Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Liver Transpl ; 19(11): 1214-23, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23907778

RESUMEN

The impact of ischemia/reperfusion injury in the setting of transplantation for hepatocellular carcinoma (HCC) has not been thoroughly investigated. The present study examined data from the Scientific Registry of Transplant Recipients for all recipients of deceased donor liver transplants performed between January 1, 1995 and October 31, 2011. In a multivariate Cox analysis, significant predictors of patient survival included the following: HCC diagnosis (P < 0.01), donation after cardiac death (DCD) allograft (P < 0.001), hepatitis C virus-positive status (P < 0.01), recipient age (P < 0.01), donor age (P < 0.001), Model for End-Stage Liver Disease score (P < 0.001), recipient race, and an alpha-fetoprotein level > 400 ng/mL at the time of transplantation. In order to test whether the decreased survival seen for HCC recipients of DCD grafts was more than would be expected because of the inferior nature of DCD grafts and the diagnosis of HCC, a DCD allograft/HCC diagnosis interaction term was created to look for potentiation of effect. In a multivariate analysis adjusted for all other covariates, this interaction term was statistically significant (P = 0.049) and confirmed that there was potentiation of inferior survival with the use of DCD allografts in recipients with HCC. In conclusion, patient survival and graft survival were inferior for HCC recipients of DCD allografts versus recipients of donation after brain death allografts. This potentiation of effect of inferior survival remained even after adjustments for the inherent inferiority observed in DCD allografts as well as other known risk factors. It is hypothesized that this difference could reflect an increased rate of recurrence of HCC.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Adulto , Anciano , Aloinjertos , Carcinoma Hepatocelular/mortalidad , Muerte , Femenino , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Donantes de Tejidos
2.
Liver Transpl ; 19(11): 1236-44, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23913790

RESUMEN

Liver donor characteristics have a significant impact on graft quality and, in turn, recipient outcomes. In this study, we examined deceased liver donor characteristics and donor risk index (DRI) trends in Canada over the past decade. Data were extracted from the Canadian Organ Replacement Register and Transplant Québec for the decade (2000-2010). Trends in the DRI and donor characteristics, including age, race, height, cause of death (COD), location, cold ischemia time (CIT), and type of donation, were examined. In all, 3746 transplants using deceased liver donors were analyzed. The age of donors, the proportion of black donors, the proportion of cerebrovascular accidents as the COD, and the proportion of donation after cardiac death (DCD) donors all increased over the aforementioned time period. The proportion of transplants classified geographically as local increased, and the CIT for donor livers decreased. Although many of the parameters adversely affecting the DRI increased over the study period, the DRI showed only a slightly significant trend of increasing. The increase in these parameters was counteracted by a decrease in modifiable risk factors such as the CIT and distance traveled. The 5-year recipient survival rate increased from 71.43% (1999-2001) to 75.50% (2005-2007); however, this trend was not significant. Although there was an increase in the use of older and DCD organs, recipient survival was not compromised. In conclusion, demographic trends for liver donors in Canada suggest an increase in the use of higher risk donors. However, the overall graft quality has been not compromised because of a decreasing trend for the CIT and an increase in local transplants. Better coordination and allocation practices in liver transplantation across Canada have minimized the risk of graft failure and resulted in good recipient outcomes.


Asunto(s)
Trasplante de Hígado , Donantes de Tejidos , Adulto , Anciano , Canadá , Causas de Muerte , Isquemia Fría , Supervivencia de Injerto , Humanos , Trasplante de Hígado/mortalidad , Persona de Mediana Edad
3.
J Surg Res ; 185(2): 877-82, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23953787

RESUMEN

BACKGROUND: As the survival of patients after liver transplantation (LT) improves, the requirement of liver retransplantation (reLT) for late graft failure has grown. Although some have reported that the short-term outcome of late reLT was comparable with that of early reLT, it remains unknown whether long-term survival of late reLT is inferior to that of early reLT patients. MATERIALS AND METHODS: We reviewed early (<6 mo after primary LT) and late (≥6 mo after primary LT) reLT cases performed between January 2000 and December 2010. RESULTS: Sixteen early and 32 late reLT cases were analyzed. There was no significant difference regarding the number of units of red blood cells transfused during the transplantation between the groups, whereas operative time was significantly longer in the late reLT cases. Graft loss within 3 mo after early and late reLT was 18.6% and 15.6%, respectively. Patient and graft survival rates after 1, 3, 5, and 10 y in the late reLT group were 80.6%, 73.3%, 73.3%, and 67.7% and 80.7%, 69.1%, 63.3%, and 54.3%, respectively, whereas those in the early reLT group were 75.0%, 75.0%, 64.3%, and 64.3% and 81.3%, 75.0%, 64.3%, and 32.1%, respectively. There was no significant difference in patient or graft survival rates between the groups (P = 0.91 and 0.91, respectively). CONCLUSIONS: Acceptable short- and long-term survival were provided in early and late reLT. The time between the primary LT and reLT does not seem to play significant role in the prognosis of reLT in the long term.


