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1.
Transplant Proc ; 47(1): 54-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25645769

RESUMO

The response mediated by B lymphocytes has a crucial impact on kidney transplantation due to the role of anti-human leukocyte antigen antibodies in rejection and the contradictory observation of high B-lymphocyte numbers in tolerant kidney transplant recipients. The basis of the contradiction could lay in the different function of B-cell subsets depending on their degree of differentiation. We ought to measure circulating B-lymphocyte percentages in patients with end-stage renal disease before kidney transplantation to identify those with a high risk of acute rejection. Eighty patients on the waiting list for kidney transplantation followed up in our center were recruited from 2010, and samples were taken just before kidney transplantation. Eleven of 80 patients presented an episode of acute rejection (13.75%) and had an increased frequency of switched (SW) B cells compared with the rejection-free group (median [interquartile range] 24.5% [18.6% to 39.6%] vs 15.1 [8.45% to 23.4%]; P = .025). Subsequently, the frequency of SW B cells was assessed as a predicting factor of acute rejection. A value higher than 18.4% predicted patients at risk of suffering an acute rejection episode with a sensitivity of 81.8% and a specificity of 60.9% and an area under the curve of 71.2%. Moreover, a decrease in naïve B-cell subsets was related to patients at risk of acute rejection. The percentage of circulating B-cell subsets before kidney transplantation could be used as biomarker of risk to suffer acute rejection. These unicenter data must be validated in multicenter studies.


Assuntos
Subpopulações de Linfócitos B , Rejeição de Enxerto/sangue , Rejeição de Enxerto/epidemiologia , Falência Renal Crônica/sangue , Falência Renal Crônica/cirurgia , Transplante de Rim , Biomarcadores/sangue , Humanos , Contagem de Linfócitos , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Fatores de Risco
2.
Transplant Proc ; 47(1): 76-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25645775

RESUMO

High blood pressure (BP) affects up to 90% of kidney transplant recipients and is associated with lower patient and graft survival rates. Kidney Disease/Improving Global Outcomes (KDIGO) guidelines suggest maintaining BP at lower than 130/80 mm Hg. Multidrug therapy is usually required for the control of BP in this population. Our aim was to analyze the number of antihypertensive drugs used in our kidney transplantation population at 1 year after transplantation and their influence on graft and patient outcome. We included 411 deceased-donor kidney transplantation cases; data were obtained from a prospectively maintained institutional database. BP was measured at the outpatient clinic. Approximately 97 patients were not under antihypertensive therapy, whereas 130, 119, 52, and 13 received 1, 2, 3, or 4 antihypertensive drugs, respectively. The number of antihypertensive drugs was significantly related to lower patient survival rates independently of a previous diagnosis of hypertension and diabetes, recipient age and sex and renal function at 1-year. After multivariate linear regression analysis high body mass index, male gender of recipients, donor hypertension, previous acute rejection, and cyclosporine therapy were risk factors independently related to a higher number of antihypertensive drugs. To conclude, the number of antihypertensive drugs is an objective and easy-to-measure marker related to lower patient survival rates. Recipient body mass index, type of calcineurin inhibitor, and acute rejection are modifiable risk factors whose control can help to reduce the number of antihypertensive drugs needed to treat high BP in the kidney transplantation population.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Índice de Massa Corporal , Ciclosporina/uso terapêutico , Complicações do Diabetes/complicações , Seleção do Doador , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo
3.
Transplant Proc ; 44(9): 2538-41, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146447

