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1.
Transplant Proc ; 50(10): 3913-3916, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30471832

RESUMEN

Kidneys from donors with blood type A2 can be successfully transplanted into blood type B and O recipients without the need for desensitization if the recipient's starting anti-A hemagglutinin titer is within an acceptable range. National kidney allocation policy now offers priority for eligible B recipients to receive A2 or A2B deceased donor kidneys, and therefore, the frequency with which A2 or A2B to B transplants will occur is expected to increase. The precise mechanisms by which antibody-mediated rejection is averted in these cases despite the presence of both circulating anti-A antibody and expression of the A2 antigen on the graft endothelium are not known. Whether this process mirrors proposed mechanisms of accommodation, which can occur in recipients of ABO incompatible transplants, is also not known. Repeated exposure to mismatched antigens after retransplantation could elicit memory responses resulting in antibody rebound and accelerated antibody-mediated rejection. Whether this would occur in the setting of repeated A2 donor exposure was uncertain. Here we report the case of a patient with history of a prior A2 to B transplant which failed owing to nonimmunologic reasons; the patient successfully underwent a repeat A2 to B transplant. Neither rebound in anti-A2 antibody nor clinical evidence of antibody-mediated rejection were observed after the transplant. Current kidney allocation will likely enable more such transplants in the future, and this may provide a unique patient population in whom the molecular mechanisms of incompatible graft accommodation may be investigated.


Asunto(s)
Incompatibilidad de Grupos Sanguíneos/inmunología , Trasplante de Riñón/métodos , Reoperación , Sistema del Grupo Sanguíneo ABO/inmunología , Anciano , Anticuerpos , Tipificación y Pruebas Cruzadas Sanguíneas , Supervivencia de Injerto/inmunología , Humanos , Masculino , Donantes de Tejidos
2.
Transplant Proc ; 48(8): 2689-2694, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27788802

RESUMEN

BACKGROUND: Immunoglobulin (Ig)A nephropathy is the most common primary glomerulonephritis worldwide, with a high recurrence rate after kidney transplantation. The aim of this study was to assess allograft survival, impact of recurrence on allograft function, and risk factors for post-transplant IgA recurrence. METHODS: We identified 104 patients with IgA nephropathy who underwent kidney transplantation at our center between 1993 and 2014. Fourteen patients underwent more than one allograft. RESULTS: IgA recurrence was documented in 23 (19%) allografts. Median time to recurrence was 6.75 years (interquartile range, 1.4-9.2 years). Twelve of the 23 recurrences were from living related donors (P = .07), and those with younger age at transplantation (37.7 ± 2.3 vs 44 ± 1.3, P = .05) were at higher risk of recurrence. Mean allograft survival was reduced in those with recurrence (6.5 ± 5.1 years) compared with those without recurrence (10.4 ± 7.5 years). At 6 years after transplant, allograft failure was documented in 52% of the recurrence group compared with 10% in the non-recurrence group (P = .002). CONCLUSIONS: IgA recurrence after transplant is an important cause of allograft loss. Living related donors and younger age at transplantation are associated with high recurrence rate. Close monitoring and treatment of recurrence are crucial.


Asunto(s)
Glomerulonefritis por IGA/patología , Glomerulonefritis por IGA/cirugía , Trasplante de Riñón , Adulto , Femenino , Glomerulonefritis por IGA/complicaciones , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Factores de Riesgo
3.
Am J Transplant ; 16(10): 3041-3045, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27214874

RESUMEN

Patients requiring desensitization prior to renal transplantation are at risk for developing severe antibody-mediated rejection (AMR) refractory to treatment with plasmapheresis and intravenous immunoglobulin (PP/IVIg). We have previously reported success at graft salvage, long-term graft survival and protection against transplant glomerulopathy with the use of eculizumab and splenectomy in addition to PP/IVIg. Splenectomy may be an important component of this combination therapy and is itself associated with a marked reduction in donor-specific antibody (DSA) production. However, splenectomy represents a major operation, and some patients with severe AMR have comorbid conditions that substantially increase their risk of complications during and after surgery. In an effort to spare recipients the morbidity of a second operation, we used splenic irradiation in lieu of splenectomy in two incompatible live donor kidney transplant recipients with severe AMR in addition to PP/IVIg, rituximab and eculizumab. This novel approach to the treatment of severe AMR was associated with allograft salvage, excellent graft function and no short- or medium-term adverse effects of the radiation therapy. One-year surveillance biopsies did not show transplant glomerulopathy (tg) on light microscopy, but microcirculation inflammation and tg were present on electron microscopy.


