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1.
Transplant Proc ; 50(10): 3516-3520, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577229

RESUMEN

BACKGROUND: Exertional heatstroke is an extremely rare cause of fulminant hepatic failure. Maximal supportive care has failed to provide adequate survival in earlier studies. This is particularly true in cases accompanied by multiorgan failure. METHODS AND MATERIALS: Our prospectively collected transplant database was retrospectively reviewed to identify patients undergoing liver transplantation for heatstroke between January 1, 2012, and December 31, 2016. We report 3 consecutive cases of male patients with fulminant hepatic failure from exertional heatstroke. RESULTS: All patients developed multiorgan failure and required intubation, vasopressor support, and renal replacement therapy. All patients were listed urgently for liver transplantation and were supported with the molecular adsorbent recirculating system while awaiting transplantation. All patients underwent liver transplantation alone and are alive and well, with recovered renal function, normal liver allograft function, and no chronic sequelae of their multiorgan failure at more than one year. CONCLUSION: Extreme heatstroke leading to whole-body organ dysfunction and fulminant liver failure is a complex entity that may benefit from therapy using the Molecular Adsorbent Recirculating System while waiting for liver transplantation as a component of a multidisciplinary, multiorgan system approach.


Asunto(s)
Fluidoterapia/métodos , Golpe de Calor/complicaciones , Trasplante de Hígado/métodos , Insuficiencia Multiorgánica/etiología , Adulto , Fluidoterapia/instrumentación , Humanos , Fallo Hepático Agudo/etiología , Fallo Hepático Agudo/cirugía , Masculino , Insuficiencia Multiorgánica/cirugía , Estudios Retrospectivos , Adulto Joven
3.
Am J Transplant ; 13(10): 2743-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23915309

RESUMEN

Procurement of a facial vascularized composite allograft (VCA) should allow concurrent procurement of all solid organs and ensure their integrity. Because full facial procurement is time-intensive, "simultaneous-start" procurement could entail VCA ischemia over 12 h. We procured a total face osteomyocutaneous VCA from a brain-dead donor. Bedside tracheostomy and facial mask impression were performed preoperative day 1. Solid organ recovery included heart, lungs, liver, kidneys, and pancreas. Facial dissection time was 12 h over 15 h to diminish ischemia while awaiting recipient preparation. Solid organ recovery began at 13.5 h, during midfacial osteotomies, and concluded immediately after facial explantation. Facial thoracic and abdominal teams worked concurrently. Estimated blood loss was 1300 mL, requiring five units of pRBC and two units FFP. Urine output, MAP, pH and PaO2 remained normal. All organs had good postoperative function. We propose an algorithm that allows "face first, concurrent completion" recovery of a complex facial VCA by planning multiple pathways to expedient recovery of vital organs in the event of clinical instability. Beginning the recipient operation earlier may reduce waiting time due to extensive recipient scarring causing difficult dissection.


Asunto(s)
Algoritmos , Muerte Encefálica , Cara/cirugía , Trasplante Facial/métodos , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos/métodos , Adulto , Puntos Anatómicos de Referencia , Cara/irrigación sanguínea , Humanos , Masculino , Adulto Joven
4.
Am J Transplant ; 12(5): 1124-32, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22299822

RESUMEN

Donor pancreatic lymph node cells (PLNC) protect islet transplants in Non-obese diabetic (NOD) mice. We hypothesized that induced FoxP3(+) regulatory T cells (Tregs) were required for long-term islet engraftment. NOD or NOD.NON mice were treated with ALS (antilymphocyte serum) and transplanted with NOR islets +/-PLNC (5 × 10(7) ). In vivo proliferation and expansion of FoxP3(+) Tregs was monitored in spleen and PLN from ALS- and ALS/PLNC-treated recipient mice. Anti-CD25 depletion was used to determine the necessity of Tregs for tolerance. FoxP3(+) numbers significantly increased in ALS/PLNC-treated recipients compared to ALS-treated mice. In ALS/PLNC-treated mice, recipient-derived Tregs localized to the transplanted islets, and this was associated with intact, insulin-producing ß cells. Proliferation and expansion of FoxP3(+) Tregs was markedly increased in PLNC-treated mice with accepted islet grafts, but not in diabetic mice not receiving PLNC. Deletion of Tregs with anti-CD25 antibodies prevented islet graft tolerance and resulted in rejection. Adoptive transfer of Tregs to secondary NOD.scid recipients inhibited autoimmunity by cotransferred NOD effector T cells. Treg expansion induced by ALS/PLNC-treatment promoted long term islet graft survival. Strategies leading to Treg proliferation and localization to the transplant site represent a therapeutic approach to controlling recurrent autoimmunity.