RESUMO

INTRODUCTION: Regulatory T cells (Tregs) have gained an important role in mechanisms of tolerance and protection against the transplant rejection. However, only limited retrospective data have shown a relationship between peripheral blood Tregs and better long-term graft survival. The purpose of the present study was to investigate prospectively circulating Treg levels and their association with long-term graft survival. METHODS: Ninety kidney transplant recipients underwent measurement of Treg levels in peripheral blood before as well as at 6 months and 1 year posttransplantation. Receiver operating characteristic curves were applied to test the sensitivity and specificity of Treg levels to predict prognosis. RESULTS: Treg levels before transplantation correlated with those at 6 months and 12 months posttransplantation (P < .001 and P = .002, respectively). Patients who maintained high Treg levels (above 70th percentile) at both 6 and 12 months displayed better long-term graft survival at 4 and 5 years follow-up (P = .04 and P = .043 respectively). There was no effect on patient survival. CONCLUSION: Detection of high levels of peripheral blood Tregs was associated with better graft survival possibly using as a potential marker of prognosis.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Transplante de Rim/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Contagem de Linfócito CD4 , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
4.
Transplant Proc ; 44(9): 2555-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146452

RESUMO

Due to disparity between organ supply and demand, use of kidneys from suboptimal donors has become increasingly common. Several donor quality systems have been developed to identify kidneys with an increased risk for graft dysfunction and loss. The purpose of our study was to compare the utility of deceased donor score (DDS) and expanded criteria donor (ECD) status to predict kidney transplant outcomes in a single center. We analysed 280 deceased donor renal transplantation procedures, collecting data from the prospectively maintained institutional database. Kidney transplant outcome variable included delayed graft function, 1-year glomerular filtration rate (GFR1y), and death-censored graft loss (DCGL). Kidneys were obtained from marginal donors in 45.7% of transplant recipients by DDS and in 24.9% by ECD. DDS-defined marginal donors suffered delayed graft function (DGF) more frequently than nonmarginal donors (40.8% vs 25.0%; P = .006), whereas ECD did not develop DGF at a greater rate. GFR1Y was significantly worse among patients receiving kidneys from marginal donors: DDS 40.3 ± 12.9 vs 57.7 ± 19.4 mL/min/1.73 m(2) (P < .001) and ECD 39.4 ± 14.1 vs 53.8 ± 19.1 mL/min/1.73 m(2) (P < .0001). The most severe donor category defined by DDS (grade D) showed an independently worse death-censored graft survival hazard rate [HR] 2.661, 95% confidence interval [CI], 1.076-6.582; P = .034). DDS and ECD scoring systems are based on donor information available at the time of transplantation that predict 1-year graft function. Moreover in our center, DDS was better to predict DGF and death-censored graft survival than ECD.


Assuntos
Técnicas de Apoio para a Decisão , Seleção do Doador , Transplante de Rim , Doadores de Tecidos/provisão & distribuição , Adulto , Distribuição de Qui-Quadrado , Função Retardada do Enxerto/etiologia , Função Retardada do Enxerto/fisiopatologia , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Espanha , Fatores de Tempo , Obtenção de Tecidos e Órgãos , Resultado do Tratamento
5.
Transplant Proc ; 44(9): 2585-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146462

RESUMO

INTRODUCTION: New-onset diabetes after transplantation (NODAT), an important complication of renal transplantation leads to reduced graft function and increased patient morbidity and mortality. Because of its high incidence and immense impact on clinical outcomes, prevention of NODAT is highly desirable. Several modifiable and nonmodifiable risk factors for NODAT have been described. The aim of this study was to analyze the influence of various drugs on the development of NODAT during the first year. METHODS: A retrospective analysis was performed on 303 adult kidney transplant recipients free of previously known diabetes. NODAT was defined as a fasting plasma glucose level ≥ 126 mg/dL confirmed by repeat testing on a different day. We excluded patients with transiently elevated fasting plasma glucose during the first 3 months. RESULTS: NODAT was diagnosed in 37 recipients (12.2%). Univariate analysis identified several variables related to NODAT: recipient age (P < .001), body mass index (P < .001), donor age (P = .005), family history of diabetes (P < .001), statin use (P = .005), diuretic use (P = .040) and tacrolimus therapy (P = .029). After multivariate analysis, recipient age (relative risk [RR] = 1.060, 95% confidence interval [CI] 1.019- 1.102, P = .004), family history of diabetes (RR = 3.562, 95% CI 1.574-8.058, P = .002), smoking habit (RR 2.514, 95% CI 1.118-5.655, P = .026) and diuretic use (RR = 2.496, 95% CI 1.087-5.733, P = .031) were independently associated with NODAT development. CONCLUSIONS: In our population of kidney transplant recipients, the main nonmodifiable risk factors for NODAT were recipient age and a family history of diabetes. Diuretic use was a modifiable risk factor associated with the development of NODAT. To reduce NODAT incidence, it is necessary to consider not only immunosuppressive therapy, but also concomitant drugs such as diuretics.


