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4.
Am J Transplant ; 17(8): 2065-2077, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28371308

RESUMEN

Reactivation of BK virus in renal allografts causes a destructive chronic infection. This single-center retrospective cohort study describes the evolution of BK virus allograft nephropathy (BKVAN) from 63 kidneys (from 61 patients) using sequential histopathology (454 biopsies, averaging 7.8 ± 2.6 per kidney) followed for 60.1 mo. Uninfected protocol biopsies formulated time-matched control Banff scores (n = 975). Interstitial inflammation occurred in 73% at diagnosis, correlating with viral histopathology (r = 0.413, p = 0.008) and amplifying early injury with accelerated interstitial fibrosis and tubular atrophy (IF/TA, p = 0.017) by 3 mo. Prodromal simian virus 40 large T antigen (SV40T)-negative inflammation with viremia preceded the histological diagnosis in 23.8%. Persistent subacute injury from viral cytopathic effect was associated with acute tubular necrosis and ongoing interstitial inflammation, culminating in IF/TA in 86.9%. Overall, cellular interstitial infiltration mitigated the intensity of subsequent tubular injury, SV40T, and tissue viral load, assessed by sequential paired histology (p < 0.001). Graft loss was predicted by high-level viremia (hazard ratio [HR] 4.996, 95% CI 2.19-11.396, p < 0.001), deceased donor (HR 3.201, 95% CI 1.149-8.915, p = 0.026), and late acute rejection (HR 3.124, 95% CI 1.037-9.413, p = 0.043). Transplant failure occurred in 38.1%, with uncontrolled infection (58.3%) and SV40T-negative chronic rejection (41.7%) causing losses. BKVAN is characterized by subacute virus-induced tubular injury, inflammation, and progressive nephron destruction. Effective antiviral therapy remains an unmet clinical need.


Asunto(s)
Rechazo de Injerto/patología , Enfermedades Renales/patología , Trasplante de Riñón/efectos adversos , Trasplante de Páncreas/efectos adversos , Infecciones por Polyomavirus/patología , Infecciones Tumorales por Virus/patología , Viremia/patología , Virus BK/aislamiento & purificación , Virus BK/patogenicidad , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Enfermedades Renales/etiología , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Infecciones por Polyomavirus/etiología , Complicaciones Posoperatorias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Trasplante Homólogo , Infecciones Tumorales por Virus/etiología , Carga Viral , Viremia/etiología
5.
Am J Transplant ; 16(9): 2714-23, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27037866

RESUMEN

The association between prolonged cold ischemic time (CIT) and graft and patient outcomes in live donor kidney transplant recipients remains unclear. The aims of this study were to examine the association of CIT with delayed graft function and graft loss in live donor kidney transplant recipients and those who participated in the Australian Paired Kidney Exchange program using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry. Of 3717 live donor transplant recipients between 1997 and 2012 who were followed for a median of 6.6 years (25 977 person-years), 224 (25%) experienced CIT >4-8 h. Donor age was an effect modifier between CIT and graft outcomes. In recipients who received kidneys from older donors aged >50 years, every hour of increase in CIT was associated with adjusted odds of 1.28 (95% confidence interval [CI] 1.07-1.53, p = 0.007) for delayed graft function, whereas CIT >4-8 h was associated with adjusted hazards of 1.93 (95% CI 1.21-3.09, p = 0.006) and 1.91 (95% CI 1.05-3.49, p = 0.035) for overall and death-censored graft loss, respectively, compared with CIT of 1-2 h. Attempts to reduce CIT in live donor kidney transplants involving older donor kidneys may lead to improvement of graft outcomes.


Asunto(s)
Isquemia Fría/efectos adversos , Funcionamiento Retardado del Injerto/etiología , Rechazo de Injerto/etiología , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Donadores Vivos , Adulto , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/diagnóstico , Supervivencia de Injerto , Humanos , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Nueva Zelanda , Pronóstico , Sistema de Registros , Factores de Riesgo
6.
Am J Transplant ; 14(9): 2126-36, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25307039