Asunto(s)
Suero Antilinfocítico/administración & dosificación , Diabetes Mellitus Tipo 1/terapia , Supervivencia de Injerto/inmunología , Trasplante de Islotes Pancreáticos/inmunología , Islotes Pancreáticos/inmunología , Ganglios Linfáticos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Autoinmunidad , Diabetes Mellitus Tipo 1/inmunología , Femenino , Técnica del Anticuerpo Fluorescente , Factores de Transcripción Forkhead/metabolismo , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos NOD , Ratones SCID , Tolerancia al Trasplante/inmunología
5.
Am J Transplant ; 11(9): 1792-802, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21812920

RESUMEN

The first Banff proposal for the diagnosis of pancreas rejection (Am J Transplant 2008; 8: 237) dealt primarily with the diagnosis of acute T-cell-mediated rejection (ACMR), while only tentatively addressing issues pertaining to antibody-mediated rejection (AMR). This document presents comprehensive guidelines for the diagnosis of AMR, first proposed at the 10th Banff Conference on Allograft Pathology and refined by a broad-based multidisciplinary panel. Pancreatic AMR is best identified by a combination of serological and immunohistopathological findings consisting of (i) identification of circulating donor-specific antibodies, and histopathological data including (ii) morphological evidence of microvascular tissue injury and (iii) C4d staining in interacinar capillaries. Acute AMR is diagnosed conclusively if these three elements are present, whereas a diagnosis of suspicious for AMR is rendered if only two elements are identified. The identification of only one diagnostic element is not sufficient for the diagnosis of AMR but should prompt heightened clinical vigilance. AMR and ACMR may coexist, and should be recognized and graded independently. This proposal is based on our current knowledge of the pathogenesis of pancreas rejection and currently available tools for diagnosis. A systematized clinicopathological approach to AMR is essential for the development and assessment of much needed therapeutic interventions.


Asunto(s)
Autoanticuerpos/inmunología , Rechazo de Injerto/diagnóstico , Trasplante de Páncreas/inmunología , Guías de Práctica Clínica como Asunto , Rechazo de Injerto/inmunología , Humanos
6.
Am J Transplant ; 11(7): 1407-16, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21668624

RESUMEN

Vascularized composite allograft (VCA) transplantation (also referred to as composite tissue allotransplantation) has demonstrated clinical success in cases of hand, arm and face transplantation despite prior belief that skin provides an insurmountable barrier to allograft rejection. These overall good outcomes are facilitated by substantial immunosuppressive requirements in otherwise healthy patients, yet still demonstrate frequent rejection episodes. We developed a nonhuman primate model of facial segment allotransplantation to elucidate the unique pathophysiology and immunosuppressive requirements of VCA with addition of concomitant vascularized bone marrow (VBM). Heterotopically transplanted facial segment VCA with VBM treated only with tacrolimus and mycophenolate mofetil (MMF) demonstrated prolonged rejection-free survival, compared to VCA without VBM that demonstrated early rejection episodes and graft loss. While VCA with VBM demonstrated sporadic macrochimerism, acute and chronic rejection and graft loss occurred after discontinuation of immunosuppression. These data support an immunomodulatory role of VBM in VCA that reduces immunosuppressive requirements while providing improved outcomes.


Asunto(s)
Médula Ósea/irrigación sanguínea , Pared Abdominal/cirugía , Animales , Médula Ósea/efectos de los fármacos , Trasplante Facial/métodos , Femenino , Supervivencia de Injerto/efectos de los fármacos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Macaca fascicularis , Masculino , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapéutico , Tacrolimus/uso terapéutico , Quimera por Trasplante , Trasplante Homólogo
7.
Am J Transplant ; 9(2): 337-47, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19067659