Asunto(s)
Funcionamiento Retardado del Injerto/mortalidad , Supervivencia de Injerto , Hepatopatías/mortalidad , Trasplante de Hígado/mortalidad , Complicaciones Posoperatorias/mortalidad , Reoperación/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Funcionamiento Retardado del Injerto/cirugía , Femenino , Humanos , Hepatopatías/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Factores de Tiempo , Donantes de Tejidos , Adulto Joven
4.
J Surg Res ; 176(2): 614-20, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22221603

RESUMEN

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) is a central mediator in the hepatic response to ischemia/reperfusion. Short hairpin RNA (shRNA) has been proven to be an effective means of harnessing the RNA interference pathway in mammalian cells. In the current study, we investigated whether silencing TNF-α gene with shRNA can prevent liver ischemic reperfusion injury (IRI). METHODS: Male BalB/c mice were randomized to TNF-α shRNA, scramble shRNA, or sham operation groups. TNF-α shRNA and scramble shRNA groups were injected 48 h before inducing IRI. IRI was induced via microaneurysm clamps applied to the left hepatic artery and portal vein. Six hours after reperfusion, IRI injury was examined by serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), liver histopathology, MPO, and MDA level, as well as by relative quantities of TNF-α mRNA. RESULTS: TNF-α expression induced by ischemia reperfusion in the liver was significantly suppressed after treatment with TNF-α shRNA compared with the group treated with scramble shRNA (P < 0.001). Mice treated with TNF-α shRNA showed lower peak values of AST and ALT than scramble shRNA treated mice (P < 0.001). On histopathologic slides, mice treated with TNF-α shRNA had significantly less ischemia/reperfusion injury based on Suzuki score than the scramble shRNA group, 3.57 ± 2.30 and 8.83 ± 0.98 respectively (P < 0.001), while the sham group was not significantly different from the TNF-alpha shRNA group, 0 ± 0 and 3.57 ± 2.30, respectively (P = 0.075). Liver tissue MDA levels were significantly lower in mice treated with TNF-α shRNA as compared with the group treated with scramble shRNA (P < 0.01). Immunohistochemical staining for MPO was significantly lower in mice treated with TNF-α shRNA compared with the group treated with shRNA (compared with treated with scramble shRNA group.) CONCLUSIONS: Liver IRI can be minimized through gene silencing of TNF-α. This may represent a novel therapy in the setting of transplantation and in other conditions associated with IRI of the liver.


Asunto(s)
Terapia Genética/métodos , Hígado/fisiología , ARN Interferente Pequeño/farmacología , Daño por Reperfusión/genética , Daño por Reperfusión/terapia , Factor de Necrosis Tumoral alfa/genética , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Regulación hacia Abajo/genética , Hígado/patología , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos BALB C , Peroxidasa/metabolismo , ARN Interferente Pequeño/genética , Daño por Reperfusión/patología
5.
Nat Med ; 11(12): 1295-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16311604

RESUMEN

We transplanted kidneys from alpha1,3-galactosyltransferase knockout (GalT-KO) pigs into six baboons using two different immunosuppressive regimens, but most of the baboons died from severe acute humoral xenograft rejection. Circulating induced antibodies to non-Gal antigens were markedly elevated at rejection, which mediated strong complement-dependent cytotoxicity against GalT-KO porcine target cells. These data suggest that antibodies to non-Gal antigens will present an additional barrier to transplantation of organs from GalT-KO pigs to humans.