Asunto(s)
Rechazo de Injerto/radioterapia , Supervivencia de Injerto/efectos de la radiación , Isoanticuerpos/efectos adversos , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Bazo/efectos de la radiación , Esplenectomía/efectos adversos , Adulto , Desensibilización Inmunológica , Femenino , Rayos gamma , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunosupresores/uso terapéutico , Pruebas de Función Renal , Persona de Mediana Edad , Plasmaféresis , Complicaciones Posoperatorias , Pronóstico , Bazo/inmunología , Bazo/patología
4.
Am J Transplant ; 16(1): 292-300, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26317315

RESUMEN

The Open Payments Program (OPP) was recently implemented to publicly disclose industry payments to physicians, with the goal of enabling patient awareness of potential conflicts of interests. Awareness of OPP, its data, and its implications for transplantation are critical. We used the first wave of OPP data to describe industry payments made to transplant surgeons. Transplant surgeons (N = 297) received a total of $759 654. The median (interquartile range [IQR]) payment to a transplant surgeon was $125 ($39-1018), and the highest payment to an individual surgeon was $83 520; 122 surgeons received <$100, and 17 received >$10 000. A higher h-index was associated with 30% higher chance of receiving >$1000 (relative risk/10 unit h-index increase = 1.18 1.301.44 , p < 0.001). The highest payment category was consulting fees, with a total of $314 448 paid in this reported category. Recipients of consulting fees had higher h-indices, median (IQR) of 20 (10-35) versus nine (3-17) (p < 0.001). Ten of 122 companies accounted for 62% of all payments. Kidney transplant and liver transplant (LT) centers that received >$1000 had higher center volumes (p < 0.001). LT centers that received payments of >$1000 had a higher percentage of private-insurance/self-pay patients (p < 0.01). Continued surveillance of industry payments may further elucidate the relationship between industry payments and physician practices.


Asunto(s)
Bases de Datos Factuales/economía , Industria Farmacéutica/economía , Trasplante de Órganos/economía , Pautas de la Práctica en Medicina/economía , Cirujanos/economía , Revelación de la Verdad , Gastos en Salud , Humanos , Patient Protection and Affordable Care Act/legislación & jurisprudencia , Informe de Investigación
5.
Am J Transplant ; 16(1): 213-20, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26317487

RESUMEN

The updated Banff classification allows for the diagnosis of antibody-mediated rejection (AMR) in the absence of peritubular capillary C4d staining. Our objective was to quantify allograft loss risk in patients with consistently C4d-negative AMR (n = 51) compared with C4d-positive AMR patients (n = 156) and matched control subjects without AMR. All first-year posttransplant biopsy results from January 2004 through June 2014 were reviewed and correlated with the presence of donor-specific antibody (DSA). C4d-negative AMR patients were not different from C4d-positive AMR patients on any baseline characteristics, including immunologic risk factors (panel reactive antibody, prior transplant, HLA mismatch, donor type, DSA class, and anti-HLA/ABO-incompatibility). C4d-positive AMR patients were significantly more likely to have a clinical presentation (85.3% vs. 54.9%, p < 0.001), and those patients presented substantially earlier posttransplantation (median 14 [interquartile range 8-32] days vs. 46 [interquartile range 20-191], p < 0.001) and were three times more common (7.8% vs 2.5%). One- and 2-year post-AMR-defining biopsy graft survival in C4d-negative AMR patients was 93.4% and 90.2% versus 86.8% and 82.6% in C4d-positive AMR patients, respectively (p = 0.4). C4d-negative AMR was associated with a 2.56-fold (95% confidence interval, 1.08-6.05, p = 0.033) increased risk of graft loss compared with AMR-free matched controls. No clinical characteristics were identified that reliably distinguished C4d-negative from C4d-positive AMR. However, both phenotypes are associated with increased graft loss and thus warrant consideration for intervention.