RESUMEN

We undertook this study to assess the rate of poor early graft function (EGF) after laparoscopic live donor nephrectomy (lapNx) and to determine whether poor EGF is associated with diminished long-term graft survival. The study population consisted of 946 consecutive lapNx donors/recipient pairs at our center. Poor EGF was defined as receiving hemodialysis on postoperative day (POD) 1 through POD 7 (delayed graft function [DGF]) or serum creatinine >/= 3.0 mg/dL at POD 5 without need for hemodialysis (slow graft function [SGF]). The incidence of poor EGF was 16.3% (DGF 5.8%, SGF 10.5%), and it was stable in chronologic tertiles. Poor EGF was independently associated with worse death-censored graft survival (adjusted hazard ratio (HR) 2.15, 95% confidence interval (CI) 1.34-3.47, p = 0.001), worse overall graft survival (HR 1.62, 95% CI 1.10-2.37, p = 0.014), worse acute rejection-free survival (HR 2.75, 95% CI 1.92-3.94, p < 0.001) and worse 1-year renal function (p = 0.002). Even SGF independently predicted worse renal allograft survival (HR 2.54, 95% CI 1.44-4.44, p = 0.001). Risk factors for poor DGF included advanced donor age, high recipient BMI, sirolimus use and prolonged warm ischemia time. In conclusion, poor EGF following lapNx has a deleterious effect on long-term graft function and survival.


Asunto(s)
Funcionamiento Retardado del Injerto/fisiopatología , Rechazo de Injerto/epidemiología , Supervivencia de Injerto/fisiología , Trasplante de Riñón/fisiología , Riñón/fisiopatología , Donadores Vivos , Nefrectomía , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Creatinina/sangre , Femenino , Rechazo de Injerto/diagnóstico , Humanos , Incidencia , Laparoscopía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Diálisis Renal , Factores de Riesgo , Recolección de Tejidos y Órganos , Trasplante Homólogo , Resultado del Tratamiento , Isquemia Tibia
8.
Am J Transplant ; 8(11): 2316-24, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18801024

RESUMEN

Despite the common use of diagnostic pretransplant deceased donor kidney biopsy, there is no consensus on the prognostic significance of the pathologic findings. In order to assist clinicians with interpretation we analyzed 371 pretransplant biopsies and correlated the findings with graft failure. Glomerular pathology was assessed with percent glomerulosclerosis (GS), glomerular size and periglomerular fibrosis (PGF); vascular pathology with arterial wall-to-lumen ratio (WLR) and arteriolar hyalinosis and interstitial pathology with measurement of cumulative fibrosis and presence of scar. Using two-thirds of the study population as a model-development cohort, we found that biopsy features independently associated with an increased risk of graft failure were GS > or =15%, interlobular arterial WLR > or =0.5 and the presence of PGF, arteriolar hyalinosis or scar. The Maryland Aggregate Pathology Index (MAPI), was developed from these parameters and validated on the remaining one-third of the population. Five-year actuarial graft survival was 90% for kidneys with MAPI scores between 0 and 7, 63% for scores from 8 to 11 and 53% for scores from 12 to 15 (p < 0.001). We conclude MAPI may help transplant physicians estimate graft survival from the preimplantation biopsy findings, in clinical situations similar to this study population (cold ischemia over 24 h, GS < 25%).


Asunto(s)
Biopsia/métodos , Trasplante de Riñón/mortalidad , Trasplante de Riñón/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios de Cohortes , Femenino , Supervivencia de Injerto , Humanos , Riñón/patología , Enfermedades Renales/diagnóstico , Enfermedades Renales/patología , Trasplante de Riñón/estadística & datos numéricos , Masculino , Maryland , Persona de Mediana Edad , Resultado del Tratamiento
9.
Am J Transplant ; 8(6): 1237-49, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18444939

RESUMEN

Accurate diagnosis and grading of rejection and other pathological processes are of paramount importance to guide therapeutic interventions in patients with pancreas allograft dysfunction. A multi-disciplinary panel of pathologists, surgeons and nephrologists was convened for the purpose of developing a consensus document delineating the histopathological features for diagnosis and grading of rejection in pancreas transplant biopsies. Based on the available published data and the collective experience, criteria for the diagnosis of acute cell-mediated allograft rejection (ACMR) were established. Three severity grades (I/mild, II/moderate and III/severe) were defined based on lesions known to be more or less responsive to treatment and associated with better- or worse-graft outcomes, respectively. The features of chronic rejection/graft sclerosis were reassessed, and three histological stages were established. Tentative criteria for the diagnosis of antibody-mediated rejection were also characterized, in anticipation of future studies that ought to provide more information on this process. Criteria for needle core biopsy adequacy and guidelines for pathology reporting were also defined. The availability of a simple, reproducible, clinically relevant and internationally accepted schema for grading rejection should improve the level of diagnostic accuracy and facilitate communication between all parties involved in the care of pancreas transplant recipients.