Asunto(s)
Animales Modificados Genéticamente , Rechazo de Injerto/inmunología , Tolerancia Inmunológica/inmunología , Trasplante de Riñón/inmunología , Trasplante Heterólogo/mortalidad , Trasplante Heterólogo/métodos , Animales , Anticuerpos/sangre , Galactosiltransferasas/genética , Galactosiltransferasas/inmunología , Terapia de Inmunosupresión/métodos , Papio , Sus scrofa/genética , Linfocitos T/inmunología , Trasplante Heterólogo/inmunología
6.
Can J Gastroenterol ; 26(9): 607-10, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22993731

RESUMEN

BACKGROUND: Previous studies have shown a higher incidence of biliary complications following donation after cardiac death (DCD) liver transplantation compared with donation after brain death (DBD) liver transplantation. The endoscopic management of ischemic type biliary strictures in patients who have undergone DCD liver transplants needs to be characterized further. METHODS: A retrospective institutional review of all patients who underwent DCD liver transplant from January 2006 to September 2011 was performed. These patients were compared with all patients who underwent DBD liver transplantation in the same time period. A descriptive analysis of all DCD patients who developed biliary complications and their subsequent endoscopic management was also performed. RESULTS: Of the 36 patients who received DCD liver transplants, 25% developed biliary complications compared with 13% of patients who received DBD liver transplants (P=0.062). All DCD allograft recipients who developed biliary complications became symptomatic within three months of transplantation. Ischemic type biliary strictures in DCD allograft recipients included disseminated biliary strictures in two patients, biliary strictures of the hepatic duct bifurcation in three patients and biliary strictures of the donor common hepatic duct in three patients. CONCLUSIONS: There was a trend toward increasing incidence of total biliary complications in recipients of DCD liver allografts compared with those receiving DBD livers, and the rate of diffuse ischemic cholangiopathy was significantly higher. Focal ischemic type biliary strictures can be treated effectively in DCD liver transplant recipients with favourable results. Diffuse ischemic type biliary strictures in DCD liver transplant recipients ultimately requires retransplantation.


Asunto(s)
Enfermedades de las Vías Biliares/cirugía , Causas de Muerte , Selección de Donante , Enfermedad Hepática en Estado Terminal/cirugía , Endoscopía , Trasplante de Hígado/efectos adversos , Adulto , Enfermedades de las Vías Biliares/epidemiología , Enfermedades de las Vías Biliares/patología , Muerte Encefálica , Enfermedad Hepática en Estado Terminal/mortalidad , Enfermedad Hepática en Estado Terminal/patología , Femenino , Paro Cardíaco , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
7.
Hepatobiliary Pancreat Dis Int ; 11(4): 372-6, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22893463

RESUMEN

BACKGROUND: An updated definition of early allograft dysfunction (EAD) was recently validated in a multicenter study of 300 deceased donor liver transplant recipients. This analysis did not differentiate between donation after brain death (DBD) and donation after cardiac death (DCD) allograft recipients. METHODS: We reviewed our prospectively entered database for all DBD (n=377) and DCD (n=38) liver transplantations between January 1, 2006 and October 30, 2011. The incidence of EAD as well as its ability to predict graft failure and survival was compared between DBD and DCD groups. RESULTS: EAD was a valid predictor of both graft and patient survival at six months in DBD allograft recipients, but in DCD allograft recipients there was no significant difference in the rate of graft failure in those with EAD (11.5%) compared with those without EAD (16.7%) (P=0.664) or in the rate of death in recipients with EAD (3.8%) compared with those without EAD (8.3%) (P=0.565). The graft failure rate in the first 6 months in those with international normalized ratio ≥1.6 on day 7 who received a DCD allograft was 37.5% compared with 6.7% for those with international normalized ratio <1.6 on day 7 (P=0.022). CONCLUSIONS: The recently validated definition of EAD is a valid predictor of patient and graft survival in recipients of DBD allografts. On initial assessment, it does not appear to be a useful predictor of patient and graft survival in recipients of DCD allografts, however a study with a larger sample size of DCD allografts is needed to confirm these findings. The high ALT/AST levels in most recipients of DCD livers as well as the predisposition to biliary complications and early cholestasis make these parameters as poor predictors of graft failure. An alternative definition of EAD that gives greater weight to the INR on day 7 may be more relevant in this population.