RESUMEN

The aim of this study was to investigate the role of infiltrating macrophages in renal allograft fibrosis. Forty-six protocol renal allograft biopsies obtained 1 year after transplantation were stained with Sirius red to quantify fibrosis and double stained with CD68 and CD206 to identify the proportion of alternatively activated (M2) macrophages. Biopsies were analyzed for gene expression by microarray, which was correlated with macrophage infiltration and the severity of fibrosis. The number of infiltrating CD68+ cells strongly correlated with the percentage of interstitial fibrosis (r = 0.73, p < 0.0001). Macrophage infiltration at 1 year correlated with renal dysfunction at 1, 12 and 36 months posttransplant (estimated GFR low vs. high: 1 month 78 ± 26 vs. 54 ± 19 mL/min, p < 0.01; 12 months 87 ± 29 vs. 64 ± 19 mL/min, p < 0.05; 36 months 88 ± 33 vs. 60 ± 24 mL/min, p < 0.05). Ninety-two percent of infiltrating macrophages exhibited an M2 phenotype with CD68+ CD206+ dual staining. Gene microarrays demonstrated an alloimmune response with up-regulation of interferon-γ-response genes despite the lack of rejection or inflammatory infiltrate. Consistent with this was the presence of CXCL10 in proximal tubular cells at 3 months. This suggests that M2 macrophage proliferation, or infiltration, was associated with subclinical alloimmune inflammation, tubular injury and progression of fibrosis.


Asunto(s)
Fibrosis/fisiopatología , Trasplante de Riñón , Macrófagos/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Am J Transplant ; 14(4): 923-35, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24612855

RESUMEN

A major barrier to meeting the needs for organ transplantation is family refusal to give consent. This study aimed to describe the perspectives of donor families on deceased donation. We conducted a systematic review and thematic synthesis of qualitative studies. Electronic databases were searched to September 2012. From 34 studies involving 1035 participants, we identified seven themes: comprehension of sudden death (accepting finality of life, ambiguity of brain death); finding meaning in donation (altruism, letting the donor live on, fulfilling a moral obligation, easing grief); fear and suspicion (financial motivations, unwanted responsibility for death, medical mistrust); decisional conflict (pressured decision making, family consensus, internal dissonance, religious beliefs); vulnerability (valuing sensitivity and rapport, overwhelmed and disempowered); respecting the donor (honoring the donor's wishes, preserving body integrity) and needing closure (acknowledgment, regret over refusal, unresolved decisional uncertainty, feeling dismissed). Bereaved families report uncertainty about death and the donation process, emotional and cognitive burden and decisional dissonance, but can derive emotional benefit from the "lifesaving" act of donation. Strategies are needed to help families understand death in the context of donation, address anxieties about organ procurement, foster trust in the donation process, resolve insecurities in decision making and gain a sense of closure.


Asunto(s)
Toma de Decisiones , Familia/psicología , Investigación Cualitativa , Obtención de Tejidos y Órganos/tendencias , Altruismo , Muerte , Humanos , Relaciones Interpersonales , Motivación , Trasplante de Órganos , Pronóstico
8.
Am J Transplant ; 13(10): 2645-52, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24034231

RESUMEN

Transplantation of any biological material from a donor to a host will carry some inherent risk of disease transmission. Our aims were to summarize the totality of the published evidence about donor cancer transmission among kidney transplant recipients and to determine the cancer-specific survival of these patients. We systematically reviewed all case reports, case series and registry studies that described the outcomes of kidney transplant recipients with donor cancer transmission published to December 2012. A total of 69 studies with 104 donor-transmitted cancer cases were identified. The most common transmitted cancer types were renal cancer (n = 20, 19%), followed by melanoma (n = 18, 17%), lymphoma (n = 15, 14%) and lung cancer (n = 9, 9%). Patients with melanoma and lung cancers had the worst prognosis, with less than 50% of recipients surviving after 24 months from transplantation. Recipients with transmitted renal cancers had the best outcomes, with over 70% of recipients surviving for at least 24 months after transplantation. Overall, the risk of donor transmission of cancer appears low, but there is a high likelihood of reporting bias. Our findings support the current recommendations for rejecting organs from donors with a history of melanoma and lung cancer, but suggest that the use of donor kidneys with a history of small, incidental renal cell cancer may be reasonable.