Asunto(s)
Rechazo de Injerto/clasificación , Rechazo de Injerto/patología , Trasplante de Páncreas , Páncreas/patología , Trasplante Homólogo/patología , Biopsia , Rechazo de Injerto/diagnóstico , Humanos
10.
Am J Transplant ; 8(2): 355-65, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18093266

RESUMEN

Improvements in human immunodeficiency virus (HIV)-associated mortality make it difficult to deny transplantation based upon futility. Outcomes in the current management era are unknown. This is a prospective series of liver or kidney transplant recipients with stable HIV disease. Eleven liver and 18 kidney transplant recipients were followed for a median of 3.4 years (IQR [interquartile range] 2.9-4.9). One- and 3-year liver recipients' survival was 91% and 64%, respectively; kidney recipients' survival was 94%. One- and 3-year liver graft survival was 82% and 64%, respectively; kidney graft survival was 83%. Kidney patient and graft survival were similar to the general transplant population, while liver survival was similar to the older population, based on 1999-2004 transplants in the national database. CD4+ T-cell counts and HIV RNA levels were stable; and there were two opportunistic infections (OI). The 1- and 3-year cumulative incidence (95% confidence intervals [CI]) of rejection episodes for kidney recipients was 52% (28-75%) and 70% (48-92%), respectively. Two-thirds of hepatitis C virus (HCV)-infected patients, but no patient with hepatitis B virus (HBV) infection, recurred. Good transplant and HIV-related outcomes among kidney transplant recipients, and reasonable outcomes among liver recipients suggest that transplantation is an option for selected HIV-infected patients cared for at centers with adequate expertise.


Asunto(s)
Infecciones por VIH/complicaciones , Trasplante de Riñón/estadística & datos numéricos , Trasplante de Hígado/estadística & datos numéricos , Adulto , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Cadáver , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Infecciones por VIH/tratamiento farmacológico , Humanos , Trasplante de Riñón/inmunología , Trasplante de Hígado/inmunología , Donadores Vivos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Donantes de Tejidos/estadística & datos numéricos , Resultado del Tratamiento , Carga Viral
11.
Am J Transplant ; 7(6): 1515-25, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17511680

RESUMEN

Kidneys from organ donors who have behaviors that place them at increased risk for infection with human immunodeficiency virus (HIV) or hepatitis C virus (HCV) are often discarded, even if viral screening tests are negative. This study compared policies that would either 'Discard' or 'Transplant' kidneys from Centers for Disease Control classified increased-risk donors (CDC-IRDs) using a decision analytic Markov model of renal failure treatment modalities. Base-case CDC-IRDs were current injection drug users (IDUs) with negative antibody and nucleic acid testing (NAT) for HIV and HCV, comprising 5% of kidney donors. Compared to a CDC-IRD kidney 'Discard' policy, the 'Transplant' policy resulted in higher patient survival, a greater number of quality-adjusted life-years (QALYs) (5.6 vs. 5.1 years per patient), more kidney transplants (990 vs. 740 transplants per 1000 patients) and lower cost of care ($60 000 vs. $71 000 per QALY). The total number of viral infections was lower with the 'Transplant' policy (13.1 vs. 14.8 infections per 1000 patients over 20 years), because the 'Discard' policy led to more time on hemodialysis, with a higher HCV incidence. We recommend that kidneys from NAT-negative CDC-IRDs be considered for transplantation since the practice is estimated to be beneficial from both the societal and individual patient perspective.


Asunto(s)
Infecciones por VIH/epidemiología , Hepatitis C/epidemiología , Trasplante de Riñón/fisiología , Donantes de Tejidos/estadística & datos numéricos , Humanos , Fallo Renal Crónico/cirugía , Fallo Renal Crónico/terapia , Trasplante de Riñón/efectos adversos , Cadenas de Markov , Selección de Paciente , Diálisis Renal , Medición de Riesgo , Asunción de Riesgos , Resultado del Tratamiento
12.
Am J Transplant ; 7(6): 1572-83, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17511682