Asunto(s)
Muerte Encefálica , Trasplante de Hígado/efectos adversos , Disfunción Primaria del Injerto/etiología , Donantes de Tejidos , Adulto , Enfermedades de las Vías Biliares/etiología , Colestasis/etiología , Femenino , Supervivencia de Injerto , Humanos , Incidencia , Relación Normalizada Internacional , Trasplante de Hígado/mortalidad , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ontario , Valor Predictivo de las Pruebas , Disfunción Primaria del Injerto/clasificación , Disfunción Primaria del Injerto/diagnóstico , Disfunción Primaria del Injerto/mortalidad , Medición de Riesgo , Factores de Riesgo , Terminología como Asunto , Factores de Tiempo , Resultado del Tratamiento
9.
Can J Surg ; 55(5): 322-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22992421

RESUMEN

BACKGROUND: Few studies have examined perioperative outcomes in nonagenarians undergoing abdominal surgery, and fewer have reported on 1-year mortality. Our objectives were to determine the outcomes of abdominal surgery in nonagenarians and to assess the performance of Physiologic and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) and Portsmouth-POSSUM (p- POSSUM) as predictors of mortality. METHODS: We conducted a retrospective chart review of all patients 90 years and older who underwent abdominal surgery between 2000 and 2007 at a tertiary care hospital. RESULTS: We included 145 patients (median age 91, range 90-101 yr). The most common diagnoses were colorectal cancer (19.3%) and hernias (19.3%), and the most common procedures were bowel resection with anastomosis (25.5%) and hernia repair (18.6%). Overall in-hospital mortality was 15.2% (20.8% in the emergent group and 9.6% in the elective group; p = 0.06). The 1-year mortality (49.1% v. 27.8%; p = 0.016), complication (81.9% v. 61.6%; p = 0.007) and intensive care unit admission rates (44.4% v. 11.0%; p < 0.001) were significantly higher among emergent than elective surgical patients. The operative indications and procedures associated with the highest in-hospital mortality were large bowel obstruction (42.3%) and bowel resection with anastomosis (27.0%). Both the POSSUM and p-POSSUM scoring systems significantly overpredicted mortality, particularly in higher risk groups. CONCLUSION: Nonagenarians undergoing abdominal surgery have substantial operative morbidity and mortality, particularly in emergent surgical cases. Nearly 50% of patients who undergo emergency procedures die within 1 year after surgery. The POSSUM and p-POSSUM scoring systems were not reliable predictors of in-hospital mortality.


Asunto(s)
Abdomen/cirugía , Procedimientos Quirúrgicos Electivos/mortalidad , Tratamiento de Urgencia/mortalidad , Mortalidad Hospitalaria , Anciano de 80 o más Años , Femenino , Mortalidad Hospitalaria/tendencias , Humanos , Londres , Masculino , Registros Médicos , Valor Predictivo de las Pruebas , Estudios Retrospectivos
10.
Curr Pharm Teach Learn ; 14(3): 253-257, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35307082

RESUMEN

INTRODUCTION: Medicinal chemistry is a polarizing subject for pharmacy students where, if not embraced, future pharmacists may be limited in their role as drug experts. An understanding of medicinal chemistry and its structure-activity relationships creates a strong foundation upon which our knowledge of pharmacotherapy is built. PERSPECTIVE: As the field of pharmacy has shifted to an increasingly clinical role, with an emphasis on patient care as a member of the interprofessional team, pharmacy has also seen an increase in postgraduate training, specifically residencies and fellowships. Pharmacy students noting this trend may depreciate medicinal chemistry early in the curriculum and place more focus on therapeutics and clinical rotations. However, forgoing the fundamental understanding of medicinal chemistry may hinder pharmacy students' current breadth and understanding, and the ability to rationalize future developments in their practice. Medicinal chemistry empowers pharmacists with the ability to reason through medications' impact versus simply memorizing their actions. Pharmacists play a unique role as drug experts, with advanced problem-solving and critical thinking skills that set them apart from drug references and search engines. IMPLICATIONS: As the field moves towards pharmacists as a member of the clinical team, the faculty should integrate medicinal chemistry throughout the doctor of pharmacy curricula. Faculty without this ability for a curriculum change should consider integration in their content. The field of pharmacy must take care to not allow clinical knowledge to significantly overshadow the importance of medicinal chemistry or run the risk of saturating the field with underprepared pharmacists.


