STEVEN SOL WITKIN
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina
71 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 71
- 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.
- Torquetenovirus: predictive biomarker or innocent bystander in pathogenesis(2023) TOZETTO-MENDOZA, Tania Regina; BRAZ-SILVA, Paulo Henrique; GIANNECCHINI, Simone; WITKIN, Steven S.
- The vaginal microbiome in pregnant women: knowledge gaps in relation to clinical relevance(2021) WITKIN, S. S.; MORON, A. F.; LINHARES, I. M.; SKUPSKI, D. W.
- The Torque Teno Virus Titer in Saliva Reflects the Level of Circulating CD4(+) T Lymphocytes and HIV in Individuals Undergoing Antiretroviral Maintenance Therapy(2022) HONORATO, Layla; WITKIN, Steven S.; MENDES-CORREA, Maria Cassia; TOSCANO, Ana Luiza Castro Conde; LINHARES, Iara Moreno; PAULA, Anderson Vicente de; PAIAO, Heuder Gustavo Oliveira; PAULA, Vanessa Salete de; LOPES, Amanda de Oliveira; LIMA, Silvia Helena; RAYMUNDI, Vanessa de Cassia; FERREIRA, Noely Evangelista; SILVA JUNIOR, Almir Ribeiro da; ABRAHIM, Karim Yaqub; BRAZ-SILVA, Paulo Henrique; TOZETTO-MENDOZA, Tania ReginaIntroductionTorque teno virus (TTV) is a non-pathogenic virus present in body fluids. Its titer in the circulation increases in association with immune suppression, such as in HIV-infected individuals. We evaluated if the TTV titer in saliva from HIV-positive individuals undergoing antiretroviral therapy (ART) was related to the circulating CD4+ T lymphocyte concentration and the HIV titer. MethodsSaliva was collected from 276 asymptomatic individuals undergoing ART, and an additional 48 individuals positive for AIDS-associated Kaposi's Sarcoma (AIDS-KS). The salivary TTV titer was measured by gene amplification analysis. The circulating CD4+ T lymphocyte and HIV levels were obtained by chart review. ResultsTTV was detectable in saliva from 80% of the asymptomatic subjects and 87% of those with AIDS-KS. In the asymptomatic group the median log(10) TTV titer/ml was 3.3 in 200 males vs. 2.4 in 76 females (p < 0.0001). TTV titer/ml was 3.7 when HIV was acquired by intravenous drug usage, 3.2 when by sexual acquisition and 2.4 when blood transfusion acquired. The salivary TTV titer was inversely correlated with the circulating CD4+ T lymphocyte level (p < 0.0001) and positively correlated with the circulating HIV concentration (p = 0.0005). The median salivary TTV titer and circulating HIV titer were higher, and the CD4+ count was lower, in individuals positive for AIDS-KS than in the asymptomatic subjects (p < 0.0001). ConclusionThe TTV titer in saliva is a potential biomarker for monitoring immune status in individuals undergoing ART.
- Relationship between Papillomavirus vaccine, vaginal microbiome, and local cytokine response: an exploratory research(2021) GIRALDO, Paulo Cesar; SANCHES, Jose Marcos; SPARVOLLI, Luiz Gustavo; AMARAL, Rose; MIGLIORINI, Isabel; GIL, Cristiane Damas; TADDEI, Carla Romano; WITKIN, Steven S.; DISCACCIATI, Michelle GarciaIntroduction The influence of vaccination on composition of the human microbiome at distinct sites has been recognized as an essential component in the development of new vaccine strategies. The HPV vaccine is widely used to prevent cervical cancer; however, the influence of HPV vaccine on the vaginal microbiota has not been previously investigated. In his study, we performed an initial characterization of the microbiome and cytokine composition in the vagina following administration of the bivalent vaccine against HPV 16/18. Material and methods In this exploratory study, fifteen women between 18 and 40 years received three doses of the HPV-16/18 AS04-adjuvanted vaccine (Cervarix (R)). Cervicovaginal samples were collected before the first dose and 30 days after the third dose. HPV genotyping was performed by the XGEN Flow Chip technique. The cytokines IFN-gamma, IL-2, IL-12p70, TNF-alpha, GM-CSF, IL-4, IL-5, IL-10, and IL-13 were quantitated by multiplex immunoassay. The vaginal microbiome was identified by analysis of the V3/V4 region of the bacterial 16S rRNA gene. Results The most abundant bacterial species in the vaginal microbiome was Lactobacillus crispatus, followed by L. iners. Bacterial diversity and dominant organisms were unchanged following vaccination. Small decreases in levels of pro and anti-inflammatory cytokines were observed following HPV vaccination, but there was no association between vaginal cytokine levels and microbiome composition. Conclusion Vaginal microbiome is not altered following administration of the standard three-dose HPV-16/18 AS04-adjuvanted (Cervarix (R)) vaccine.