RESUMEN

Mammalian Target-of-Rapamycin inhibitors (mTOR inhibitors) can be used to replace the calcineurin inhibitors (CNIs) to prevent progression in chronic kidney disease (CKD) following organ transplantation. Discontinuation of tacrolimus in 136 recipients of kidney transplants with progressive renal dysfunction significantly decreased the rate of loss of estimated glomerular filtration rate (eGFR, mL/min/1.73 m(2)) (pre-intervention vs. post-intervention slopes, -0.013 vs. -0.002, p < 0.0001). Discontinuation of tacrolimus was associated with a sustained and significant improvement in graft function (pre-eGFR vs. post-eGFR; 26.0 +/- 1.1 vs. 47.4 +/- 2.1, p < 0.0001) in 74% of patients. This intervention was ineffective if the mean and (median) values of creatinine (mg/dL) and eGFR were 3.8 +/- 0.2 (3.4) and 18.4 +/- 1.9 (22.4), respectively, at the time of conversion therapy. During the follow-up (range, 1.5-34.6, months), a total of 13 patients had their first acute rejection following the conversion therapy, an annual incidence of less than 10% and none of these episodes resulted in graft loss. The salutary effects of sirolimus therapy following discontinuation of tacrolimus in patients with moderate to severe graft dysfunction due to allograft nephropathy even in high-risk patients improves kidney function and prevents acute rejection.


Asunto(s)
Inhibidores de la Calcineurina , Inmunosupresores/uso terapéutico , Enfermedades Renales/inmunología , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/inmunología , Sirolimus/uso terapéutico , Biopsia , Enfermedad Crónica , Esquema de Medicación , Femenino , Tasa de Filtración Glomerular , Humanos , Enfermedades Renales/prevención & control , Pruebas de Función Renal , Trasplante de Riñón/patología , Masculino , Persona de Mediana Edad , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapéutico , Complicaciones Posoperatorias/inmunología , Complicaciones Posoperatorias/prevención & control , Sirolimus/administración & dosificación , Trasplante Homólogo/patología
13.
Transplant Proc ; 36(4): 1050-1, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15194365

RESUMEN

Machine pulsatile perfusion for whole pancreas preservation might improve yield, viability, and function of human islets recovered after prolonged cold ischemia times. Four human pancreata were procured from cadaver donors (1 non-heart-beating donor) and stored in cold University of Wisconsin (UW) solution for a mean 13 hours prior to placement on a machine pulsatile perfusion device. The four pancreata were perfused for 4 hours with UW solution before undergoing islet isolation. Islets were quantified, viability was assessed, and insulin secretion was measured. Results were compared with nonpumped islet isolations stratified for cold ischemia time (CIT) <8 hours or cold ischemia time >8 hours. The islet yield for the four pumped pancreata was 3435 (+/-1951) islet equivalents/gram pancreas tissue (IEQ/g), compared with a mean yield of 5134 (+/-2700) IEQ/g and 2640 (+/-1000) IEQ/g from pancreas with <8 hours and >8 hours CIT, respectively. The mean viability after machine pulsatile perfusion was 86% (vs 74% and 74% for the <8 hour and >8 hour CIT groups). The mean viable yield (total yield x viability) was 2937 IEQ/g for machine perfusion, compared with 3799 IEQ/g and 1937 IEQ/g from pancreata with <8 hours and >8 hours CIT, respectively. The insulin secretion index of islets after machine perfusion was 6.4, compared with indices of 1.9 and 1.8 for the <8 hour and >8 hour CIT groups. This preliminary data indicates that low-flow machine pulsatile perfusion of pancreata with prolonged cold ischemia time can result in excellent yield, viability, and function.


Asunto(s)
Trasplante de Islotes Pancreáticos/métodos , Páncreas , Adenosina , Alopurinol , Cadáver , Glutatión , Humanos , Insulina , Soluciones Preservantes de Órganos , Perfusión , Rafinosa , Donantes de Tejidos , Resultado del Tratamiento
14.
Transplant Proc ; 36(3): 758-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15110653

RESUMEN

Polyoma virus allograft nephropathy often results in accelerated graft loss despite reduction of immunosuppression and/or treatment with antiviral agents. Irreversible renal fibrosis due to late diagnosis is likely to be one of the important causes of treatment failure. Early biopsy in 14 patients resulted in stable graft function after a mean follow-up of 22 months.