Asunto(s)
Complemento C4b/inmunología , Rechazo de Injerto/etiología , Isoanticuerpos/inmunología , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias , Adulto , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/patología , Supervivencia de Injerto , Humanos , Isoanticuerpos/sangre , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo
6.
Am J Transplant ; 15(2): 489-98, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25611786

RESUMEN

Unlike antibody-mediated rejection (AMR) with clinical features, it remains unclear whether subclinical AMR should be treated, as its effect on allograft loss is unknown. It is also uncertain if AMR's effect is homogeneous across donor (deceased/live) and (HLA/ABO) antibody types. We compared 219 patients with AMR (77 subclinical, 142 clinical) to controls matched on HLA/ABO-compatibility, donor type, prior transplant, panel reactive antibody (PRA), age and year. One and 5-year graft survival in subclinical AMR was 95.9% and 75.7%, compared to 96.8% and 88.4% in matched controls (p = 0.0097). Subclinical AMR was independently associated with a 2.15-fold increased risk of graft loss (95% CI: 1.19-3.91; p = 0.012) compared to matched controls, but not different from clinical AMR (p = 0.13). Fifty three point two percent of subclinical AMR patients were treated with plasmapheresis within 3 days of their AMR-defining biopsy. Treated subclinical AMR patients had no difference in graft loss compared to matched controls (HR 1.73; 95% CI: 0.73-4.05; p = 0.21), but untreated subclinical AMR patients did (HR 3.34; 95% CI: 1.37-8.11; p = 0.008). AMR's effect on graft loss was heterogeneous when stratified by compatible deceased donor (HR = 4.73; 95% CI: 1.57-14.26; p = 0.006), HLA-incompatible deceased donor (HR = 2.39; 95% CI: 1.10-5.19; p = 0.028), compatible live donor (no AMR patients experienced graft loss), ABO-incompatible live donor (HR = 6.13; 95% CI: 0.55-67.70; p = 0.14) and HLA-incompatible live donor (HR = 6.29; 95% CI: 3.81-10.39; p < 0.001) transplant. Subclinical AMR substantially increases graft loss, and treatment seems warranted.


Asunto(s)
Anticuerpos/inmunología , Rechazo de Injerto/epidemiología , Rechazo de Injerto/inmunología , Trasplante de Riñón , Donadores Vivos , Adulto , Aloinjertos , Biopsia , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Histocompatibilidad/inmunología , Humanos , Incidencia , Riñón/patología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores de Tiempo
7.
Am J Transplant ; 14(2): 459-65, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24400968

RESUMEN

Renal transplantation in patients with antiphospholipid antibodies has historically proven challenging due to increased risk for thrombosis and allograft failure. This is especially true for patients with antiphospholipid antibody syndrome (APS) and its rare subtype, the catastrophic antiphospholipid antibody syndrome (CAPS). Since a critical mechanism of thrombosis in APS/CAPS is one mediated by complement activation, we hypothesized that preemptive treatment with the terminal complement inhibitor, eculizumab, would reduce the extent of vascular injury and thrombosis, enabling renal transplantation for patients in whom it would otherwise be contraindicated. Three patients with APS, two with a history of CAPS, were treated with continuous systemic anticoagulation together with eculizumab prior to and following live donor renal transplantation. Two patients were also sensitized to human leukocyte antigens (HLA) and required plasmapheresis for reduction of donor-specific antibodies. After follow-up ranging from 4 months to 4 years, all patients have functioning renal allografts. No systemic thrombotic events or early graft losses were observed. While the appropriate duration of treatment remains to be determined, this case series suggests that complement inhibitors such as eculizumab may prove to be effective in preventing the recurrence of APS after renal transplantation.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Síndrome Antifosfolípido/prevención & control , Inactivadores del Complemento/uso terapéutico , Rechazo de Injerto/prevención & control , Fallo Renal Crónico/complicaciones , Trasplante de Riñón/efectos adversos , Complicaciones Posoperatorias/prevención & control , Adulto , Síndrome Antifosfolípido/etiología , Estudios de Seguimiento , Rechazo de Injerto/etiología , Humanos , Fallo Renal Crónico/cirugía , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Recurrencia , Inducción de Remisión
8.
Am J Transplant ; 10(8): 1842-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20659090

RESUMEN

The recent national focus on patient safety has led to a re-examination of the risks and benefits of nighttime surgery. In liver transplantation, the hypothetical risks of nighttime operation must be weighed against either the well-established risks of prolonging cold ischemia or the potential risks of strategies to manipulate operative start times. A retrospective review was conducted of 578 liver transplants performed at a single institution between 1995 and 2008 to determine whether the incidence of postoperative complications correlated with operative start times. We hypothesized that no correlation would be observed between complication rates and operative start times. No consistent trends in relative risk of postoperative wound, vascular, biliary, or other complications were observed when eight 3-h time strata were compared. When two 12-h time strata (night, 3 p.m.-3 a.m., and day, 3 a.m.-3 p.m.) were compared, complications were not significantly different, but nighttime operations were longer in duration, and were associated a twofold greater risk of early death compared to daytime operations (adjusted OR 2.9, 95% CI 1.16-7.00, p = 0.023), though long-term survival did not differ significantly between the subgroups. This observation warrants further evaluation and underscores the need to explore and identify institution-specific practices that ensure safe operations regardless of time of day.


