo, Brazil(2014) NISHIYA, Anna S.; ALMEIDA-NETO, Cesar de; FERREIRA, Suzete C.; ALENCAR, Cecilia S.; DI-LORENZO-OLIVEIRA, Claudia; LEVI, Jose E.; SALLES, Nanci A.; MENDRONE JR., Alfredo; SABINO, Ester C.Background: Hepatitis C virus (HCV) infection is a global health problem estimated to affect almost 200 million people worldwide. The aim of this study is to analyze the subtypes and existence of variants resistant to protease inhibitors and their association with potential HCV risk factors among blood donors in Brazil. Methods: Repeat anti-HCV reactive blood donors are systematically asked to return for retest, notification, and counseling in which they are interviewed for risk factors for transfusion-transmitted diseases. We analyzed 202 donors who returned for counseling from 2007 to 2010 and presented enzyme immunoassay-and immunoblot-reactive results. The HCV genotypes and resistance mutation analyses were determined by the direct sequencing of the NS5b and NS3 regions, respectively. The HCV viral load was determined using an in-house real-time PCR assay targeting the 5'-NCR. Results: HCV subtypes 1b, 1a, and 3a were found in 45.5%, 32.0%, and 18.0% of the donors, respectively. The mean viral load of genotype 1 was significantly higher than that of the genotype 3 isolates. Subtype 1a was more frequent among young donors and 3a was more frequent among older donors. Protease inhibitor-resistant variants were detected in 12.8% of the sequenced samples belonging to genotype 1, and a higher frequency was observed among subtype 1a (20%) in comparison to 1b (8%). There was no difference in the prevalence of HCV risk factors among the genotypes or drug-resistant variants. Conclusions: We found a predominance of subtype 1b, with an increase in the frequency of subtype 1a, in young subjects. Mutations conferring resistance to NS3 inhibitors were frequent in treatment-naive blood donors, particularly those infected with subtype 1a. These variants were detected in the major viral population of HCV quasispecies, have replicative capacities comparable to nonresistant strains, and could be important for predicting the response to antiviral triple therapy.
- Tools to implement and improve blood donor hemovigilance in Brazil(2014) ALMEIDA NETO, Cesar de