Asunto(s)
Trasplante de Riñón/patología , Infecciones por Polyomavirus/patología , Biopsia , Creatinina/sangre , Humanos , Inmunosupresores/uso terapéutico , Trasplante de Riñón/inmunología , Reacción en Cadena de la Polimerasa , Poliomavirus/genética , Poliomavirus/aislamiento & purificación , Resultado del Tratamiento
15.
Transplant Proc ; 36(3): 780-1, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15110661

RESUMEN

Thirty intraoperative needle core biopsies of well-functioning pancreas allografts were performed from 2 days to 7 years posttransplantation (mean 15.4 months). Most samples (83.3%) lacked significant inflammation or fibrosis. The five patients who showed features of ongoing low-grade acute rejection experienced premature graft losses due to chronic rejection. There were no complications related to the intraoperative biopsy itself.


Asunto(s)
Biopsia con Aguja , Rechazo de Injerto/patología , Hallazgos Incidentales , Monitoreo Intraoperatorio , Trasplante de Páncreas/patología , Adulto , Femenino , Fibrosis , Humanos , Inflamación , Laparotomía , Masculino , Persona de Mediana Edad , Trasplante Homólogo/patología
16.
Transplantation ; 72(9): 1548-55, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11707744

RESUMEN

BACKGROUND: We have previously reported that activated CD8+TCRalphabeta+ cells that express high levels of the beta7 integrin CD103 (formerly alphaE, MLA) are present at the graft site during clinical renal allograft rejection. This observation potentially provides new insight into the mechanisms underlying renal allograft destruction because the ligand of CD103 is the epithelial cell-specific molecule E-cadherin, which is known to be expressed by critical graft functional elements such as the renal tubular epithelium. We herein used combined fluorescence-activated cell sorter (FACS) and immunohistochemical (IHC) analyses of transplant nephrectomy (TN) specimens to demonstrate that CD103+ cytolytic T lymphocytes (CTLs) specifically home to the graft epithelium during rejection episodes. METHODS: Serial sections of TN specimens undergoing histologically confirmed cellular rejection (n=7) were stained with anti-CD8 or anti-CD103 and were scored for the presence of positively stained cells within the tubular basement membrane. Freshly isolated graft-infiltrating lymphocytes were subjected to three-color FACS analyses to define the extended phenotypic characteristics of CD103+ cells detected by IHC. RESULTS: CD103+ cells in all specimens were biased towards an intratubular localization. On average, the percentage of CD103+ cells with an intraepithelial localization was 52.2+/-13.1 compared to 12.0+/-3.5 for pan CD8+ cells (mean+/-SE, n=5). FACS analyses confirmed that CD103+ cells detected by IHC exhibited the salient characteristics of CD8+ CTLs (large CD8+TCRalphabeta+CD62L-CD11a(hi)perforin+). The CD103- subset of graft-infiltrating CD8 cells also exhibited a CTL phenotype, but these were predominantly restricted to the graft interstitium. CONCLUSIONS: These data implicate CD103 as a homing receptor that targets graft-infiltrating CD8+ CTLs to the graft epithelium. Given the strong association of tubulitis with clinical rejection, these data are consistent with a role for the CD103+ CTL subset as an effector mechanism in renal allograft destruction.


Asunto(s)
Antígenos CD/inmunología , Cadenas alfa de Integrinas , Trasplante de Riñón/inmunología , Trasplante Homólogo/inmunología , Linfocitos T CD8-positivos/inmunología , Epitelio/inmunología , Antígenos HLA-D/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Prueba de Histocompatibilidad , Humanos , Integrinas/inmunología , Corteza Renal/microbiología , Trasplante de Riñón/patología , Fenotipo , Receptores Mensajeros de Linfocitos/inmunología
17.
Ann Surg ; 234(5): 689-96, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11685034