Asunto(s)
Educación en Farmacia , Estudiantes de Farmacia , Química Farmacéutica/educación , Curriculum , Humanos , Solución de Problemas
11.
Ann Hepatol ; 10(4): 477-81, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21911888

RESUMEN

INTRODUCTION: Liver transplantation is a highly effective treatment for end-stage liver disease. However, there is debate over the practice of liver transplantation in older recipients (age ≥ 60 years) given the relative shortage of donor grafts, worse post-transplantation survival, and concern that that older patients may utilize excess resources postoperatively, thus threatening the economic feasibility of the procedure. AIM: To determine if patients ≥ 60 years of age utilize more health resources following liver transplantation compared with younger patients. MATERIAL AND METHODS: Consecutive adult patients who underwent primary liver transplantation (n = 208) at a single center were studied over a 2.5-year period. Data were collected on clinico-demographic characteristics and resource utilization. Descriptive statistics, including means, standard deviations, or frequencies were obtained for baseline variables. Patients were stratified into 2 groups: age ≥ 60 years (n = 51) and < 60 years (n = 157). The Chi-Square Test, Mantel-Haenszel Test, 2-sample test and odds ratios were calculated to ascertain associations between age and resource utilization parameters. Regression analyses were adjusted for model for end-stage liver disease score, location before surgery, diabetes mellitus, donor age, cold ischemia time, albumin, and diagnosis of hepatitis C. RESULTS: Recipients ≥ 60 years of age have similar lengths of hospitalization, re-operative rates, need for consultative services and readmission rates following liver transplantation, but have longer lengths of stay in the intensive care (hazard ratio 1.97, p = 0.03). CONCLUSION: Overall, liver transplant recipients ≥ 60 years of age utilize comparable resources following LT vs. younger recipients. Our findings have implications on cost-containment policies for liver transplantation.


Asunto(s)
Atención a la Salud/estadística & datos numéricos , Recursos en Salud/estadística & datos numéricos , Trasplante de Hígado , Adulto , Factores de Edad , Anciano , Distribución de Chi-Cuadrado , Cuidados Críticos/estadística & datos numéricos , Atención a la Salud/economía , Femenino , Recursos en Salud/economía , Humanos , Tiempo de Internación , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/economía , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Ontario , Readmisión del Paciente , Derivación y Consulta/estadística & datos numéricos , Análisis de Regresión , Reoperación , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
12.
Can J Anaesth ; 58(7): 599-605, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21538211

RESUMEN

PURPOSE: The aim of this study was to explore donor and recipient outcomes from organ donation after cardiac death (DCD) in Ontario and to examine the impact of DCD on deceased donation rates in Ontario since its implementation. METHODS: Donor data were obtained from the Trillium Gift of Life Network (TGLN) TOTAL database from June 1, 2006 until May 31, 2009. All DCDs were tracked, including unsuccessful DCD attempts during that time. For the first 36 months after DCD implementation, all Ontario solid organ transplant programs that utilized organs from DCD provided clinical outcome data at one year. Total DCD activity until December 1, 2010 was also tracked. In addition, we compared organ donation and DCD rates across all Canadian jurisdictions and the USA. RESULTS: For the first 36 months of DCD activity in Ontario, June 1, 2006 to May 31, 2009, there were 67 successful DCDs out of 87 attempted DCDs in 18 Ontario hospitals, resulting in 128 kidney, 41 liver, and 21 lung transplants. The one-year kidney patient and death-censored allograft survivals were 96 and 97%, respectively. Mean (SD) creatinine at 12 months was 150 (108) µmol·L(-1). In 26 (20%) extended criteria donors (ECD-DCD), the one-year creatinine was 206 (158) µmol·L(-1) vs 137 (80) µmol·L(-1) in 102 standard criteria donors (SCD-DCD) (P = 0.002). The one-year liver and lung allograft survivals were 78% and 70%, respectively. Since its implementation four and a half years ago, DCD has accounted for 10.9% of deceased donor activity in Ontario. In 2009, Ontario had a record number of organ donors. Of the 221 deceased donors, 37 (17%) donors were DCD. By December 1, 2010 there were 121 DCD Ontario donors resulting in > 300 solid organ transplants and accounting for 90% of all DCD activity in the country. CONCLUSION: The rapid update of DCD in Ontario can be attributed to strong proponents in the critical care and transplantation communities with continued support from Trillium Gift of Life Network (TGLN). Ontario is the only province to demonstrate growth in deceased donor rates over the last decade (25% over the last four years), which can be attributed primarily to the success of its DCD activity.