Assuntos
Diabetes Mellitus/induzido quimicamente , Diuréticos/efeitos adversos , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , Tacrolimo/efeitos adversos , Adulto , Fatores Etários , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Distribuição de Qui-Quadrado , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia , Fatores de Tempo , Resultado do Tratamento
6.
Transplant Proc ; 44(9): 2601-2, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146468

RESUMO

Hypertension is common following renal transplantation, affecting up to 80% of transplant recipients. It is generally accepted that hypertension is associated with poor graft survival and reduced life expectancy, contributing to increased cardiovascular risk factors and mortality rates. The aim of the study was to compare the blood pressure (BP) control in kidney transplant patients through the use of ambulatory BP monitoring (ABMP) versus office BP measurements (oBP). A multicenter, cross-sectional, observational study was conducted in 30 nephrology/kidney transplant units. Eligible patients included hypertensive cadaveric kidney transplant recipients aged <70 years, with a functioning kidney for at least 1 year and with an estimated glomerular filtration ≥30 mL/min/1.73 m(2) and a serum creatinine < 2.5 mg/dL. Recorded data included demographic characteristics, oBP, and ABPM and labroatory investigations. The 868 patients showed a mean recipient age of was 53.2 ± 11.6 years and mean follow-up after transplantation, 5.5 ± 2.8 years. Mean systolic and diastolic oBP were 140.2 ± 18 and 80.4 ± 10 mm Hg, respectively. Seventy-six percent of patients had oBP higher than or equal to 130/80 mm Hg. Mean 24 hour ABPM were 131.5 ± 14 and 77.4 ± 8.7 mm Hg for systolic and diastolic BP, respectively. Using the ABPM, we observed that 36.5% of subjects were controlled (mean 24-hour BP < 130/85 mm Hg). The two methods (oBP and ABPM) showed significant agreement. After ABPM, 65% of patients diagnosed as true controlled hypertension were considered to have white-coat RH. In clinical practice ABPM may help for better adjustment of drugs for adequate BP control.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Hipertensão/diagnóstico , Transplante de Rim/efeitos adversos , Adulto , Idoso , Anti-Hipertensivos/uso terapêutico , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Creatinina/sangue , Estudos Transversais , Taxa de Filtração Glomerular , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Hipertensão/fisiopatologia , Pessoa de Meia-Idade , Visita a Consultório Médico , Valor Preditivo dos Testes , Espanha , Fatores de Tempo , Hipertensão do Jaleco Branco/diagnóstico , Hipertensão do Jaleco Branco/etiologia , Hipertensão do Jaleco Branco/fisiopatologia
7.
Am J Transplant ; 12(1): 240-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22026730

RESUMO

Renal failure persisting after renal transplant is known as delayed graft function (DGF). DGF predisposes the graft to acute rejection and increases the risk of graft loss. In 2010, Irish et al. developed a new model designed to predict DGF risk. This model was used to program a web-based DGF risk calculator, which can be accessed via http://www.transplantcalculator.com . The predictive performance of this score has not been tested in a different population. We analyzed 342 deceased-donor adult renal transplants performed in our hospital. Individual and population DGF risk was assessed using the web-based calculator. The area under the ROC curve to predict DGF was 0.710 (95% CI 0.653-0.767, p < 0.001). The "goodness-of-fit" test demonstrates that the DGF risk was well calibrated (p = 0.309). Graft survival was significantly better for patients with a lower DGF risk (5-year survival 71.1% vs. 60.1%, log rank p = 0.036). The model performed well with good discrimination ability and good calibration to predict DGF in a single transplant center. Using the web-based DGF calculator, we can predict the risk of developing DGF with a moderate to high degree of certainty only by using information available at the time of transplantation.


Assuntos
Sobrevivência de Enxerto , Internet , Humanos , Medição de Risco
8.
Transplant Proc ; 43(6): 2208-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21839235

RESUMO

Renal transplant recipients are at high risk of cardiovascular disease (CVD). New-onset diabetes mellitus after transplantation (NODAT) contributes to the risk of CVD, reducing graft and patient survival. To improve outcome of kidney transplant recipients, it is of great interest to identify those patients who will develop NODAT. The aim of our study was to explore the predictive value of fifth-day fasting plasma glucose (FPG), third-month proteinuria, and pulse pressure (PP) for NODAT development. We analyzed 282 non-previously-diabetic kidney transplants in our center. Fifth-day FPG, PP, and third-month 24-hour proteinuria were collected. NODAT was defined at month 12 according to the "consensus guidelines": symptoms of diabetes plus casual glucose concentrations ≥ 200 mg/dL or FPG ≥ 126 mg/dL. Some 46 patients (16.3%) developed NODAT at month 12. Fifth-day FPG (133 ± 35 vs 108 ± 16 mg/dL, P < .001) and PP (57 ± 17 vs 49 ± 15 mm Hg, P = .007) were significantly higher in patients at risk for NODAT, but there was no difference in third-month proteinuria (652 ± 959 vs 472 ± 1336 mg, P = .390). A multivariate regression model showed an increased risk for NODAT associated with recipient age, body mass index, smoking habit, and a fifth-day FPG ≥ 126 mg/dL (relative risk 4.784, 95% confidence interval 2.121-10.788, P = .0002). The negative predictive value of a fifth-day FPG ≥ 126 mg/dL for predicting 1-year NODAT was 89.4%. Fifth-day FPG was independently related to NODAT development. The detection of a fifth-day FPG ≥ 126 mg/dL increases the risk of suffering NODAT more than 4 times. Fifth-day FPG < 126 mg/dL allows us to identify a transplant population with a low risk (near 10%) for NODAT.


Assuntos
Glicemia/metabolismo , Pressão Sanguínea , Diabetes Mellitus/etiologia , Jejum/sangue , Transplante de Rim/efeitos adversos , Proteinúria/etiologia , Adulto , Distribuição de Qui-Quadrado , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Espanha , Fatores de Tempo
9.
Nefrología (Madr.) ; 30(6): 687-697, nov.-dic. 2010. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-104637

RESUMO

Justificación: Se conoce como nefroesclerosis la enfermedad renal crónica (ERC) que complica la hipertensión arterial (HTA) esencial. La ausencia de correlación entre el control de la HTA y la progresión a ERC terminal sugiere la existencia de una enfermedad intrínseca y primitiva. Recientemente se ha asociado con polimorfismos del gen MYH9 en individuos afroamericanos. El objetivo del trabajo que presentamos es determinar si algún polimorfismo de dicho gen se relaciona en raza caucásica con la asociación de HTA esencial y nefroesclerosis y, además, conocer los marcadores de progresión a ERC terminal. Será un estudio retrospectivo que comparará a pacientes con nefroesclerosis frente a pacientes con HTA esencial sin enfermedad renal y, además, se incluirán pacientes con nefroesclerosis y progresión de la enfermedad renal frente a los que se mantienen estables. Métodos: Entre octubre de 2009 y octubre de 2010 se incluirán 500 pacientes con ERC (estadios 3-5) atribuida a nefroesclerosis según criterios clínicos habituales, y 300 pacientes afectados de HTA esencial (FGe >60ml/min/1,73 m2; microalbuminuria <300 mg/g). Para el estudio genético también se incluirán 200 controles sanos de población general. Habrá dos cortes del estudio, la primera visita en el hospital y la visita final (en estadio 5 el inicio del tratamiento sustitutivo constituirá el final del seguimiento). Se registrarán datos clínicos y analíticos, y se recogerán muestras de sangre para el estudio genético. Discusión: Nuestro estudio, con la doble vertiente genética y clínica, tratará de determinar si en la raza caucásica existe relación entre el diagnóstico de nefroesclerosis y el gen MYH9, y estudiará, además, los posibles marcadores de progresión (AU)