Asunto(s)
Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/etiología , Adulto , Competencia Clínica , Fatiga/complicaciones , Femenino , Humanos , Trasplante de Hígado/mortalidad , Masculino , Errores Médicos , Persona de Mediana Edad , Inhabilitación Médica , Factores de Tiempo
9.
Am J Transplant ; 10(9): 2154-60, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20636451

RESUMEN

A 43-year-old patient with end-stage renal disease, a hypercoagulable condition and 100% panel reactive antibody was transferred to our institution with loss of hemodialysis access and thrombosis of the superior and inferior vena cava, bilateral iliac and femoral veins. A transhepatic catheter was placed but became infected. Access through a stented subclavian into a dilated azygos vein was established. Desensitization with two cycles of bortezomib was undertaken after anti-CD20 and IVIg were given. A flow-positive, cytotoxic-negative cross-match live-donor kidney at the end of an eight-way multi-institution domino chain became available, with a favorable genotype for this patient with impending total loss of a dialysis option. The patient received three pretransplant plasmapheresis treatments. Intraoperatively, the superior mesenteric vein was the only identifiable patent target for venous drainage. Eculizumab was administered postoperatively in the setting of antibody-mediated rejection and an inability to perform additional plasmapheresis. Creatinine remains normal at 6 months posttransplant and flow cross-match is negative. In this report, we describe the combined use of new agents (bortezomib and eculizumab) and modalities (nontraditional vascular access, splanchnic drainage of graft and domino paired donation) in a patient who would have died without transplantation.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Ácidos Borónicos/uso terapéutico , Fallo Renal Crónico/terapia , Trasplante de Riñón , Donadores Vivos , Inhibidores de Proteasas/uso terapéutico , Pirazinas/uso terapéutico , Obtención de Tejidos y Órganos/métodos , Adulto , Anticuerpos/sangre , Anticuerpos/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antígenos CD20/inmunología , Bortezomib , Catéteres de Permanencia , Creatinina/sangre , Desensibilización Inmunológica/métodos , Drenaje , Quimioterapia Combinada , Femenino , Vena Femoral , Humanos , Vena Ilíaca , Inmunoglobulinas Intravenosas/uso terapéutico , Fallo Renal Crónico/sangre , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/inmunología , Plasmaféresis , Circulación Esplácnica , Terapias en Investigación , Vena Cava Inferior , Vena Cava Superior , Trombosis de la Vena/complicaciones
10.
Am J Transplant ; 9(3): 578-85, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19260837

RESUMEN

Outcomes after heart and lung transplants have improved, and many recipients survive long enough to develop secondary renal failure, yet remain healthy enough to undergo kidney transplantation. We used national data reported to United Network for Organ Sharing (UNOS) to evaluate outcomes of 568 kidney after heart (KAH) and 210 kidney after lung (KAL) transplants performed between 1995 and 2008. Median time to kidney transplant was 100.3 months after heart, and 90.2 months after lung transplant. Renal failure was attributed to calcineurin inhibitor toxicity in most patients. Outcomes were compared with primary kidney recipients using matched controls (MC) to account for donor, recipient and graft characteristics. Although 5-year renal graft survival was lower than primary kidney recipients (61% KAH vs. 73.8% MC, p < 0.001; 62.6% KAL vs. 82.9% MC, p < 0.001), death-censored graft survival was comparable (84.9% KAH vs. 88.2% MC, p = 0.1; 87.6% KAL vs. 91.8% MC, p = 0.6). Furthermore, renal transplantation reduced the risk of death compared with dialysis by 43% for KAH and 54% for KAL recipients. Our findings that renal grafts function well and provide survival benefit in KAH and KAL recipients, but are limited in longevity by the general life expectancy of these recipients, might help inform clinical decision-making and allocation in this population.