Asunto(s)
Trasplante de Riñón/estadística & datos numéricos , Trasplante de Hígado/estadística & datos numéricos , Trasplante de Pulmón/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Adolescente , Adulto , Anciano , Estudios de Cohortes , Bases de Datos Factuales , Muerte , Femenino , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Ontario , Estudios Retrospectivos , Factores de Tiempo , Donantes de Tejidos/estadística & datos numéricos , Resultado del Tratamiento , Adulto Joven
13.
Lancet Reg Health Eur ; 2: 100015, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33870245

RESUMEN

BACKGROUND: Military personnel in enclosed societies are at increased risk of respiratory infections. We investigated an outbreak of Coronavirus Disease 2019 in a London Army barracks early in the pandemic. METHODS: Army personnel, their families and civilians had nasal and throat swabs for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by reverse transcriptase -polymerase chain reaction (RT-PCR), virus isolation and whole genome sequencing, along with blood samples for SARS-CoV-2 antibodies. All tests were repeated 36 days later. FINDINGS: During the first visit, 304 (254 Army personnel, 10 family members, 36 civilians, 4 not stated) participated and 24/304 (8%) were SARS-CoV-2 RT-PCR positive. Infectious virus was isolated from 7/24 (29%). Of the 285 who provided a blood sample, 7% (19/285) were antibody positive and 63% (12/19) had neutralising antibodies. Twenty-two (22/34, 64%) individuals with laboratory-confirmed infection were asymptomatic. Nine SARS-CoV-2 RT-PCR positive participants were also antibody positive but those who had neutralising antibodies did not have infectious virus. At the second visit, no new infections were detected, and 13% (25/193) were seropositive, including 52% (13/25) with neutralising antibodies. Risk factors for SARS-CoV-2 antibody positivity included contact with a confirmed case (RR 25.2; 95% CI 14-45), being female (RR 2.5; 95% CI 1.0-6.0) and two-person shared bathroom (RR 2.6; 95% CI 1.1-6.4). INTERPRETATION: We identified high rates of asymptomatic SARS-CoV-2 infection. Public Health control measures can mitigate spread but virus re-introduction from asymptomatic individuals remains a risk. Most seropositive individuals had neutralising antibodies and infectious virus was not recovered from anyone with neutralising antibodies. FUNDING: PHE.

15.
Can J Surg ; 53(2): 93-102, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20334741

RESUMEN

BACKGROUND: The disparity between the number of patients waiting for an organ transplant and availability of donor organs increases each year in Canada. Donation after cardiac death (DCD), following withdrawal of life support in patients with hopeless prognoses, is a means of addressing the shortage with the potential to increase the number of transplantable organs. METHODS: We conducted a retrospective, single-centre chart review of organs donated after cardiac death to the Multi-Organ Transplant Program at the London Health Sciences Centre between July 2006 and December 2007. In total, 34 solid organs (24 kidneys and 10 livers) were procured from 12 DCD donors. RESULTS: The mean age of the donors was 38 (range 18-59) years. The causes of death were craniocerebral trauma (n = 7), cerebrovascular accident (n = 4) and cerebral hypoxia (n = 1). All 10 livers were transplanted at our centre, as were 14 of the 24 kidneys; 10 kidneys were transplanted at other centres. The mean renal cold ischemia time was 6 (range 3-9.5) hours. Twelve of the 14 kidney recipients (86%) experienced delayed graft function, but all kidneys regained function. After 1-year follow-up, kidney function was good, with a mean serum creatinine level of 145 (range 107-220) micromol/L and a mean estimated creatinine clearance of 64 (range 41-96) mL/min. The mean liver cold ischemia time was 5.8 (range 5.5-8) hours. There was 1 case of primary nonfunction requiring retransplantation. The remaining 9 livers functioned well. One patient developed a biliary anastomotic stricture that resolved after endoscopic stenting. All liver recipients were alive after a mean follow-up of 11 (range 3-20) months. Since the inception of this DCD program, the number of donors referred to our centre has increased by 14%. CONCLUSION: Our initial results compare favourably with those from the transplantation of organs procured from donors after brain death. Donation after cardiac death can be an important means of increasing the number of organs available for transplant, and its widespread implementation in Canada should be encouraged.