- Prevalence and diagnostic accuracy of microcephaly in a pediatric cohort in Brazil: a retrospective cross-sectional study(2021) BERTOZZI, Ana Paula Antunes Pascalicchio; GAZETA, Rosa Estela; FAJARDO, Thamirys Cosmo Gillo; MORON, Antonio Fernandes; SORIANO-ARANDES, Antoni; ALARCON, Ana; GARCIA-ALIX, Alfredo; SILVA, Alify Bertoldo da; FLORENCE FILHO, Nemesio; SARMENTO, Stephanno Gomes Pereira; WITKIN, Steven S.; PASSOS, Saulo DuarteObjective: We sought to describe the prevalence of microcephaly and to compare the different cutoff points established by the Brazilian Ministry of Health at various times during a Zika virus epidemic. As a secondary aim, we investigated the possible etiology of the microcephaly. Method: This retrospective study utilized newborn participants in the Zika Cohort Study Jundiai. Newborns from the Zika Cohort Study Jundiai with an accurate gestational age determination and complete anthropometric data were analyzed, and microcephaly was diagnosed according to the INTERGROWTH-21st curve. At delivery, fluids were tested for specific antibodies and for viruses. Brain images were evaluated for microcephaly. Receiver Operating Characteristic curves were plotted to define the accuracy of different cutoff points for microcephaly diagnosis. Results: Of 462 eligible newborns, 19 (4.1%) were positive for microcephaly. Cutoff points corresponding to the curves of the World Health Organization yielded the best sensitivity and specificity. Three of the microcephaly cases (15.8%) were positive for Zika virus infections; nine (47.4%) had intrauterine growth restriction; one had intrauterine growth restriction and was exposed to Zika virus; three had a genetic syndrome (15.8%); and three had causes that had not been determined (15.8%). Conclusions: Microcephaly prevalence was 4.1% in this study. Cutoff values determined by the World Health Organization had the highest sensitivity and specificity in relation to the standard IG curve. The main reason for microcephaly was intrauterine growth restriction. All possible causes of microcephaly must be investigated to allow the best development of an affected baby. (C) 2020 Sociedade Brasileira de Pediatria.
- Influence of recurrent vulvovaginal candidiasis on quality of life issues(2019) I, Eiko Fukazawa; WITKIN, Steven S.; ROBIAL, Renata; VINAGRE, Joao G.; BARACAT, Edmund C.; LINHARES, Iara M.Purpose More than 370 million women will experience recurrent vulvovaginal candidiasis (RVVC) during their lifetime. However, RVVC is often trivialized as clinically insignificant and not worthy of research funding. We evaluated the influence of RVVC on the quality of life in affected women. Methods The validated World Health Organization Quality of Life Abbreviated Assessment (WHOQOL-Bref) questionnaire was administered to 100 women with RVVC and to 101 epidemiologically matched women with no history of vulvovaginal candidiasis. RVVC was defined as at least four episodes of clinical and culture-positive vaginal candidiasis within a 1 year period. Data were analyzed by Chi square, Student t test and analysis of variance. Internal consistency of responses to questions was evaluated by Cronbach alpha. Results The Cronbach alpha coefficient was > 0.80 for responses to generalized questions and > 0.65 for answers to more specific questions, indicating substantial internal consistency. Perception of quality of life and satisfaction with their health was greatly reduced in the RVVC group (p < 0.001). Diminished responses to physical and psychological well-being were also reported by women with RVVC (p < 0.001). Various aspects of social relations including sexual activity were similarly reduced (p < 0.001) as were satisfaction with issues such as home environment, financial resources and employment (p < 0.001). Conclusion RVVC affects multiple aspects of a woman's well-being. Women with this condition deserve serious attention from clinicians and research into susceptibility, prevention and treatment of this infection deserves much greater emphasis.
