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Dive into the research topics where Sandra Helena Alves Bonon is active.

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Featured researches published by Sandra Helena Alves Bonon.


Clinics | 2011

Simultaneous monitoring of CMV and human herpesvirus 6 infections and diseases in liver transplant patients: one-year follow-up

Fernanda Aparecida Costa; Marcelo Naoki Soki; Paula Durante Andrade; Sandra Helena Alves Bonon; Ronaldo Luis Thomasini; A.M. Sampaio; Marcelo de Carvalho Ramos; Cláudio Lúcio Rossi; Teresa Cristina Cavalcanti; Ilka de Fátima Santana Boin; Marília Leonard; Luiz Sérgio Leonard; R.S.B. Stucchi; Sandra Cecília Botelho Costa

OBJECTIVE: The aim of this study was to simultaneously monitoring cytomegalovirus and human herpesvirus 6 active infections using nested-polymerase chain reaction and, together with clinical findings, follow the clinical status of patients undergoing liver transplant. INTRODUCTION: The human β-herpesviruses, including cytomegalovirus and human herpesvirus 6, are ubiquitous among human populations. Active infections of human herpesvirus 6 and cytomegalovirus are common after liver transplantation, possibly induced and facilitated by allograft rejection and immunosuppressive therapy. Both viruses affect the success of the transplant procedure. METHODS: Thirty patients submitted to liver transplant at the Liver Transplant Unit, at the Gastro Center, State University of Campinas, SP, Brazil, were studied prospectively from six months to one year, nested-polymerase chain reaction for cytomegalovirus and human herpesvirus 6 DNA detections. Two or more consecutive positive nested-polymerase chain reaction were considered indicative of active infection. RESULTS: Active infection by cytomegalovirus was detected in 13/30 (43.3%) patients, median time to first cytomegalovirus detection was 29 days after transplantation (range: 0-99 days). Active infection by human herpesvirus 6 was detected in 12/30 (40%) patients, median time to first human herpesvirus 6 detection was 23.5 days after transplantation (range: 0-273 days). The time-related appearance of each virus was not statistically different (p = 0.49). Rejection of the transplanted liver was observed in 16.7% (5/30) of the patients. The present analysis showed that human herpesvirus 6 and/or cytomegalovirus active infections were frequent in liver transplant recipients at our center. CONCLUSIONS: Few patients remain free of betaherpesviruses after liver transplantation. Most patients presenting active infection with more than one virus were infected sequentially and not concurrently. Nested-polymerase chain reaction can be considered of limited value for clinically monitoring cytomegalovirus and human herpesvirus 6.


web science | 2013

Cytomegalovirus (CMV) genotype in allogeneic hematopoietic stem cell transplantation

Débora de Campos Dieamant; Sandra Helena Alves Bonon; Renata Mb Peres; Cláudia Raquel Cantarelli Costa; Dulcineia M. Albuquerque; Eliana Cristina Martins Miranda; Francisco J.P. Aranha; Gislaine Oliveira-Duarte; Virginio C. A. Fernandes; Carmino Antonio de Souza; Sandra Cecília Botelho Costa; Afonso Celso Vigorito