Background: Hypertensive nephrosclerosis is a chronic kidney disease (CKD) associated to essential hypertension. The lack of correlation between strict control of hypertension and progression of CKD suggests an intrinsic and primary disease. New evidence suggests that MYH9 gene alterations are associated with nephrosclerosis in African Americans. The aim of this study is to investigate whether a polymorphism of MYH9 in Caucasians is linked to the association of essential hypertension and nephrosclerosis. The secondary objective is to identify the clinical risk factors of progression to end-stage renal disease (ESRD). This is a retrospective study that will compare patients with nephrosclerosis versus essential hypertensives without renal disease, and also patients with nephrosclerosis and impaired rena l function versu s those that are stable .Methods: Between October 2009 and October 2010, 500patients stages 3-5 CKD attributed to nephrosclerosis according to usual clinical criteria, and 300 essential hypertensives (eGFR > 60 mL/min/1.73m2; mi c roalbuminur ia<300 mg/g) will be recruited. 200 healthy controls from general population will also be included for the genetic study. There will be two sections of the study, first and final visit to the clinic (stage 5, the start of replacement therapy will be the end of follow-up). Clinical and laboratory data will be recorded, and blood samples will be collected. Discussion: Our study will seek to determine if there exists a relationship between the diagnosis of nephrosclerosis and MYH9 gene in the Caucasian race, and to study possible risk factors for progression to ESRD, on both clinical and genetic basis (AU)


Assuntos
Humanos , Nefroesclerose/genética , Hipertensão/genética , Insuficiência Renal Crônica/fisiopatologia , Estudos de Associação Genética , Proteinúria/epidemiologia , Progressão da Doença
10.
Nefrologia ; 30(6): 687-97, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-21113220

RESUMO

BACKGROUND: Hypertensive nephrosclerosis is a chronic kidney disease (CKD) associated with essential hypertension. The lack of correlation between hypertension control and progression to end-stage CKD suggests an intrinsic and primitive disease. New evidence suggests that MYH9 gene alterations are associated with polymorphisms in African Americans. The aim of this study is to investigate whether a polymorphism of MYH9 in Caucasians is linked to essential hypertension and nephrosclerosis. The secondary objective is to identify the clinical risk factors of progression to end-stage CKD. This is a retrospective study that will compare patients with nephrosclerosis and essential hypertensives without renal disease, and also patients with nephrosclerosis and impaired renal function with those that are stable. METHOD: Between October 2009 and October 2010, 500 patients with stages 3-5 CKD attributed to nephrosclerosis according to usual clinical criteria, and 300 essential hypertensives (eGFR>60 mL/min/1.73 m2; microalbuminuria <300 mg/g) are to be recruited. A total of 200 healthy controls from the general population are also to be included for the genetic study. There are two study sections, being the first and final visits to the clinic (for stage 5 cases, the start of replacement therapy will be the end of follow-up). Clinical and laboratory data will be recorded, and blood samples will be collected. DISCUSSION: Our study will aim to determine if there is a relationship between the diagnosis of nephrosclerosis and the MYH9 gene in Caucasians, and to study possible risk factors for progression to end-stage CKD, on both clinical and genetic bases.


Assuntos
Hipertensão/genética , Proteínas Motores Moleculares/genética , Estudos Multicêntricos como Assunto/métodos , Cadeias Pesadas de Miosina/genética , Nefroesclerose/genética , Adulto , Idoso , Comorbidade , Progressão da Doença , Feminino , Predisposição Genética para Doença , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/etnologia , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/economia , Nefroesclerose/epidemiologia , Nefroesclerose/etnologia , Nefroesclerose/etiologia , Apoio à Pesquisa como Assunto , Estudos Retrospectivos , Fatores de Risco , Espanha/epidemiologia , População Branca/genética
11.
Transplant Proc ; 42(8): 2854-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970549

RESUMO

BACKGROUND: The cytokine interleukin-6 (IL-6) is important in both immune responses and cardiovascular diseases. The IL-6 promoter polymorphism -174 G/C is associated with increased plasma concentrations of IL-6. The relationship between IL-6 polymorphisms and graft survival, cardiovascular events, and new-onset diabetes mellitus after kidney transplantation is controversial. OBJECTIVE: To analyze whether IL-6 (-174 G/C) polymorphism influences kidney graft survival or development of chronic allograft nephropathy, cardiovascular events, or new- onset diabetes. METHODS: The IL-6 promoter polymorphism (-174 G/C) was analyzed using the polymerase chain reaction with sequence-specific primers in 335 kidney transplant recipients. Data for graft survival, chronic graft nephropathy, cardiovascular events, and new-onset diabetes were obtained retrospectively from clinical records. Categorical variables were compared between individuals with CC, GG, and GC genotypes using χ2 tests. Survival analysis was performed using the Kaplan-Meier method, comparing groups using the log-rank test. RESULTS: No significant differences were observed in 5-year graft survival between individuals with CC and GC/GG genotypes (85.3% vs 77.1%; P=.22). Nor were significant differences noted in the rates of chronic allograft nephropathy (37.5% vs 33.8%; P=.48), cardiovascular events (10.0% vs 23.0%; P=.10), or new-onset diabetes (7.5% vs 11.8%; P=.28). CONCLUSION: There is no association between IL-6 (-174 G/C) polymorphism and graft survival or development of chronic allograft nephropathy, cardiovascular events, or new- onset diabetes.


Assuntos
Sobrevivência de Enxerto , Interleucina-6/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Humanos
12.
Transplant Proc ; 42(8): 2861-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970552

RESUMO

Plasma cell dyscrasias can cause renal disease. Sensitive methods have recently been introduced to quantify serum free light chains (sFLCs). Renal function may influence the variability of these methods, as shown in chronic kidney disease (CKD) patients, but this problem has not been widely addressed in renal transplant patients. Herein, we examined the association between polyclonal sFLC concentrations and renal function among a population of renal transplant patients. We studied 102 kidney allograft recipients and 53 CKD patients classified according to KDOQI (Kidney Disease Outcomes Quality Initiative) stages. None of them had been diagnosed with monoclonal gammopathy. sFLCs were quantified by nephelometry. Both serum κ and λ free light chain concentrations rose progressively through each stage of KDOQI among both transplant and nontransplant patients (P<.0001). In the former setting, sFLC concentrations significantly correlated, using a Spearman coefficient, with serum creatinine, and serum cystatin concentrations as well as estimated glomerular filtration rate: namely, 0.723, 0.797, and -0.711 for sκFLC and 0.705, 0.759, and -0.694 for sλFLC, respectively (P<.0001 in all cases). Spearman correlation coefficients in nontransplant patients were: 0.559, 0.848, and -0.766 for sκFLC and 0.702, 0.875, and -0.855 for sλFLC, respectively (P<.0001 in all cases). In conclusion, sFLCs must be interpreted cautiously due to their clear association with renal function. Therefore, renal transplantation did not produce changes that were different from those dependent on renal function.


