FABIANA AGENA
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
74 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 74
- UPLC-MS/MS assay validation for tacrolimus quantitative determination in peripheral blood T CD4+and B CD19+lymphocytes(2018) ROMANO, Paschoalina; FERNANDES, Maria da Luz; EBNER, Persio de Almeida Rezende; OLIVEIRA, Nayara Duarte de; OKUDA, Larissa Mitsue; AGENA, Fabiana; MENDES, Maria Elizabete; SUMITA, Nairo Massakazu; COELHO, Veronica; DAVID-NETO, Elias; GALANTE, Nelson ZocolerMonitoring tacrolimus (Tac) exposure in cell matrices enriched with lymphocytes can improve Tac therapeutic drug monitoring (TDM) in solid organ transplant recipients. An UPLC-MS/MS based assay for Tac quantification in peripheral blood T CD4+ and B CD19+ lymphocytes was developed. Peripheral blood mononuclear cells (PBMC) were obtained by density gradient centrifugation and highly purified (purity >90%) T CD4+ and B CD19+ cell suspensions were acquired by magnetic negative selection from whole blood of 6 healthy volunteers. The purity of lymphocyte suspensions was checked by flow cytometry. Tac extraction was performed in a liquid-liquid zinc sulfate, methanol and acetonitrile based medium. Ascomycin was used as internal standard. The equipment used was a Waters (R) Acquity (TM) UPLC system (Waters Corporation, Milford, MA, USA). The chromatographic run was performed on a Waters (R) MassTrak TDM C18 (2.1 x 10 mm) column (Waters Corporation, Milford, MA, USA). at a flow rate of 0.4 mL/min. The instrument was set in electrospray positive ionization mode. The method was validated according to Clinical Laboratory Standard Institute (CLSI) guidelines and showed a high sensitivity and specificity over a range of 0-5.2 ng/mL in PBMC, 0-5.0 ng/mL in T CD4+ Lymphocytes and 0-5.3 ng/mL in B CD19+ lymphocytes. Precision was appropriate with CV of intra-assay quantifications ranging from 4.9 to 7.4%, and of inter-assay quantifications from 7.2 to 13.9%. Limit of detection and quantification were 0.100 and 0.115 ng/mL in PBMC, 0.058 and 0.109 ng/mL in T CD4+ and 0.017 and 0.150 ng/mL in B CD19+ cells. Matrix effect was not significant among all the studied matrices. Samples showed stability for Tac quantification over a period of 90 days either at room temperature or at -30 degrees C storage conditions. The method was applied to clinical samples of 20 kidney transplant recipients. Concentrations ranged from 2.200 to 11.900 ng/mL in whole blood, from 0.005 to 0.570 ng/10(6) cells in PBMC, from 0.081 to 1.432 ng/10(6) cells in T CD4+, and from 0.197 to 1.564 ng/10(6) cells in B CD19+ cell matrices. The method has potential applicability for Tac TDM in solid organ transplant recipients.
conferenceObject EDUCATING FOR DONATION: A PROPOSAL FOR LIFE(2015) AGENA, Fabiana; LEAL, Moraes Edvaldo; RIBEIRO, Brescia Silvia; ANSELMO, Oliveira Neide; NASCIMENTO, Moraes Bianca; REDO, Celia Roseli Duarte; CORTEZI, Jeane Maria Silva; SILVA, Leonardo Borges Barros; NAHAS, William CarlosconferenceObject Bone and Mineral Metabolism and Fibroblast Growth Factor 23 Levels After Kidney Donation(2014) FERREIRA, G.; GUERRA, G.; SCHIAVENATO, E.; AGENA, F.; MOYSES, R.; DAVID-NETO, E.; WOLF, M.- The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study(2012) DAVID-NETO, Elias; SOUZA, Patricia Soares; PANAJOTOPOULOS, Nicolas; RODRIGUES, Helcio; VENTURA, Carlucci Gualberto; DAVID, Daisa Silva Ribeiro; LEMOS, Francine Brambate Carvalhinho; AGENA, Fabiana; NAHAS, William Carlos; KALIL, Jorge Elias; CASTRO, Maria Cristina RibeiroOBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short-and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T-and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (Luminex (R)), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed ""de novo'' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection, although survival rates are similar when patients transpose the first months after receiving the graft. Our data also suggest that early posttransplant donor-specific antibody monitoring should increase knowledge of antibody dynamics and their impact on long-term graft outcome.