BackgroundBased on sequence variation in the UL55 gene that encodes glycoprotein B (gB), human cytomegalovirus (CMV) can be classified into four gB genotypes. Previous studies have suggested an association between CMV gB genotype and clinical outcome in patients who underwent an allogeneic hematopoietic stem cell transplant (HSCT). The goals of this study were identify patients with active infection caused by CMV in recipients of HSCT; determine the prevalence of CMV genotypes in the study group; correlate genotype with CMV disease, acute GVHD and overall survival.MethodsThe diagnosis of active CMV infection after allogeneic HSCT was detected by antigenemia (AGM) and/or nested-PCR (N-PCR). Positive samples from patients with active CMV infection were submitted to genotyping using N-PCR to amplify a region of UL55, followed by restriction analysis based on HinfI and RsaI digestion. Real-time PCR (qPCR) was used to determine the viral load during active CMV infection and antiviral treatment.ResultsSixty-three allogeneic HSCT recipients were prospectively evaluated; 49/63 (78%) patients were infected with CMV genotypes – gB1 19/49 (39%), gB2 17/49 (35%), gB3 3/49 (6%), gB4 7/49 (14%) – and 3 (6%) had mixed CMV genotypes (gB1 + gB3, gB1 + gB4 and gB2 + gB4). Characterized by gastrointestinal disease, CMV disease occurred in 3/49 (6.1%) patients, who had CMV gB3 genotype. These gB3 genotype patients presented an increasing AGM number, mean 125 (± 250) (P = 0.70), and qPCR copies/ml, mean 37938 (SD ± 50542) (P = 0.03), during antiviral treatment, when compared with other CMV genotypes. According to CMV genotypes, stratified overall survival was 55% for gB1, 43% for gB2; 0% for gB3 and 57% for gB4 (P = 0.03).ConclusionsOne of the restrictions of the presented study was the low number of CMV gB sub-cohorts). However, we demonstrated that the frequency of active CMV infection in this HSCT population was high, and the most prevalent genotype in these patients with active CMV infection was gB1 and gB2 genotype (74%). In Brazil, HSCT recipients seem to carry mainly gB1 and gB2 CMV genotype.


Transplantation Proceedings | 2011

Monitoring and Detection of Cytomegalovirus in Liver Transplant Recipients

Arlete Milan; A.M. Sampaio; A.C. Guardia; Célia Regina Pavan; Paula Durante Andrade; Sandra Helena Alves Bonon; Sandra Cecília Botelho Costa; E.C. Ataide; I.F.S.F. Boin; R.S.B. Stucchi

Cytomegalovirus (CMV) is a β-herpesvirus. CMV infections are a common complication contributing to morbidity and mortality after liver transplantation. Among organ transplant recipients, CMV can reactivate from latency during the first 6 months. This prospective study performed from February 2008 to December 2009 examined liver transplant recipients during the first 6 months. Two methods were performed to detect CMV infections: antigenemia (AGM) and nested (PCR). Ninety-four patients, including 72 men (76.6%) and 22 women (23.4%) underwent liver transplantation during this period. We analyzed 575 samples including 465 for AGM and PCR. Forty-three (9.25%) showed positive AGM as detected 2 to 179 days posttransplantation with a mean of 50 days and a median of 35 days, and 93/465 (20%) showed positive PCR at 0 to 186 days posttransplantation with a mean of 31 days and a median of 38 days. Among the 43 antigenemia patients, 38 samples were positive for up to 5 cells 18 of which were PCR-positive. Five samples were positive with more than 5 cells, including 3 that were PCR-positive. Only 4.51% had AGM and were PCR-positive in the same sample. Despite only 9.25% (43/465) showing AGM, the current study suggested the utility of routine monitoring to detect early CMV infection among liver transplantation patients seeking to reduce morbidity and mortality.


Current Eye Research | 2015

Dexamethasone/Povidone Eye Drops versus Artificial Tears for Treatment of Presumed Viral Conjunctivitis: A Randomized Clinical Trial

Roberto Damian Pacheco Pinto; Rodrigo Pessoa Cavalcanti Lira; Ricardo Yuji Abe; Rafael Santos Zacchia; João Paulo Fernandes Felix; Andre Venancio Fernandes Pereira; Carlos Eduardo Leite Arieta; Rosane Silvestre de Castro; Sandra Helena Alves Bonon

Abstract Purpose: To determine whether topical dexamethasone 0.1%/povidone-iodine 0.4% reduces the duration of presumed viral conjunctivitis better than artificial tears and whether the treatment relieves the symptoms of this disease. Methods: Randomized, masked and controlled trial. One-hundred twenty-two patients with a clinical diagnosis of presumed viral conjunctivitis were randomized to either the treatment group or the control group. Physicians and patients were masked to the treatment. Swabs were taken from the conjunctival fornix for adenovirus PCR analyses. Patients in the treatment group received topical dexamethasone 0.1%/povidone-iodine 0.4% eye drops four times daily, and patients in the placebo group received artificial tears four times daily, both for seven days. Symptoms were recorded on the day of recruitment and at the time of a follow-up examination 5, 10 and 30 d later. The main outcome was duration of the disease. The others outcomes were overall discomfort, itching, foreign body sensation, tearing, redness, eyelid swelling, side effects of the eye drops, intraocular pressure and the incidence of subepithelial corneal infiltrates. Results: There was no statistically significant difference between the treatment group and the control group in terms of the patients’ symptoms, intraocular pressure and incidence of subepithelial cornea infiltrates during the entire follow-up period. Patients of the treatment group reported more stinging (p < 0.001) and a shorter conjunctivitis duration (9.4 ± 4.6 d in the dexamethasone 0.1%/povidone-iodine 0.4% group versus 11.8 ± 4.9 d in the artificial tears group, p = 0.009). Conclusions: The use of topical dexamethasone 0.1%/povidone-iodine 0.4% eye drops four times daily appears to reduce the duration of conjunctivitis, although it causes more stinging than artificial tears.


Transplantation Proceedings | 2013

Identification of Bacterial Infections and Clinical Manifestation Associated With Cytomegalovirus in Liver Transplantation Patients

Arlete Milan; A.M. Sampaio; A.C. Guardia; Célia Regina Pavan; Paula Durante Andrade; Sandra Helena Alves Bonon; Sandra Cecília Botelho Costa; E.C. Ataide; I.F.S.F. Boin; R.S.B. Stucchi

INTRODUCTION Liver transplantation has become the most effective therapy for the treatment of patients with end-stage liver disease. With new immunosuppressive agents the incidence of acute rejection has been significantly reduced, but infection has become a serious problem. OBJECTIVE Our objective was to correlate cytomegalovirus (CMV) positivity of antigenemia and polymerase chain reaction (PCR) with clinical manifestations and bacterial infections among patients undergoing liver transplantation. METHODS This prospective study included patients monitored for 6 months for early detection of CMV infection. Sample collections were performed at the time of surgery and weekly until the second month followed by fortnightly in the third month, and monthly in the fourth to sixth month. CMV infection was defined by positive antigenemia (>3 cells) or 2 positive PCR tests associated or not with clinical symptoms. The methodology for the diagnosis of bacterial infection was through biochemical tests and the automated VITEK/bioMérieux (identification and antibiogram) using samples of urine and blood cultures. Chi-square test was used for dicotomic variables with significant differences when P < .05. RESULTS Sixteen patients (32%) had CMV infections, including 13 (81%) with concomitant infections. Thirty-four patients (68%) did not have CMV infections and 8 of these (24%) had bacterial infection. There was a high correlation with bacterial infections among CMV-positive patients. CONCLUSION Bacterial infections after liver transplantation were associated with CMV infection.


Transplantation Proceedings | 2012

Co-infection and Clinical Impact of Human Herpesvirus 5 and 6 in Liver Transplantation

A.M. Sampaio; A.C. Guardia; Arlete Milan; A.N. Sasaki; Paula Durante Andrade; Sandra Helena Alves Bonon; R.S.B. Stucchi; S.C. Botelho Costa; I.F.S.F. Boin

BACKGROUND Human herpesvirus (HHV) 5 and 6 remain latent after primary infection and can be reactivated after immunosuppression for organ transplantation. An association between HHV-5 and HHV-6 has been reported in liver transplant patients. The coinfection is associated with clinical manifestations and graft dysfunction. OBJECTIVE The aim of this study was to monitor herpesviruses in liver transplant recipients to better understand issues involving coinfection with HHV-5/6 and correlations with acute cellular rejection episodes and bacterial infections. METHODS Forty-five adult liver transplant patients of median age 47 years (range, 18-66), gave blood samples and liver biopsies in the first 6 months after their surgeries. Viremia was detected with the use of nested PCR and antigenemia; the Banff classification was used to detect allograft rejection. RESULTS IgG positive for HHV-5 was observed in 94% of subjects whose main indication (67%) for transplantation was hepatitis C. Twenty-three (51.1%) displayed cytomeg virus (CMV) infections and 12 (26.7%) HHV-6 infection. There were 6 patients (13.3%) with HHV-5/6 coinfections. Eighteen of the 23 patients had CMV disease, showing a strong correlation between a positive test and CMV disease; 6 displayed an acute cellular rejection episode in the same period (χ(2) = 6.62; P < .03). Four out of 6 patients who displayed coinfections (HHV-5/6) had concomitant bacterial infections; 3/6 experienced graft rejection episodes. During follow-up, 1 patient had HHV-6 infection diagnosed as encephalitis followed by fever on the 24th day after surgery. The median 32 days for HHV-6 detection by nested PCR positivity was shorter than 38 days for HHV-5. CONCLUSIONS HHV-5/6-infected patients displayed more allograft rejection episodes, coinfections, and concomitant bacterial infections, besides an higher risk for CMV disease.


Transplant Infectious Disease | 2009

Human herpesvirus-7 in Brazilian liver transplant recipients: a follow-up comparison between molecular and immunological assays.

M.F. Peigo; R.L. Thomasini; A.L.P. Puglia; Sandra Cecília Botelho Costa; Sandra Helena Alves Bonon; I.F.S.F. Boin; M.I. Leonardi; N.G.S. Mota

Abstract: Human herpesvirus‐6 and ‐7 (HHV‐6, HHV‐7) remain latent after primary infection and can reactivate after transplantation. HHV‐6 active infection has been related to some clinical manifestation, but the role of HHV‐7 remains unclear. The clinical significance of HHV‐7 DNAemia is not completely known and the immune response against HHV‐7 has been poorly studied in transplantation. In this study, we investigated HHV‐7 DNAemia in liver transplant recipients and evaluated the immunoglobulin (Ig) G and IgM response against HHV‐7. A total of 22 adult liver transplant recipients were followed up for 90 days. HHV‐7 DNAemia was detected by nested polymerase chain reaction (PCR) in DNA extracted from sera. IgG and IgM detection was performed by immunofluorescent assay using HHV‐7‐infected cord blood mononuclear cells. A significant virus antibody response was defined as either a positive IgM or a ≥4‐fold rise in the virus IgG antibody. All patients had pre‐transplant HHV‐7‐positive serostatus. Nine of 22 (40.9%) patients presented HHV‐7 DNAemia during follow‐up. All these patients had anti‐HHV‐7‐positive IgM and/or significant increase in IgG titers with concurrent or subsequent DNAemia. In patients without DNAemia and low persistent IgG antibody titers, IgM was not detected. Correlation between nested PCR and IgM detection was statistically significant (P=0.01). Our study indicates that nested PCR in DNA extraction from serum can be useful to detect and monitor HHV‐7 active infection in liver transplant recipients. IgM antibody detection also can be useful as a first immunological technique to detect active infection, especially if combined with PCR.


Revista Do Instituto De Medicina Tropical De Sao Paulo | 2003

Evaluation of an in-house specific immunoglobulin G (IgG) avidity ELISA for distinguishing recent primary from long-term human cytomegalovirus (HCMV) infection

Silmara Rodrigues de Souza; Sandra Helena Alves Bonon; Sandra Cecília Botelho Costa; Cláudio Lúcio Rossi

This article describes the standardization and evaluation of an in-house specific IgG avidity ELISA for distinguishing recent primary from long-term human cytomegalovirus (HCMV) infection. The test was standardized with the commercial kit ETI-CYTOK G Plus (Sorin Biomedica, Italy) using 8 M urea in phosphate-buffered saline to dissociate low-avidity antibodies after the antigen-antibody interaction. The performance of the in-house assay was compared to that of the commercial automated VIDAS CMV IgG avidity test (bioM rieux, France). Forty-nine sera, 24 from patients with a recent primary HCMV infection and 25 from patients with a long-term HCMV infection and a sustained persistence of specific IgM antibodies, were tested. Similar results were obtained with the two avidity methods. All 24 sera from patients with recently acquired infection had avidity indices compatible with acute HCMV infection by the VIDAS method, whereas with the in-house method, one serum sample had an equivocal result. In the 25 sera from patients with long-term infection, identical results were obtained with the two methods, with only one serum sample having an incompatible value. These findings suggest that our in-house avidity test could be a potentially useful tool for the immunodiagnosis of HCMV infection.