Assuntos
Cadeias Leves de Imunoglobulina/sangue , Transplante de Rim , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade
13.
Transplant Proc ; 42(8): 2871-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970555

RESUMO

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitors are effective for induction and maintenance of regulatory T cells (Tregs). OBJECTIVE: To assess the effects of conversion from calcineurin inhibitors (CNIs) to mTOR on the number of circulating Tregs and lymphocyte activation. PATIENTS AND METHODS: In 18 renal transplant recipients receiving CNI therapy (cyclosporine in 9, and tacrolimus in 9), treatment was converted to mTOR inhibitors (everolimus in 14, and rapamycin in 4). Peripheral blood samples were obtained before and 3 months after conversion. The number of circulating Tregs was measured using flow cytometry, and defined as CD4+/CD25high/CD127low/CD27+/CD62L+/CD45RO+/Foxp3+. Lymphocyte activation was assessed indirectly according to production of intracellular adenosine triphosphate (iATP) on polyclonal activation using a phytohemaglutinin assay (Immuknow; Cylex, Inc, Columbia, Maryland). RESULTS: In 15 patients (83.3%), the absolute number of Tregs increased significantly (P=.001) after conversion (median, 16.35 cells/mm3; 95% confidence interval [CI], 13.97-21.94) vs 3 months after conversion (32.03 cells/mm3; 95% CI, 26.25-41.66). The iATP production decreased from 326 ng/mL (95% CI, 302-419) to 248 ng/mL (95% CI, 196-318; P=.02), and increased in 4 patients (22.22%). No significant correlation was demonstrated between Treg concentration and change in iATP production. No rejection episodes were reported during follow-up. CONCLUSIONS: Despite the small number of patients in whom therapy was converted from CNI inhibitors to mTOR inhibitors, the data suggest an increase in the absolute number of Tregs after conversion. In addition, the concentration of activated peripheral CD4+ T cells decreased to nearly that associated with risk of infection due to overimmunosuppression.


Assuntos
Ativação Linfocitária , Linfócitos T Reguladores/citologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Humanos , Imunofenotipagem , Linfócitos T Reguladores/imunologia
14.
Transplant Proc ; 42(8): 2877-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970557

RESUMO

Studies of allotolerance in animal models do not usually consider the presence of preexisting memory T cells and activated immune status. However, humans are exposed throughout life to a multitude of external agents that enhance the immune memory. In this article, we consider the effect that a previous kidney transplant has on the number of regulatory T cells (Tregs), effector memory T cells (TEM), and central memory T cells (TCM). Sixty-three patients with end-stage renal disease were studied just before being transplanted (51 first transplants and 12 retransplants). The numbers of Tregs (CD4+ CD25highCD127lowCD27+CD62L+CD45RO+FOXP3+), TEM (CD3+CD45RO+CD62L+), and TCM (CD3+CD45RO+CD62L-) cell subsets were quantified in peripheral blood by flow cytometry. The absolute number of Tregs was slightly lower in patients with previous allografts (median, 95% confidence interval [CI]: 16.7 cells/mm3, 12-20.5) than in those who received their first transplants (median, 95% CI: 19.6 cells/mm3, 19.3-29.6; P-NS). Clearer differences were found with the number of CD3+ TCM, since the transplanted patients had lower numbers (238 cells/mm3, 153-323) than those who had not yet received transplants (378 cells/mm3, 317-439; P=.029). As a result, the TEM/TCM ratios of both CD4+ and CD8+ T cells in patients with previous allografts were higher than in those who received first transplants. In conclusion, the assessment of just the number of Tregs in renal transplant patients is not enough and must be read together with the number of TEM and TCM. The TEM:TCM ratio increases in patients with previous allografts, probably due to activation of the immune response in renal transplantation.