conferenceObject Desensitization Using Only IVIG: Is That an Option for Highly-Sensitized Patients Waiting for Kidneys from Cadaveric Donors?(2019) PAIXAO, J. O.; ULISSES, L. R.; SOUZA, P. S.; BEZERRA, G.; AGENA, F.; RODRGUES, H. P.; PANAJOTOPOULOS, N.; PAULA, F. J.; DAVID-NETO, E.; CASTRO, M. R.- Seroconversion of 2009 pandemic influenza A (H1N1) vaccination in kidney transplant patients and the influence of different risk factors(2013) AZEVEDO, L. S.; GERHARD, J.; MIRAGLIA, J. L.; PRECIOSO, A. R.; TIMENETSKY, M. dC S. Tavares; AGENA, F.; GAMBA, C.; YASUDA, M. A. Shikanai; DAVID-NETO, E.; PIERROTTI, L.BackgroundInfluenza may present a high morbidity and mortality in solid organ transplanted patients (SOTP). Annual influenza virus vaccine is recommended for SOTP. However, low levels of seroconversion in SOTP have been reported. The aim of this study was to evaluate the immunogenicity of 2009 pandemic influenza A (H1N1) - A(H1N1)pdm09 - vaccine in kidney transplant patients and to analyze which features might affect seroconversion. MethodsThis study was conducted from March to August 2010 at the Renal Transplantation Unit of University of SAo Paulo, Brazil. A total of 85 renal transplant patients attending the outpatient unit received one 15-g intramuscular dose of A(H1N1)pdm09 influenza vaccine (reassortant vaccine virus A/California/7/2009 [NYMC X-179A]). Blood samples were collected immediately before and 21days after the vaccine was given. Antibody response was measured by the standard hemagglutination-inhibition (HI) assay. The primary immunogenicity endpoint for this study was seroconversion in previously seronegative patients (HI titers <1:40), and the secondary endpoint was the identification of features that could affect seroconversion in this population. ResultsFive (5.9%) patients presented HI titers prevaccination 1:40 and were excluded from further analysis. Seroconversion in previously negative patients occurred in 27 (34%) of 80 patients. Prevaccination HI titers geometrical mean was 5.8 and postvaccination 19.6 (ratio 3.4). Significant seroconversion rate factors were female gender, non-Caucasian ethnicity, and post-transplant time before vaccination. No impact was seen on seroconversion for age, donor type, tacrolimus and cyclosporine blood levels, renal function, or blood lymphocyte counts. Mycophenolate (MPA) showed a lower rate of seroconversion when compared with azathioprine. Tacrolimus and cyclosporine had similar seroconversion rates. Sirolimus use was associated with the highest rate of seroconversion, although these patient numbers were low. Immunosuppresssion containing MPA was considerably less effective in seroconversion than drug combinations with no MPA. Patients receiving sirolimus had more chance of seroconversion. HI titers geometric means pre/post vaccine were as follows: MPA (n=56): 5.8/12.8; tacrolimus (n=50): 5.9/16.2; cyclosporine (n=18): 5.4/24.2; azathioprine (n=19): 6.2/51.6; and sirolimus (n=6): 8/80. By univariate analysis, being female and non-White were variables associated with 3.3 times more chance of seroconversion than being male and White. In the multivariate analysis, the variables remaining in the model showed similar hazard ratios. ConclusionsIn this study, the monovalent A(H1N1)pdm09 influenza vaccine demonstrated low rates of seroconversion, particularly in patients on MPA, but with potentially higher response rates in patients on sirolimus.
- Cytomegalovirus prophylaxis in seropositive renal transplant recipients receiving thymoglobulin induction therapy: Outcome and risk factors for late CMV disease(2018) JR, Jose O. Reusing; FEITOSA, Emanoela B.; AGENA, Fabiana; PIERROTTI, Ligia C.; AZEVEDO, Luiz S. F.; KOTTON, Camille N.; DAVID-NETO, EliasBackgroundAnti-thymocyte globulin (ATG) therapy is a risk factor for cytomegalovirus (CMV) disease in renal transplant (RTx) recipients and therefore antiviral prophylaxis is commonly used. We evaluated the outcome of our current policy of 90days of CMV prophylaxis in seropositive recipients given ATG and the risk factors for the occurrence of CMV disease after prophylaxis. MethodsWe studied a retrospective cohort of 423 RTx (2010-2014) CMV-seropositive adults given ATG induction therapy. Results54 (13%) patients developed CMV disease at a median of 163days after transplant, of which 29 (54%) had viral syndrome and 25 (46%) had invasive disease. Median prophylaxis time (94days) and immunosuppressive drugs were similar between groups (CMV vs no-CMV). Those with CMV disease had more deceased donors and higher donor age, lower lymphocyte count, and lower median eGFR at day 90. Multivariable logistic regression analysis at day 90 and 180 found that eGFR 40ml/min/1.73m(2) (but not acute rejection) was associated with late CMV disease. In a separate validation cohort of 124 patients with 8% late CMV disease, eGFR 45 and lymphocyte count 800cells/mm(3) at the end of prophylaxis remained predictive of late CMV disease occurrence. ConclusionsThese data indicate that antiviral prophylaxis adequately prevented CMV in seropositive recipients given ATG, but late disease still occurred. Low eGFR and low lymphocyte count at the end of prophylaxis may help identify patients at higher risk of CMV disease.