RESUMEN

OBJECTIVE: To compare portal and systemic venous drainage of pancreas transplants and demonstrate an immunologic and survival superiority of portal venous drainage. SUMMARY BACKGROUND DATA: Traditionally, solitary pancreas transplants have been performed using systemic venous and bladder drainage, but more recently, the advantages of enteric drainage have been well documented. Although physiologic benefits for portal venous drainage have been described, the impact of portal venous drainage, especially with solitary pancreas transplants, has yet to be determined. METHODS: Since August 1995, 280 pancreas transplants with enteric duct drainage were analyzed. One hundred and seventeen were simultaneous pancreas and kidney (SPK), 63 with systemic venous drainage (SV) and 54 with portal venous drainage (PV). The remainder were solitary transplants; 97 pancreas after kidney (PAK; 42 SV and 55 PV) and 66 transplants alone (PTA; 26 SV and 40 PV). Immunosuppressive therapy was equivalent for both groups. RESULTS: The groups were similar with respect to recipient characteristics and HLA matching. Thirty-six month graft survival for all transplants was 79% for PV and 65% for SV (P =.008). By category, SPK graft survival was 74% for PV and 76% for SV, PAK graft survival was 70% for PV and 56% for SV, and PTA graft survival was 84% for PV and 50% for SV. The rate of at least one rejection episode was also significantly higher in the SV group. At 36 months, for all pancreas transplants, the rejection rate was 21% for PV and 52% for SV (P <.0001). For SPK, rejection rates were 9% for PV and 45% for SV. For PAK, rejection rates were 16% for PV and 65% for SV, and for PTA 36% for PV and 51% for SV. The rejection rates for kidneys following SPK were also lower in the PV group (26% versus 43% for SV). Furthermore, the grades of rejection were milder in PV for all transplants (P =.017). By multivariate analysis, portal venous drainage was the only parameter that significantly affected rejection. CONCLUSION: Graft survival and rejection is superior for PV. These clinical findings are consistent with published reports of experimentally induced portal tolerance and strongly argue that PV drainage should be the procedure of choice for pancreas transplantation.


Asunto(s)
Trasplante de Páncreas/métodos , Vena Porta/cirugía , Adulto , Anastomosis en-Y de Roux , Anastomosis Quirúrgica , Diabetes Mellitus Tipo 1/cirugía , Duodeno/cirugía , Femenino , Supervivencia de Injerto , Humanos , Vena Ilíaca/cirugía , Inmunosupresores/uso terapéutico , Yeyuno/cirugía , Trasplante de Riñón/métodos , Masculino , Estudios Retrospectivos
18.
J Clin Pharmacol ; 41(8): 861-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11504274

RESUMEN

The study was performed to compare the efficacy and side effects of azathioprine (AZA) and mycophenolate mofetil (MMF) in conjunction with cyclosporine or tacrolimus and steroids for the prevention of acute pancreas rejection during the first 6 months of pancreas transplantation. In this case-controlled study, MMF is compared with historical controls of AZA in the prevention of acute pancreas rejection. The primary measures of treatment efficacy were patient and pancreas survival rate at 6 months after transplantation. Secondary efficacy measures were the occurrence of biopsy-proven pancreas rejections and the use of antilymphocyte preparations for rejection treatment. A total of 111 pancreas transplant patients (57 in the AZA group and 54 in the MMF group) were evaluated. The 6-month patient survival rate was 96% in the AZA group versus 97% in the MMF group (p = 0.57). The 6-month pancreas graft survival rate was 88% in the AZA group versus 91% in the MMF group (p = 0.29). However, biopsy-proven rejection episodes during the first 6 months of transplantation were significantly lower with MMF (46%) than with AZA (69%) (p = 0.01). In addition, patients in the AZA group received a greater number of full courses of antilymphocyte therapy as a rejection treatment (p = 0.004). Overall, the frequency of adverse events was similar, although the MMF group experienced higher incidences of gastrointestinal adverse events. In conclusion, compared with AZA, MMF significantly reduces the rate of biopsy-proven pancreas rejection during the first 6 months of transplantation and is well tolerated, except for gastrointestinal adverse events.


Asunto(s)
Azatioprina/uso terapéutico , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapéutico , Trasplante de Páncreas/inmunología , Enfermedad Aguda , Adulto , Femenino , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Páncreas/mortalidad , Tasa de Supervivencia
19.
Transplantation ; 71(12): 1784-91, 2001 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-11455259