Asunto(s)
Muerte , Paro Cardíaco , Trasplante de Riñón , Trasplante de Hígado , Donantes de Tejidos , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación/estadística & datos numéricos , Cuidados para Prolongación de la Vida , Masculino , Persona de Mediana Edad , Ontario , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Tiempo , Obtención de Tejidos y Órganos , Resultado del Tratamiento , Privación de Tratamiento , Adulto Joven
16.
Liver Transpl ; 15(12): 1696-702, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19938124

RESUMEN

Acute liver failure continues to be associated with a high mortality rate, and emergency liver transplantation is often the only life-saving treatment. The short-term outcomes are decidedly worse in comparison with those for nonurgent cases, whereas the long-term results have not been reported as extensively. We report our center's experience with urgent liver transplantation, long-term survival, and major complications. From 1994 to 2007, 60 patients had emergency liver transplantation for acute liver failure. The waiting list mortality rate was 6%. The mean waiting time was 2.7 days. Post-transplantation, the perioperative mortality rate was 15%, and complications included neurological problems (13%), biliary problems (10%), and hepatic artery thrombosis (5%). The 5- and 10-year patient survival rates were 76% and 69%, respectively, and the graft survival rates were 65% and 59%. Recipients of blood group-incompatible grafts had an 83% retransplantation rate. Univariate analysis by Cox regression analysis found that cerebral edema and extended criteria donor grafts were associated with worse long-term survival. Severe cerebral edema on a computed tomography scan pre-transplant was associated with either early mortality or permanent neurological deficits. The keys to long-term success and continued progress in urgent liver transplantation are the use of good-quality whole grafts and a short waiting list time, both of which depend on access to a sufficient pool of organ donors. Severe preoperative cerebral edema should be a relative contraindication to transplantation.


Asunto(s)
Fallo Hepático Agudo/cirugía , Trasplante de Hígado , Sobrevivientes , Adolescente , Adulto , Anciano , Edema Encefálico/complicaciones , Contraindicaciones , Tratamiento de Urgencia , Femenino , Humanos , Estimación de Kaplan-Meier , Fallo Hepático Agudo/etiología , Fallo Hepático Agudo/mortalidad , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/etiología , Ontario/epidemiología , Selección de Paciente , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Sobrevivientes/estadística & datos numéricos , Factores de Tiempo , Donantes de Tejidos/provisión & distribución , Resultado del Tratamiento , Listas de Espera , Adulto Joven
17.
Transplantation ; 83(12): 1571-6, 2007 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-17589339

RESUMEN

BACKGROUND: Total immunosuppression withdrawal (TIW) without causing rejection has been reported in stable liver recipients. The role of ursodeoxycholic acid (UDCA) and patient characteristics that predict the success of this tolerance are unclear. There are two goals, to determine: 1) whether TIW is frequently associated with rejection; and 2) whether UDCA decreases the risk of liver disease (both rejection and recurrence) after TIW. METHODS: Twenty-six liver recipients who had been free of rejection while on immunosuppressive agents for a minimum of 2 years were randomized to receive either (15 mg/kg) of UDCA (n=14) or identical placebo (n=12) followed by sequential withdrawal of their immunosuppressive regimen over several months. Endpoints were defined as biochemical and histological evidence of rejection, graft dysfunction without rejection, recurrence of pretransplant disease, or 6 months without immunosuppression and no rejection or dysfunction on repeat liver biopsy. RESULTS: Rejection occurred in 6 of 14 (43%) of the UDCA group and 9 of 12 (75%) of those receiving placebo (P=0.09). Degree of rejection was mild, moderate, and severe in 73%, 20%, and 7% of patients respectively. All responded to rescue therapy and none developed chronic rejection. Nine of the remaining 11 patients (eight of the UDCA recipients and three of controls) who did not develop rejection developed graft dysfunction which responded to reintroduction of immunosuppressive agents in each case. Disease recurrence was most common in patients with underlying immune-mediated disorders of the liver. One year after withdrawal only two patients were free of immunosuppression, 80% were able to discontinue prednisone therapy (steroid free), and 50% were able to reduce their dose of cyclosporine. Age, underlying cause of liver disease, and regimen of immunosuppression were favorable predictors. CONCLUSIONS: The results of this study suggest that TIW: 1) is frequently associated with subsequent rejection, 2) increases the risk of underlying disease recurrence, and 3) is not facilitated by UDCA use and responds properly to the reintroduction of immunosuppressive therapy.