Revista Do Instituto De Medicina Tropical De Sao Paulo | 2006

Comparison of serology, antigenemia assay and the polymerase chain reaction for monitoring active cytomegalovirus infections in hematopoietic stem cell transplantation patients

Sandra Helena Alves Bonon; Cláudio Lúcio Rossi; Carmino Antonio de Souza; Afonso Celso Vigorito; Sandra Cecília Botelho Costa

Forty-six allogeneic hematopoietic stem cell transplantation (HSCT) patients were monitored for the presence of CMV antibodies, CMV-DNA and CMV antigens after transplantation. Immunoenzymatic serological tests were used to detect IgM and the increase in CMV IgG antibodies (increase IgG), a nested polymerase chain reaction (N-PCR) was used to detect CMV-DNA, and an antigenemia assay (AGM) was used to detect CMV antigens. The presence of CMV-IgM and/or CMV-increase IgG antibodies was detected in 12/46 (26.1%) patients, with a median time between HSCT and the detection of positive serology of 81.5 days. A positive AGM was detected in 24/46 (52.2%) patients, with a median time between HSCT and antigen detection of 62 days. Two or more consecutive positive N-PCR results were detected in 32/46 (69.5%) patients, with a median time between HSCT and the first positive PCR of 50.5 days. These results confirmed that AGM and mainly PCR are superior to serology for the early diagnosis of CMV infection. Six patients had CMV-IgM and/or CMV-increase IgG with a negative AGM (five cases) or N-PCR assay (one case). In five of these cases the serological markers were detected during the first 100 days after HSCT, the period of highest risk. These findings support the idea that serology may be useful for monitoring CMV infections in HSCT patients, especially when PCR is unavailable.


Brazilian Journal of Microbiology | 2010

ACTIVE HUMAN CYTOMEGALOVIRUS INFECTION AND GLYCOPROTEIN B GENOTYPES IN BRAZILIAN PEDIATRIC RENAL OR HEMATOPOIETIC STEM CELL TRANSPLANTATION PATIENTS

Débora de Campos Dieamant; Sandra Helena Alves Bonon; Liliane Cury Prates; Vera Maria Santoro Belangelo; Erika R. Pontes; Sandra Cecília Botelho Costa

A prospective analysis of active Human Cytomegalovirus infection (HCMV) was conducted on 33 pediatric renal or hematopoietic stem cell post-transplant patients. The HCMV-DNA positive samples were evaluated for the prevalence of different gB subtypes and their subsequent correlation with clinical signs. The surveillance of HCMV active infection was based on the monitoring of antigenemia (AGM) and on a nested polymerase chain reaction (N-PCR) for the detection of HCMV in the patients studied. Using restriction analysis of the gB gene sequence by PCR-RFLP (Restriction Fragment Length Polymorphism), different HCMV strains could be detected and classified in at least four HCMV genotypes. Thirty-three pediatric recipients of renal or bone marrow transplantation were monitored. Twenty out of thirty-three (60.6%) patients demonstrated active HCMV infection. gB1 and gB2 genotypes were more frequent in this population. In this study, we observed that gB2 had correlation with reactivation of HCMV infection and that patients with mixture of genotypes did not show any symptoms of HCMV disease. Future studies has been made to confirm this.

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I.F.S.F. Boin

State University of Campinas

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A.M. Sampaio

State University of Campinas

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R.S.B. Stucchi

State University of Campinas

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A.C. Guardia

State University of Campinas

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