RESUMEN

BACKGROUND: Graft losses due to leaks, bleeding, thrombosis, infections, and early pancreatitis are grouped together under the category of technical failure. Among these complications, massive vascular thrombosis continues to be the most important cause of early graft loss due to technical failure. Pathological evaluation of most allografts lost early in the posttransplantation period shows vascular thrombosis with associated proportional parenchymal necrosis. The morphological findings in allografts that are considered to be lost due to technical failure has not been systematically addressed. In particular, the role of acute rejection in early graft loss has not been well studied. METHODS: Seventy-four consecutive pancreas graft pancreatectomies were studied histologically to evaluate for thrombosis (recent versus organized), type of vessel involved by thrombosis (arteries, veins, or both), acute rejection grade, chronic rejection grade, endotheliitis, transplant arteritis, coagulation necrosis, acute pancreatitis, presence of infectious organisms, transplant (obliterative) arteriopathy, neoplasia, relative proportions of alpha and beta islet cells, and immunoglobulin and complement deposition. The histological findings were correlated with donor and recipient data as well as clinical presentation. RESULTS: In 23 out of 39 grafts lost in the first 4 weeks posttransplantation, the only pathological changes found were vascular thrombosis and bland ischemic parenchymal necrosis. In these cases, no underlying vascular pathology or any other specific histological change was identified. Most of these grafts (78%) were lost in less than 48 hr and all in the first 2 weeks posttransplantation. Massive vascular thrombosis occurring in an otherwise histologically normal pancreas was the most common cause of graft loss in the first 4 weeks posttransplantation (59%). In most of the remaining cases (33%), although the clinical presentation suggested technical failure, there was clear histological evidence that the massive thrombosis resulted from vascular injury due to immune damage (acute and hyperacute rejection). Increased incidence of early graft thrombosis was seen in grafts from older donors and longer cold ischemia times. After the first month posttransplantation, graft pancreatectomies revealed a wider variety of pathological processes that included severe acute rejection, combined acute and chronic rejection, chronic rejection, and infections. Acute and chronic vascular thrombosis in large and small vessels was commonly seen at all times posttransplantation; chronic, organized thrombosis was strongly associated with chronic rejection. CONCLUSIONS: (a) Early acute thrombosis occurring in a histologically normal pancreas defines a true technical failure. This study showed that acute rejection leading to massive thrombosis, which clinically simulates technical failure, results in a significant proportion of early graft losses. (b) Systematic histological evaluation of failed grafts is absolutely necessary for the accurate classification of the cause of graft loss. (c) There is morphological evidence that chronically ongoing thrombosis is an important, common, contributing factor for late graft loss.


Asunto(s)
Rechazo de Injerto/patología , Trasplante de Páncreas , Adulto , Femenino , Glucagón/metabolismo , Rechazo de Injerto/complicaciones , Rechazo de Injerto/metabolismo , Humanos , Insulina/metabolismo , Masculino , Persona de Mediana Edad , Páncreas/metabolismo , Páncreas/patología , Enfermedades Pancreáticas/etiología , Enfermedades Pancreáticas/patología , Trombosis/etiología , Trombosis/patología
20.
Ann Surg ; 233(5): 645-51, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11323503

RESUMEN

OBJECTIVE: To examine the ability of several large, experienced transplantation centers to perform right-sided laparoscopic donor nephrectomy safely with equivalent long-term renal allograft function. SUMMARY BACKGROUND DATA: Early reports noted a higher incidence of renal vein thrombosis and eventual graft loss. However, exclusion of right-sided donors would deprive a significant proportion of donors a laparoscopically harvested graft. METHODS: A retrospective review was performed among 97 patients from seven centers performing right-sided laparoscopic donor nephrectomy. Surgical and postoperative demographic factors were evaluated. Complications were identified and long-term renal allograft function was compared with historical left-sided laparoscopic donor nephrectomy cohorts. RESULTS: Right laparoscopic donor nephrectomy was performed for varying reasons, including multiple left renal arteries or veins, smaller right kidney, or cystic right renal mass. Mean surgical time was 235.0 +/- 66.7 minutes, with a mean blood loss of 139 +/- 165.8 mL. Conversion was required in three patients secondary to bleeding or anatomical anomalies. Mean warm ischemic time was limited at 238 +/- 112 seconds. Return to diet was achieved on average after 7.5 +/- 2.3 hours, with mean discharge at 54.6 +/- 22.8 hours. Two grafts were lost during the early experience of these centers to renal vein thrombosis. Both surgical and postoperative complications were limited, with few long-term adverse effects. Mean serum creatinine levels were higher than open and left laparoscopic donor nephrectomy on postoperative day 1, but at all remaining intervals the right laparoscopic donors had equivalent creatinine values. CONCLUSIONS: These results confirm that right laparoscopic donor nephrectomy provides similar patient benefits, including early return to diet and discharge. Long-term creatinine values were no higher than in traditional open donor or left laparoscopic donor cohorts. These results establish that early concerns about high thrombosis rates are not supported by a multiinstitutional review of laparoscopic right donor nephrectomies.


Asunto(s)
Laparoscopía , Donadores Vivos , Nefrectomía/métodos , Adolescente , Adulto , Anciano , Creatinina/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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