Asunto(s)
Colagogos y Coleréticos/uso terapéutico , Inmunosupresores/uso terapéutico , Trasplante de Hígado/inmunología , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Anciano , Ciclosporina/uso terapéutico , Esquema de Medicación , Femenino , Estudios de Seguimiento , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/epidemiología , Humanos , Inmunosupresores/administración & dosificación , Hepatopatías/cirugía , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Placebos , Prednisona/uso terapéutico , Seguridad
18.
Transplantation ; 81(2): 273-83, 2006 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-16436972

RESUMEN

BACKGROUND: The present study was undertaken to determine the role of preformed and induced anti-non-Gal antibodies in the rejection of hDAF pig-to-baboon kidney xenotransplants after anti-Gal antibody neutralization therapy. METHODS: Seven baboons received life-supporting kidney transplants from hDAF transgenic pigs. Anti-Gal antibodies were neutralized by GAS914 or TPC (a Gal PEG glycoconjugate polymer). Group 1 (n=5) underwent a conventional immunosuppressive therapy with FK506, rabbit anti-thymocyte serum/immunoglobulin, mycophenolate mofetil, and steroids. Group 2 (n=2) received an anti-humoral immunity regimen with LF15-0195, Rituxan and cobra venom factor in addition to ATG, FK506 and steroids. Levels of anti-non-Gal antibodies and their mediated complement-dependent cytotoxic activities (CDC) were detected by flow cytometry using Gal knockout (k/o) pig lymphocytes (LC) or endothelial cells (EC) as targets. RESULTS: Continuous infusion of GAS914/TPC significantly reduced anti-Gal antibodies. In Group 1, four of five baboons developed severe acute humoral xenograft rejection (AHXR) and the rejection was associated with either a high level of preformed anti-non-Gal IgG or a marked elevation in induced anti-non-Gal IgG and IgM. Sera collected at the time of AHXR had a high level of CDC to porcine LC/EC from Gal k/o animals. The intensive anti-humoral therapy in Group 2 completely inhibited both anti-Gal and non-Gal antibody production and prevented AHXR. However, this therapy was not well tolerated by the baboons. CONCLUSION: In a pig-to-baboon kidney transplant model, both preformed and induced anti-non-Gal antibodies are strongly associated with the pathogenesis of AHXR when anti-Gal antibodies are neutralized.


Asunto(s)
Anticuerpos Heterófilos/biosíntesis , Rechazo de Injerto/inmunología , Trasplante de Riñón/inmunología , Trisacáridos/inmunología , Enfermedad Aguda , Animales , Animales Modificados Genéticamente , Rechazo de Injerto/etiología , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/patología , Pruebas de Neutralización , Papio , Sus scrofa , Trasplante Heterólogo
19.
CMAJ ; 175(8): S1, 2006 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-17124739

RESUMEN

These recommendations are the result of a national, multidisciplinary, year-long process to discuss whether and how to proceed with organ donation after cardiocirculatory death (DCD) in Canada. A national forum was held in February 2005 to discuss and develop recommendations on the principles, procedures and practice related to DCD, including ethical and legal considerations. At the forum's conclusion, a strong majority of participants supported proceeding with DCD programs in Canada. The forum also recognized the need to formulate and emphasize core values to guide the development of programs and protocols based on the medical, ethical and legal framework established at this meeting. Although end-of-life care should routinely include the opportunity to donate organs and tissues, the duty of care toward dying patients and their families remains the dominant priority of health care teams. The complexity and profound implications of death are recognized and should be respected, along with differing personal, ethnocultural and religious perspectives on death and donation. Decisions around withdrawal of life-sustaining therapies, management of the dying process and the determination of death by cardiocirculatory criteria should be separate from and independent of donation and transplant processes. The recommendations in this report are intended to guide individual programs, regional health authorities and jurisdictions in the development of DCD protocols. Programs will develop based on local leadership and advance planning that includes education and engagement of stakeholders, mechanisms to assure safety and quality and public information. We recommend that programs begin with controlled DCD within the intensive care unit where (after a consensual decision to withdraw life-sustaining therapy) death is anticipated, but has not yet occurred, and unhurried consent discussions can be held. Uncontrolled donation (where death has occurred after unanticipated cardiac arrest) should only be considered after a controlled DCD program is well established. Although we recommend that programs commence with kidney donation, regional transplant expertise may guide the inclusion of other organs. The impact of DCD, including pre-and post-mortem interventions, on donor family experiences, organ availability, graft function and recipient survival should be carefully documented and studied.


Asunto(s)
Muerte , Cuidado Terminal , Donantes de Tejidos , Obtención de Tejidos y Órganos/ética , Obtención de Tejidos y Órganos/legislación & jurisprudencia , Canadá , Toma de Decisiones , Humanos , Preservación de Órganos , Desarrollo de Programa , Terminología como Asunto , Privación de Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA