MARIA ELIZABETE MENDES
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
18 resultados
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- 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.
- Point-of-Care Testing: General Aspects(2018) FERREIRA, Carlos E. S.; GUERRA, Joao C. C.; SLHESSARENKO, Natasha; SCARTEZINI, Marileia; FRANCA, Carolina N.; COLOMBINI, Marjorie P.; BERLITZ, Fernando; MACHADO, Antonia M. O.; CAMPANA, Gustavo A.; FAULHABER, Adriana C. L.; GALORO, Cesar A.; DIAS, Claudia M.; SHCOLNIK, Wilson; MARTINO, Marines D. V.; CESAR, Katia R.; SUMITA, Nairo M.; MENDES, Maria E.; FAULHABER, Marcelo H. W.; PINHO, Joao R. R.; BARBOSA, Ismar V.; BATISTA, Marcelo C.; KHAWALI, Cristina; PARIZ, Vitor M.; ANDRIOLO, AdagmarPoint-of-Care Testing (POCT) has been highlighted in the health care sector in recent decades. On the other hand, due to its low demand, POCT is at a disadvantage compared to conventional equipment, since its cost is inversely proportional to the volume of use. In addition, for the implementation of POCT to succeed, it is essential to rely on the work of a multidisciplinary team. The awareness of health professionals of the importance of each step is perhaps the critical success factor. The trend towards the continuous advancement of the use of POCT and the great potential of its contributions reinforce the need to implement quality management tools, including performance indicators, to ensure their results. This review presents some advantages and disadvantages concerning POCT and the real need to use it. A worldwide call for the availability of easy-to-use health technologies that are increasingly closer to the final user is one of the main reasons for this focus.
- 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.
article Pharmacokinetics of 6-thioguanine nucleotide and 6-methyl-mercaptopurine in a case of inadvertent combination therapy of azathioprine with allopurinol(2012) PACHECO-NETO, Maurílio; ALVES, Atecla N. L; FORTINI, Alexandre S.; SUMITA, Nairo M.; MENDES, Maria E.; TORRES, Larissa H. L.; DULEY, John A.; NAHAS, William C.; CHOCAIR, Pedro R.Background: Allopurinol was invented originally to improve response to thiopurine drugs, such as azathioprine (AZA) and mercaptopurine, but if they are given in combination then the thiopurine dose must be drastically reduced to about one third of a normal dose. Failure to reduce the thiopurine dose can cause severe toxicity, and has resulted in allopurinol usually being contraindicated for patients taking thiopurines. Case report: We present a case of a 44 year old female patient who received a renal transplant in 2001, with mycophenylate/tacrolimus/prednisolone immunosuppression. In 2004 the patient experienced gout symptoms and was prescribed 100 mg allopurinol per day. In 2008, her mycophenylate was replaced with 150 mg AZA. Within four weeks the patient was hospitalized suffering from severe myelotoxicity, with high blood levels of the AZA metabolite thioguanine nucleotide (6-TGN). AZA was stopped, with recovery of hematological parameters and elimination of AZA metabolites requiring a further two weeks. Discussion: This case demonstrates the risk of rapid-onset myelotoxicity due to AZA/ allopurinol co-therapy without correct dose adjustment of these drugs. The availability of routine analysis of AZA metabolites was useful for rapidly diagnosing the cause of the toxicity and monitoring recovery. Interestingly, the half-life of AZA metabolites after cessation of therapy (5.5 days for 6-TGN, 4 days for 6-MMP) was comparable to values in the absence of allopurinol: this excluded the elevation of 6-TGN being caused by an increased half-life.- Validation protocol for multiple blood gas analyzers in accordance with laboratory accreditation programs(2015) EBNER, Pérsio A. R.; ROMANO, Paschoalina; SANT’ANNA, Alexandre; MENDES, Maria Elizabete; OLIVEIRA, Magna; SUMITA, Nairo M.Introduction: The results of blood gas analysis using different instrumentation can vary widely due to the methodological differences, the calibration procedures and the use of different configurations for each type of instrument. Objective: The objective of this study was to evaluate multiple analytical systems for measurement of blood gases, electrolytes and metabolites in accordance with the accreditation program (PALC) of Sociedade Brasileira de Patologia Clínica/Medicina Laboratorial (SBPC/ML). Materials and methods:20 samples were evaluated in three ABL800 Flex (Radiometer Medical ApS, Denmark) blood gas analyzers, and the results were compared with those of the device in use, which was considered the reference. The analysis of variance (Anova) was applied for statistical purposes, as well as the calculation of mean, standard deviation and coefficient of variation.Results:The p values obtained in the statistical analysis were: pH = 0.983, pO2 = 0.991, pCO2 = 0.353, lactate = 0.584, glucose = 0.995, ionized calcium = 0.983, sodium = 0.991, potassium = 0.926, chlorine = 0.029. Conclusion: The evaluation of multiple analytical systems is an essential procedure in the clinical laboratory for quality assurance and accuracy of the results.