Asunto(s)
Neoplasias Renales/etiología , Trasplante de Riñón/efectos adversos , Donantes de Tejidos , Humanos , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Pronóstico , Tasa de Supervivencia
9.
Intern Med J ; 43(11): 1183-90, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24007325

RESUMEN

BACKGROUND: Voluntary donations of peripheral blood stem cells after administration of filgrastim (granulocyte-colony stimulating factor, G-CSF) are undertaken throughout the world by healthy individuals, but the short-, medium- and long-term adverse events during and after donation are not fully understood. AIMS: We document the experience of donors of peripheral blood stem cells mobilised by G-CSF at Australian Bone Marrow Donor Registry collection centres. METHODS: When the Australian Bone Marrow Donor Registry commenced collecting mobilised peripheral blood stem cells, based on data used for registration of G-CSF, all adverse reactions in donors were documented prospectively to determine the rate and severity of events. A total of 512 consecutive first-time donors assessed between July 2001 and March 2010 were included in this study. RESULTS: The median age at work-up was 40 years and 71% of donors were male. A large proportion of donors (91%) experienced bone pain during administration of G-CSF, and in fewer numbers headache (61%) and fatigue (61%). Bone pain was associated with a body mass index of overweight/obese (P = 0.03). Headache (P = 0.03), muscle pain (P = 0.03) and fatigue (P = 0.001) were all significantly associated with female sex. More than a quarter (28%) of donations involved a range of complications at collection. CONCLUSION: The incidence of short- and medium-term symptoms and events observed provide support for the information provided to unrelated donors at counselling. Follow up of the consequences of unrelated voluntary donation remains important to provide accurate and relevant information to prospective donors.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Movilización de Célula Madre Hematopoyética/métodos , Donante no Emparentado , Adulto , Australia/epidemiología , Eliminación de Componentes Sanguíneos/psicología , Femenino , Filgrastim , Estudios de Seguimiento , Movilización de Célula Madre Hematopoyética/psicología , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/psicología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Recombinantes/administración & dosificación , Donante no Emparentado/psicología , Adulto Joven
10.
Am J Transplant ; 13(11): 2912-23, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24020905

RESUMEN

The assessment of living kidney donors presents unique ethical challenges and complex psychosocial implications. This study aimed to ascertain the perspectives of transplant nephrologists and surgeons on living kidney donor assessment. Semi-structured, face-to-face interviews were conducted with 110 transplant nephrologists and surgeons from 43 transplant units in 12 countries from Europe, Australasia and North America. The challenge of defining acceptable risk to the donor was central to five themes identified: burden of responsibility (personal accountability, policing morality, democratic decision making, meeting legal obligations, optimizing outcomes and innovation, relinquished control); medical protectiveness (prognostic uncertainty, skepticism of donor risk perception, avoidance of undue coercion, concerns for dubious motivations and coercion, safeguard donor well-being, ethical information disclosure); respecting donor autonomy (facilitate informed-decision making, concede to donor risk acceptance, benefit of the doubt, donor mandate to maintain health, acceptable altruism); driving ideologies (preserving equity, championing living donation, cognizance of anti-paternalism) and contextual pressures (evolving donor demographic, resource limitations). Living kidney donor assessment involves complex interactions between safeguarding the donors' welfare and respecting their autonomy. In our opinion, authoritative and well-described transplant unit, hospital and public policy positions that make explicit the considerations that are often implicit may reduce the uncertainty within which living donors are assessed today.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones , Cirugía General , Trasplante de Riñón , Donadores Vivos/psicología , Nefrología , Médicos/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Médicos/ética , Investigación Cualitativa , Obtención de Tejidos y Órganos/ética , Obtención de Tejidos y Órganos/legislación & jurisprudencia
11.
Clin Transplant ; 27(5): E571-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23952788

RESUMEN

Screening for polyoma BK virus (BK) using nucleic testing (NAT) is recommended for kidney and kidney-pancreas transplant recipients, but the performance characteristics of quantitative BK NAT at different thresholds of plasma BK viral loads are unclear. We aim to evaluate the diagnostic accuracy of quantitative BK NAT as an add-on test to qualitative polyoma NAT for the diagnosis of BK virus-associated nephropathy (BKVAN) in kidney and kidney transplant recipients. We calculated the test sensitivity, specificity, and predictive values at the different thresholds of plasma BK viral load for BKVAN. At the recommended threshold of >1 × 10(3) serum BK copies/mL serum for test positivity, the sensitivity for BKVAN was 92.9% (95% confidence intervals [CI]: 66.1-99.8) and specificity 79.1% (95%: CI 67.4-88.1), with corresponding positive and negative predictive values of 42.0% (95% CI: 24.8-57.7%) and 98.6% (95% CI: 98.3-99.9%), respectively. The overall area under curve for the quantitative BK NAT was 0.92 (95% CI: 0.85-0.97). Quantitative BK NAT displays properties of high sensitivity and specificity that are fit for purpose as an add-on test to qualitative polyomavirus NAT for kidney and kidney-pancreas transplant recipients at risk of BKVAN.