- Prioritization Due to Dialysis Access Failure Impacts on Patient Survival after Kidney Transplantation(2013) REUSING JR., J.; SOUZA, P.; GALANTE, N.; AGENA, F.; PAULA, F. de; NAHAS, W.; DAVID-NETO, E.Dialysis vascular access failure, recipient of a non-renal solid organ transplantation and previous kidney donation are current indications of priority allocation (PA) for kidney transplant (KT) at our centre. Mortality among PA patients under dialysis is high and risk factors for long-term patient outcomes after transplantation remain largely elusive. In this study we analyzed a cohort of patients that received KT from Jan/2007 to Dec/2011. Long-term patient survival was compared between PA and non PA recipients transplanted in this period of time and clinical relevant data were analyzed. Data were recorded as of Aug/2012. Results: 948 KT were performed at our institution and 93 (9.8%) were included in our PA program. Most PA patients (n=86) had access failure. The mean follow up time was 32 (0 – 69) months. 5-year patient survival was lower in PA patients (76vs 86%, p=0.001). Twenty (21.5%) PA patients died and all deaths occurred in those with access failure, being 70% of them in the first 3 months. Causes of death were infection in 10 patients, bleeding complications (n=6), uremia (n=1), mesenteric ischemia (n=1) and unspecified shock (n=2). Considering this high mortality rate in the first 3 months after transplantation, we compared patients who died in this period of time (group A) vs. those who survived more than 3 months (group B). Age, gender, previous kidney transplants, sensitization, number of HLA mismatches, pre-transplant DSA, pre-transplant diabetes, induction therapy, DGF, rejection, use of heparin, IVIg and time from inscription in the PA program to transplantation were not statistically different between groups. Among 47 patients who were screened for thrombophilia, 83.3% from group A were positive vs. 31.7% from group B (p=0.01). Infection after transplantation and hemorrhagic complications were more frequent in group A. Groups were not different regarding causes of death. PA patients have a lower survival and this excessive death rate occur in the first three months after transplantation mainly due to infections and bleeding. Thrombophilia is very frequent in PA patients with HR....... for death.
conferenceObject A Critical Analysis of Equations for MPA Exposure in Patients Under EC-MPS and Tacrolimus(2017) DAVID-NETO, E.; TRIBONI, A.; RAMOS, F.; AGENA, F.; ROMANO, P.; FREITAS, G.- Diminished Mycophenolic Acid Exposure Caused by Omeprazole May Be Clinically Relevant in the First Week Posttransplantation(2012) DAVID-NETO, Elias; TAKAKI, Kelly M.; AGENA, Fabiana; ROMANO, Paschoalina; SUMITA, Nairo M.; MENDES, Maria E.; NERI, Leticia Aparecida Lopes; NAHAS, William C.Background: Some studies have reported a decreased absorption of mycophenolic acid (MPA) from mycophenolate mofetil (MMF) in renal transplanted (RTx) patients under proton-pump inhibitors (PPIs). There is still a lack of information regarding (1) whether this effect occurs when MMF is administered with either tacrolimus or cyclosporine A [calcineurin inhibitors (CNIs)], (2) whether the effect has the same amplitude during the first year after RTx, and finally (3) whether this decrease in exposure is clinically relevant. Methods: We retrospectively analyzed the omeprazole effect in 348 12-hour pharmacokinetic samplings [area under the curve (AUC) 0-12h] performed on days 7, 14, 30, 60, 180, and 360 after RTx in 77 patients who participated in previous trials. Results: For all periods, the groups with and without PPI did not differ in all variables. By mixed-model analysis of variance, PPI reduced the MPA AUC(0-12h) (P < 0.0008) in the patients under both CNIs mainly due to decreased absorption (P = 0.049). In the tacrolimus group, a lower exposure seemed also due to a decreased MPA reabsorption at 10-12 hours. The PPI effect remains throughout the first year but was clinically more important on day 7. By Cox analysis, the use of PPI was associated with a 25% less chance of being adequately exposed to MPA (95% confidence interval 0.58-0.99, P = 0.04). Similarly, the number of patients underexposed to MPA (AUC < 30 ng.h/mL) was higher at most periods in the PPI group but again not statistically significant. Conclusions: These data indicate that PPI decreases the MPA exposure when associated with both CNIs but particularly in the first week after RTx. In this period, the MMF dose should be increased. This effect lasts throughout the first year but does not seem to be clinically relevant after the first week.