- The critical value concept in clinical laboratory(2016) ROCHA, Bruna Cláudia B.; ALVES, José Adilson R.; PINTO, Félix Pedro D.; MENDES, Maria Elizabete; SUMITA, Nairo M.ABSTRACT The critical value is a laboratory result representing a pathophysiological state that offers risk to a patient's life. The communication of these results is a laboratory responsibility and, according to the literature, 95% of physicians consider it useful in decision-making and patient management. Two-thirds of critical results lead to some change in therapeutic approach. The communication of critical results is a requirement for laboratory accreditation programs. Thus laboratories should establish a list of tests, their critical values, and the procedure describing the communication flow. The performance indicator for this activity should consider the time between results release and their effective communication, and the percentage of successful communication. There is no standardization of laboratory parameters that need to have critical values established, not even the ranges to be considered for notification purposes. The frequent update of test lists and critical value ranges based on literature reviews and on experience exchange among clinical laboratories ensure the continuous improvement process for this procedure and patient safety.
- Clinical Applications of Point-of-Care Testing in Different Conditions(2018) SUMITA, Nairo M.; FERREIRA, Carlos E. S.; MARTINO, Marines D. V.; FRANCA, Carolina N.; FAULHABER, Adriana C. L.; SCARTEZINI, Marileia; PINHO, Joao R. R.; DIAS, Claudia M.; CESAR, Katia R.; PARIZ, Vitor M.; GUERRA, Joao C. C.; BARBOSA, Ismar V.; FAULHABER, Marcelo H. W.; BATISTA, Marcelo C.; ANDRIOLO, Adagmar; MENDES, Maria E.; MACHADO, Antonia M. O.; COLOMBINI, Marjorie P.; SLHESSARENKO, Natasha; SHCOLNIK, Wilson; KHAWALI, Cristina; CAMPANA, Gustavo A.; BERLITZ, Fernando; GALORO, Cesar A.Background: The use of point-of-care testing (POCT) in different clinical applications is justified by the fact that the time to release the result is shortened, allowing the physician to define the diagnosis and most appropriate therapy in a shorter time. However, the negative aspects must also be highlighted and studied so that we can move forward with the use of these devices. These negative aspects include greater analytical imprecision compared to laboratory automation, the variability between different equipment from different manufacturers, the risk of inappropriate use, a low level of global regulation, higher costs compared with laboratory testing and cost ineffectiveness in terms of health care. Methods and Results: This review presents some clinical applications of POCT in different scenarios, such as for diabetes mellitus, infectious diseases, pediatrics, and chronic kidney disease, among others. Conclusions: We hope to see a global consensus on an acceptable quality standard for performing POCT that is adaptable, practical, and cost effective in primary care settings, ensuring patient safety, and minimizing the risk of harm.