Asunto(s)
Virus BK/genética , ADN Viral/genética , Enfermedades Renales/diagnóstico , Trasplante de Riñón , Trasplante de Páncreas , Infecciones por Polyomavirus/diagnóstico , Infecciones Tumorales por Virus/diagnóstico , Adulto , Virus BK/aislamiento & purificación , Estudios Transversales , ADN Viral/sangre , Femenino , Estudios de Seguimiento , Humanos , Enfermedades Renales/sangre , Enfermedades Renales/virología , Masculino , Persona de Mediana Edad , Enfermedades Pancreáticas/sangre , Enfermedades Pancreáticas/diagnóstico , Enfermedades Pancreáticas/virología , Infecciones por Polyomavirus/sangre , Infecciones por Polyomavirus/virología , Pronóstico , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones Tumorales por Virus/sangre , Infecciones Tumorales por Virus/virología
12.
Am J Transplant ; 13(6): 1390-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23648238

RESUMEN

Qualitative studies remain relatively uncommon in the transplant literature but are an important approach contributing unique strengths in some areas of research. With the increased focus on patient-centered research and decision-making, it is timely to review qualitative research in the context of transplantation. While quantitative research addresses questions about the effectiveness of interventions or associations between risk factors and outcomes, qualitative research has an equal and complementary role in providing understanding about people's behaviors, attitudes, and values. Qualitative research has provided insights into some of the important but elusive questions in transplantation, including the sources of barriers to organ donation and inequities in access to transplantation, nonadherence to immunosuppressive regimens, and complex psychosocial outcomes. This review highlights recent contributions of qualitative research to transplantation practice and policy, and identifies key principles to guide qualitative research appraisal.


Asunto(s)
Trasplante de Órganos/normas , Políticas , Investigación Cualitativa , Humanos
13.
Plant Dis ; 97(6): 708-719, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30722585

RESUMEN

Pseudomonas syringae pv. actinidiae, the causal agent of bacterial canker of kiwifruit, was detected for the first time in New Zealand in November 2010. Only in Bay of Plenty, one of the four regions where this pathogen had been detected, did symptoms evolve beyond leaf spots, resulting in cane die-back, wilting of canes, and canker, sometimes leading to death of the vine. Molecular analysis (cts haplotype and BOX-polymerase chain reaction [PCR] electrophoretic pattern) of strains isolated from different regions of New Zealand revealed that two biovars could be distinguished. They have been called biovar 3 and biovar 4 to differentiate them from strains from Japan (biovar 1) or Korea (biovar 2), which have a different cts haplotype or a different BOX-PCR pattern. Biovars 3 and 4 displayed different degrees of virulence, as measured by their ability to cause leaf spots on young, potted kiwifruit plants. Biovar 3, which has also been present in Italy since 2008 and in France, was found in the Bay of Plenty, where cane diebacks were observed. In contrast, no symptoms other than leaf spots have been observed in orchards where strains of biovar 4 have been isolated. We report the distribution and the disease progression of biovars 3 and 4 in New Zealand.