Asunto(s)
Trasplante de Corazón , Trasplante de Riñón , Trasplante de Pulmón , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Rechazo de Injerto/etiología , Supervivencia de Injerto , Trasplante de Corazón/estadística & datos numéricos , Humanos , Trasplante de Riñón/estadística & datos numéricos , Trasplante de Pulmón/estadística & datos numéricos , Factores de Tiempo , Trasplante Homólogo
11.
Am J Transplant ; 9(5): 1048-54, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19298449

RESUMEN

Single-center studies have reported equivalent outcomes of kidney allografts recovered with histidine-tryptophan-ketoglutarate (HTK) or University of Wisconsin (UW) solution. However, these studies were likely underpowered and often unadjusted, and multicenter studies have suggested HTK preservation might increase delayed graft function (DGF) and reduce graft survival of renal allografts. To further inform clinical practice, we analyzed the United Network for Organ Sharing (UNOS) database of deceased donor kidney transplants performed from July 2004 to February 2008 to determine if HTK (n = 5728) versus UW (n = 15 898) preservation impacted DGF or death-censored graft survival. On adjusted analyses, HTK preservation had no effect on DGF (odds ratio [OR] 0.99, p = 0.7) but was associated with an increased risk of death-censored graft loss (hazard ratio [HR] 1.20, p = 0.008). The detrimental effect of HTK was a relatively late one, with a strong association between HTK and subsequent graft loss in those surviving beyond 12 months (HR 1.43, p = 0.007). Interestingly, a much stronger effect was seen in African-American recipients (HR 1.55, p = 0.024) than in Caucasian recipients (HR 1.18, p = 0.5). Given recent studies that also demonstrate that HTK preservation reduces liver and pancreas allograft survival, we suggest that the use of HTK for abdominal organ recovery should be reconsidered.


Asunto(s)
Supervivencia de Injerto/efectos de los fármacos , Trasplante de Riñón/inmunología , Soluciones Preservantes de Órganos/farmacología , Adenosina , Adulto , Alopurinol , Población Negra/estadística & datos numéricos , Cadáver , Causas de Muerte , Etnicidad , Femenino , Glucosa/farmacología , Glutatión , Humanos , Insulina , Masculino , Manitol/farmacología , Persona de Mediana Edad , Nefrectomía/métodos , Cloruro de Potasio/farmacología , Procaína/farmacología , Grupos Raciales , Rafinosa , Estudios Retrospectivos , Donantes de Tejidos , Recolección de Tejidos y Órganos/métodos , Trasplante Homólogo/inmunología , Resultado del Tratamiento , Población Blanca/estadística & datos numéricos
12.
Dev Biol ; 213(1): 207-16, 1999 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10452858

RESUMEN

To assess alternative methods for introducing expressing transgenes into the germ line of zebrafish, transgenic fish that express a nuclear-targeted, enhanced, green fluorescent protein (eGFP) gene were produced using both pseudotyped retroviral vector infection and DNA microinjection of embryos. Germ-line transgenic founders were identified and the embryonic progeny of these founders were evaluated for the extent and pattern of eGFP expression. To compare the two modes of transgenesis, both vectors used the Xenopus translational elongation factor 1-alpha enhancer/promoter regulatory cassette. Several transgenic founder fish which transferred eGFP expression to their progeny were identified. The gene expression patterns are described and compared for the two modes of gene transfer. Transient expression of eGFP was detected 1 day after introducing the transgenes via either DNA microinjection or retroviral vector infection. In both cases of gene transfer, transgenic females produced eGFP-positive progeny even before the zygotic genome was turned on. Therefore, GFP was being provided by the oocyte before fertilization. A transgenic female revealed eGFP expression in her ovarian follicles. The qualitative patterns of gene expression in the transgenic progeny embryos after zygotic induction of gene expression were similar and independent of the mode of transgenesis. The appearance of newly synthesized GFP is detectable within 5-7 h after fertilization. The variability of the extent of eGFP expression from transgenic founder to transgenic founder was wider for the DNA-injection transgenics than for the retroviral vector-produced transgenics. The ability to provide expressing germ-line transgenic progeny via retroviral vector infection provides both an alternative mode of transgenesis for zebrafish work and a possible means of easily assessing the insertional mutagenesis frequency of retroviral vector infection of zebrafish embryos. However, because of the transfer of GFP from oocyte to embryo, the stability of GFP may create problems of analysis in embryos which develop as quickly as those of zebrafish.


Asunto(s)
ADN Recombinante/administración & dosificación , ADN Recombinante/genética , Vectores Genéticos , Retroviridae/genética , Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Cartilla de ADN/genética , Femenino , Expresión Génica , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Microinyecciones , Proteínas Recombinantes/genética , Pez Cebra/embriología
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