article A case report of azathioprine-induced recurrent acute pancreatitis associated with high levels of 6-thioguanine nucleotides in a renal transplant recipient(2012) PACHECO-NETO, Maurílio; ALVES, Atecla N. L; FORTINI, Alexandre S.; SUMITA, Nairo M.; MENDES, Maria E.; TORRES, Larissa H. L.; DULEY, John A.; NAHAS, William C.; CHOCAIR, Pedro R.Background: Myelotoxicity is the most common side effect associated with the use of azathioprine (AZA) in transplant recipients, while other side effects – rash, nausea, flu-like symptoms, diarrhea, hepatitis, and pancreatitis – are relatively rare. This is the first report of the evolution in a kidney transplant recipient of recurrent acute pancreatitis related to the use of AZA and high levels of 6-thioguanine nucleotide (6-TGN). Case report: A 57-year-old Brazilian male renal transplant patient remained stable for 30 years on a maintenance immunosuppressive regimen of AZA and prednisone. The patient experienced three episodes of mild acute pancreatitis in 2004, 2007 and 2008, and despite intensive investigation, AZA was not suspected as the causal agent of pancreatitis. In October 2008 the patient was found to have raised levels of erythrocyte 6-TGN, which resolved rapidly when AZA was interrupted. His maintenance immunosuppression regimen was subsequently changed to mycophenolate mofetil/ tacrolimus/ prednisone. Discussion: Despite the classic pharmacogenetic model for thiopurines afforded by thiopurine methyltransferase (TPMT) and highly variable pharmacokinetics, AZA continues to be used empirically, i.e. mg/kg. In transplant recipients, AZA is usually employed as part of polytherapy, which complicates the elucidation of the cause of drug-related side effects. We propose that therapeutic drug monitoring of AZA metabolites is useful for differential diagnosis of the causes of drug-related side effects, such as acute pancreatitis.- Practical aspects of the use of FMEA tool in clinical laboratory risk management(2013) MENDES, Maria Elizabete; EBNER, Pérsio de Almeida Rezende; ROMANO, Paschoalina; PACHECO NETO, Maurílio; SANT’ANNA, Alexandre; SUMITA, Nairo MassakazuINTRODUCTION: This paper presents the failure modes and effects analysis (FMEA) tool in a clinical laboratory through the introduction of new technology for blood gas and serum ionized calcium in multi-parameter analyzers such as Point of Care Testing (POCT). OBJECTIVE: To present FMEA as a tool for risk managing and improvement with the introduction of new technologies in a public laboratory. METHODS: The change of multiparameter gas analyzer type POCT was defined and described as a process. Subsequently, the criteria were presented to the risk assessment and its quantification. We studied the failure modes that might occur in this process. We established three action plans involving improvements to be made in the technological change. FMEA was applied in two stages: at the beginning of the project and after the implementation of the proposed measures. RESULTS: The first plan involved administrative measures related to the bidding process; the second preventive action involved the possibility of which supplier would win the bid by studying the efficiency of the analyzer and its impact on productivity; the third set of actions was directed to improvements in the relationship with the clinical staff in order to minimize occasional complaints. The last actions referred to employing new employees to meet the growing demand. CONCLUSION: FMEA proved to be a reliable tool for performance improvement, which proactively identifies, prioritizes and mitigates patient risks.
article Azathioprine-related severe diarrhea induced by high levels of 6-thioguanine nucleotides in renal transplant recipient carrying mutant thiopurine methyltransferase: a case report(2012) PACHECO-NETO, Maurílio; NASSER, Paulo D.; ALVES, Atecla N. L; FORTINI, Alexandre S.; SUMITA, Nairo M.; MENDES, Maria E.; ONO-NITA, Suzane K.; CANÇADO, Eduardo L. R.; TORRES, Larissa H. L.; DULEY, John A.; NAHAS, William C.; CHOCAIR, Pedro R.Introduction: Azathioprine (AZA) is widely used to prevent rejection in organ transplants and treat auto-immune diseases. The major side effects reported for the use of AZA are myelotoxicity, hepatotoxicity, and flu-like symptoms, while there are a few reports of severe diarrhea. Thiopurine methyltransferase (TPMT) is a major catabolic route that has pharmacogenetic importance. We describe here the evolution of a renal transplant recipient carrying a mutant TPMT allele, who developed severe diarrhea related to the use of AZA and high levels of 6-TGN. Case presentation: A 28-year-old Brazilian Caucasian man underwent preemptive renal transplant in 2006 and presented persistent diarrhea. Therapeutic drug monitoring (TDM) of AZA metabolites indicated high levels of red blood cell 6-TGN, and AZA was discontinued in view of the patient’s persistent diarrhea. Normalization of bowel habit was gradual, parallel to the patient’s physical condition. TPMT genotype showed the mutant allele TPMT*1/*3A, genotype associated with low enzymatic activity, high levels of 6-TGN and consequently high susceptibility to side effects. Discussion: AZA has been empirically used for about 50 years, even though the pharmacokinetics is demonstrably variable among individuals. It is known that AZA has a higher selectivity for rapidly multiplying cells, which also implies higher toxicity. So it can be inferred that the high levels of 6-TGN were causing damage to the patient’s intestinal mucosa. This report shows that TDM of AZA may be useful for differential diagnosis of the cause of less frequent adverse events, such as diarrhea.