15.
Phytopathology ; 102(11): 1034-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22877312

RESUMEN

ABSTRACT Pseudomonas syringae pv. actinidiae, the causal agent of canker in kiwifruit (Actinidia spp.) vines, was first detected in Japan in 1984, followed by detections in Korea and Italy in the early 1990s. Isolates causing more severe disease symptoms have recently been detected in several countries with a wide global distribution, including Italy, New Zealand, and China. In order to characterize P. syringae pv. actinidiae populations globally, a representative set of 40 isolates from New Zealand, Italy, Japan, South Korea, Australia, and Chile were selected for extensive genetic analysis. Multilocus sequence analysis (MLSA) of housekeeping, type III effector and phytotoxin genes was used to elucidate the phylogenetic relationships between P. syringae pv. actinidiae isolates worldwide. Four additional isolates, including one from China, for which shotgun sequence of the whole genome was available, were included in phylogenetic analyses. It is shown that at least four P. syringae pv. actinidiae MLSA groups are present globally, and that marker sets with differing evolutionary trajectories (conserved housekeeping and rapidly evolving effector genes) readily differentiate all four groups. The MLSA group designated here as Psa3 is the strain causing secondary symptoms such as formation of cankers, production of exudates, and cane and shoot dieback on some kiwifruit orchards in Italy and New Zealand. It is shown that isolates from Chile also belong to this MLSA group. MLSA group Psa4, detected in isolates collected in New Zealand and Australia, has not been previously described. P. syringae pv. actinidiae has an extensive global distribution yet the isolates causing widespread losses to the kiwifruit industry can all be traced to a single MLSA group, Psa3.


Asunto(s)
Actinidia/microbiología , Enfermedades de las Plantas/microbiología , Pseudomonas syringae/genética , Asia , Australasia , ADN Bacteriano/química , ADN Bacteriano/genética , Europa (Continente) , Evolución Molecular , Frutas/microbiología , Genes Bacterianos/genética , Familia de Multigenes , Tipificación de Secuencias Multilocus , Filogenia , Pseudomonas syringae/clasificación , Pseudomonas syringae/aislamiento & purificación , América del Sur
17.
Int J Organ Transplant Med ; 3(1): 18-25, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-25013619

RESUMEN

BACKGROUND: Invasive fungal infection (IFI) is a leading cause of infection-related mortality among kidney allograft recipients.  OBJECTIVE: To estimate the incidence and etiology of systemic fungal infection in renal allograft recipients in Sydney transplant facility. METHODS: 471 kidney recipients, transplanted between 2000 and 2010 at the Westmead Hospital renal transplantation center, Sydney, Australia, were retrospectively surveyed. RESULTS: IFI developed in 10 (2.1%) of 471 patients. With a mean±SD new kidney transplants per year of 42.9±13, the mean±SD incidence of IFI was 0.9±0.6 for each year of transplantation. 4 patients had received kidneys from living donors and 7 from cadavers with a mean±SD age of 50.5±14 years. The mean time to IFI was 33 months after transplantation with majority within the first 2 years. Cryptococcus neoformans was responsible for 50% of episodes (n=5) followed by Aspergillus fumigatus (n=3), and Pseudallescheria boydii (n=3); there was a single case of mucurmycosis. Lungs (n=5) followed by meninges (n=4) and skin (n=3) were the most commonly involved sites. CONCLUSION: IFI remains a major concern in renal transplantation. A high index of suspicion is required for early diagnosis and treatment to reduce the mortality. In this regard, appropriate diagnostic tests are necessary, particularly for C. neoformans.

18.
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
20.
Am J Transplant ; 11(8): 1570-5, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21797971

RESUMEN

Protocol renal allograft biopsies at fixed time points from transplantation have aided research and provided insights into the pathogenesis of early and late allograft injury. Their role is evolving from research to a clinical management tool needed to detect subclinical pathology requiring treatment adjustment. They frequently reveal unexpected findings and influence therapy in the majority of patients. Detection of subclinical rejection (SCR) remains important despite declining prevalence with triple therapy, the evidence favors treatment, if found. Surveillance biopsies in steroid avoidance and calcineurin inhibitor (CNI) withdrawal programs provide an important safety net against the increased rates of late acute and SCR. Individualization of therapy in high-risk patients and safe reduction of immunosuppression in standard risk individuals becomes possible. Other potentially reversible chronic pathologies that may be detected, include chronic T-cell or antibody-mediated rejection, recurrent disease, BK virus-associated nephropathy, interstitial fibrosis and tubular atrophy and CNI nephrotoxicity, allowing modifications of therapy to limit ongoing graft injury. Biopsy is safe and inexpensive compared with costs of earlier graft failure and return to dialysis. This review summarizes current evidence on use of surveillance histology for the clinical practice of renal transplantation.


Asunto(s)
Biopsia , Trasplante de Riñón , Vigilancia de la Población , Humanos , Enfermedades Renales/patología , Enfermedades Renales/cirugía
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