- Association between torquetenovirus in vaginal secretions and infertility: An exploratory metagenomic analysis(2023) COSTA, A. Charlys Da; BORTOLETTO, Pietro; SPANDORFER, Steven D.; TOZETTO-MENDOZA, Tania Regina; LINHARES, Iara M.; MENDES-CORREA, Maria Cassia; WITKIN, Steven S.ProblemThe association of viruses with infertility remains incompletely evaluated.Method of studyVaginal secretions from 46 women seeking treatment in the Center for Reproductive Medicine and Infertility at Weill Cornell Medicine were tested for viruses by metagenomic analysis by lab personnel blinded to all clinical data.ResultsTorquetenovirus (TTV) was identified in 16 women, alphapapillomavirus in seven women and most were positive for bacteriophages. Twelve of the subjects were fertile and sought to freeze their oocytes for future implantation. These women were all negative for TTV. In contrast, 16 of the 34 women (47.1%) being treated for infertility were TTV-positive (p = .0035). Evaluating the women by cause of infertility, five of nine women (55.6%) whose male partner had inadequate sperm parameters and six of 14 women (42.9%) with defective ovulation were TTV positive (p = .0062 and p = .0171, respectively, vs. the fertile women). Alphapapillomavirus was identified in one (8.3%) fertile woman, five (35.7%) women with ovulation deficiency, and one (11.1%) woman with male factor infertility. These differences were not statistically significant. There were no differences in bacteriophage families or the presence of Lactobacillus phages between fertile or infertile women or between different causes of infertility. There was a negative association between TTV detection and Lactobacillus crispatus dominance in the vaginal microbiota (p = .0184), but no association between TTV detection and the presence of alphapapillomavirus or Candida species.ConclusionDetection of TTV in the vagina might be a biomarker for specific causes of infertility.
- Influence of Lactobacillus crispatus, Lactobacillus iners and Gardnerella vaginalis on bacterial vaginal composition in pregnant women(2021) WITKIN, Steven S.; MORON, Antonio F.; LINHARES, Iara M.; FORNEY, Larry J.Purpose To investigate associations between bacterial species in the vagina in mid-trimester pregnant women from Brazil. Methods The vaginal microbiome in 613 subjects was identified by analysis of the V1-V3 region of bacterial 16S ribosomal RNA and the relative prevalence of individual bacteria were determined. Results The bacterial species present in the greatest number of women were Lactobacillus crispatus (306 women), L. iners (298 women) and Gardnerella vaginalis (179 women). When present in the vagina, L. crispatus was the most abundant bacterium more than 85% of the time. In contrast, L. iners and G. vaginalis were most abundant in 63% and 41% of women who were positive for these microorganisms, respectively (p < 0.0001 vs. L. crispatus). The proportion of L. crispatus was negatively associated with the proportions of L. iners, L. jensenii, L. gasseri, G. vaginalis, Megasphaera, Atopobium vaginae and Prevotella (p < 0.0001). In contrast, the proportion of G. vaginalis was positively associated with levels of Megasphaera, A. vaginae and Prevotella (p < 0.0001) while L. iners proportion was unrelated to the proportion of L. jensenii, G. vaginalis, Megasphaera, A. vaginae or Prevotella. Conclusion The composition of the vaginal microbiota in mid-trimester pregnant women is influenced by the relative concentrations of L. crispatus, L. iners and G. vaginalis.