Assuntos
Memória Imunológica , Falência Renal Crônica/imunologia , Transplante de Rim/imunologia , Linfócitos T Reguladores/imunologia , Listas de Espera , Adulto , Idoso , Antígenos CD/imunologia , Humanos , Imunofenotipagem , Pessoa de Meia-Idade , Doadores de Tecidos
15.
Transplant Proc ; 42(8): 2908-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970567

RESUMO

BACKGROUND: Hypertension is common after renal transplantation, affecting as many as 80% of recipients. It is generally accepted that hypertension is associated with poor graft survival and reduced life expectancy because of increased cardiovascular risk factors. The prevalence of refractory hypertension in renal transplant recipients is unknown, and could be associated with a poor prognosis. OBJECTIVE: To investigate the effects of refractory hypertension on cardiovascular disease (CVD) after renal transplantation in 486 patients with grafts functioning for longer than 1 year. PATIENTS AND METHODS: Patients were classified into 2 groups: (1) 57 with refractory hypertension, that is, systolic blood pressure 130 mm Hg or greater or diastolic blood pressure 80 mm Hg or greater, and receiving treatment with at least 3 drugs, one of which was a diuretic; and (2) the remaining 429 patients. Patient and graft survival, and posttransplantation CVD were analyzed. RESULTS: Refractory hypertension was associated with male sex (82.5% vs 66.5% [P<.01]), poor renal function (mean [SD] serum creatinine concentration 2.2 [1.2] mg/dL vs 1.6 [0.6] mg/dL; Modification of Diet in Renal Disease score 39.2 [20.0] mL/min/1.73 m2 vs 49.2 [18.0] mL/min/1.73 m2 [P=.000]; and steroid therapy (94.7% vs 79.0% [P=.001]). In the group with refractory hypertension, 5-year patient and graft survival rates were lower, and the incidence of posttransplantation CVD was greater (relative risk, 1.7; 95% confidence interval, 1.05-2.18; P=.03). CONCLUSION: Refractory hypertension is an independent risk factor for increased cardiovascular morbidity and mortality in renal transplant recipients.


Assuntos
Doenças Cardiovasculares/etiologia , Hipertensão/complicações , Transplante de Rim , Adulto , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
16.
Transplant Proc ; 42(8): 2935-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970575

RESUMO

BACKGROUND: Some transplant recipients demonstrate an inadequate response to erythropoiesis-stimulating agents, or so-called erythropoietin (Epo) resistance. The cause is multifactorial. Resistance to EPO may entail a poor prognosis for the graft and the patient, although results in the literature are inconsistent, and long-term follow-up is lacking. OBJECTIVE: To evaluate whether the presence of Epo resistance at the beginning of the study was a predictive factor for graft and patient survival. MATERIALS AND METHODS: From 482 renal transplant recipients (Kidney Disease Outcomes Quality Initiative stage 3-4T) receiving Epo-stimulating agents in the Anemia and Renal Transplantation in Spain study, 101 were selected for the present study. Erythropoietin resistance was defined as a ratio of weekly Epo dosage/hemoglobin concentration>486,94 U/g/dL with a hemoglobin/<11 g/dL. Darbepoetin dosage was calculated in Epo equivalent units, with a 1:200 conversion factor. Patients were grouped as Epo-resistant (ER+) or not Epo-resistant (ER-), to assess whether Epo resistance was predictive of patient and graft survival. RESULTS: There were no differences in demographic data between the 2 groups except for a higher incidence of vascular, interstitial, and diabetes-related causes of chronic renal failure in the ER+ group. At 3 years posttransplantation, graft survival was 33% in the ER+ group vs 58% in the ER- group (P=.06), and patient survival was 52% in the ER+ group vs 88% in the ER- group (P=.008). Using a Cox regression model, at 3 years, the relative risk of graft failure was 1.96 in the ER+ group (95% CI, 0.93-3.12; P=.07), and of patient death was 3.9 (95% confidence interval, 1.30-11.63; P=.01). CONCLUSION: Erythropoietin resistance is an independent risk factor for death after renal transplantation.


Assuntos
Eritropoetina/uso terapêutico , Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Rim , Resistência a Medicamentos , Eritropoetina/farmacologia , Humanos , Prognóstico , Estudos Prospectivos
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