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1.
JAMA ; 322(18): 1789-1798, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714985

RESUMO

Importance: In the United States, the number of deceased donor hearts available for transplant is limited. As a proxy for medical urgency, the US heart allocation system ranks heart transplant candidates largely according to the supportive therapy prescribed by transplant centers. Objective: To determine if there is a significant association between transplant center and survival benefit in the US heart allocation system. Design, Setting, and Participants: Observational study of 29 199 adult candidates for heart transplant listed on the national transplant registry from January 2006 through December 2015 with follow-up complete through August 2018. Exposures: Transplant center. Main Outcomes and Measures: The survival benefit associated with heart transplant as defined by the difference between survival after heart transplant and waiting list survival without transplant at 5 years. Each transplant center's mean survival benefit was estimated using a mixed-effects proportional hazards model with transplant as a time-dependent covariate, adjusted for year of transplant, donor quality, ischemic time, and candidate status. Results: Of 29 199 candidates (mean age, 52 years; 26% women) on the transplant waiting list at 113 centers, 19 815 (68%) underwent heart transplant. Among heart transplant recipients, 5389 (27%) died or underwent another transplant operation during the study period. Of the 9384 candidates who did not undergo heart transplant, 5669 (60%) died (2644 while on the waiting list and 3025 after being delisted). Estimated 5-year survival was 77% (interquartile range [IQR], 74% to 80%) among transplant recipients and 33% (IQR, 17% to 51%) among those who did not undergo heart transplant, which is a survival benefit of 44% (IQR, 27% to 59%). Survival benefit ranged from 30% to 55% across centers and 31 centers (27%) had significantly higher survival benefit than the mean and 30 centers (27%) had significantly lower survival benefit than the mean. Compared with low survival benefit centers, high survival benefit centers performed heart transplant for patients with lower estimated expected waiting list survival without transplant (29% at high survival benefit centers vs 39% at low survival benefit centers; survival difference, -10% [95% CI, -12% to -8.1%]), although the adjusted 5-year survival after transplant was not significantly different between high and low survival benefit centers (77.6% vs 77.1%, respectively; survival difference, 0.5% [95% CI, -1.3% to 2.3%]). Overall, for every 10% decrease in estimated transplant candidate waiting list survival at a given center, there was an increase of 6.2% (95% CI, 5.2% to 7.3%) in the 5-year survival benefit associated with heart transplant. Conclusions and Relevance: In this registry-based study of US heart transplant candidates, transplant center was associated with the survival benefit of transplant. Although the adjusted 5-year survival after transplant was not significantly different between high and low survival benefit centers, compared with centers with survival benefit significantly below the mean, centers with survival benefit significantly above the mean performed heart transplant for recipients who had significantly lower estimated expected 5-year waiting list survival without transplant.


Assuntos
Transplante de Coração/mortalidade , Avaliação de Resultados em Cuidados de Saúde , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Qualidade da Assistência à Saúde , Sistema de Registros , Alocação de Recursos , Análise de Sobrevida , Estados Unidos/epidemiologia , Listas de Espera
2.
Semin Respir Crit Care Med ; 34(3): 275-80, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23821502

RESUMO

The number of donors falls short of the number of patients on the wait list for lung transplantation making it necessary to ration the available donor organs. The ideal allocation system is guided by ethical principles and scientifically accurate at identifying patients who will gain the greatest degree of benefit from receiving the organ, in terms of both pre- and posttransplantation survival. The lung allocation score (LAS) was developed in 2005 to reduce mortality on the wait list, prioritize candidates based on urgency, minimize the role of geography, and maximize transplant benefit. The LAS has not made much of an impact on the geographic disparity of listing patients for lung transplantation, but it did achieve the goal of reducing wait-list mortality and prioritizing patients based on urgency. In prioritizing patients with the most urgent status, a new controversy has come into the forefront: whether or not the increased number of critically ill recipients maximizes transplant benefit. Despite the controversy, the LAS system is an improvement compared with the traditional first-come, first-served system, and it has even been adopted by Eurotransplant. In the future, as modifications are made to improve the LAS, the issue of critically ill patients and maximizing posttransplant benefit will be the focus.


Assuntos
Pneumopatias/cirurgia , Transplante de Pulmão/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Estado Terminal , Humanos , Pneumopatias/fisiopatologia , Transplante de Pulmão/ética , Análise de Sobrevida , Fatores de Tempo , Doadores de Tecidos/provisão & distribuição , Listas de Espera
3.
J Heart Lung Transplant ; 41(2): 217-225, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34802876

RESUMO

BACKGROUND: The United States (US) Lung Allocation Score (LAS) relies on the performance of 2 survival models that estimate waitlist and post-transplant survival. These models were developed using data from 2005 to 2008, and it is unknown if they remain accurate. METHODS: We performed an observational cohort study of US lung transplantation candidates and recipients greater than 12 years of age between February 19, 2015 and February 19, 2019. We evaluated the LAS waitlist and post-transplant models with the concordance probability estimate and by comparing predicted vs observed 1-year restricted mean survival times by risk decile. We then compared a nonparametric estimate of the observed LAS with the predicted LAS for each percentile of recipients. RESULTS: The waitlist model ranked candidates (N = 11,539) in the correct risk order 72% of the time (95% CI 71%-73%), and underestimated candidate one-year survival by 136 days for the highest risk decile (p < 0.001). The post-transplant model ranked recipients (N = 9,377) in the correct risk order 57% of the time (95% CI 55-58%), and underestimated recipient one-year survival by 70 days for the highest risk decile (p < 0.001). Overall, the LAS at transplant explained only 56% of the variation in observed outcomes, and was increasingly inaccurate at higher predicted values. CONCLUSIONS: The waitlist and the post-transplant models that constitute the LAS are inaccurate, limiting the ability of the system to rank candidates on the waitlist in the correct order. The LAS should therefore be updated and the underlying models should be modernized.


Assuntos
Transplante de Pulmão/mortalidade , Sistema de Registros , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Transplantados/estatística & dados numéricos , Listas de Espera/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
4.
Respir Res ; 12: 44, 2011 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21477368

RESUMO

BACKGROUND: While lung transplantation is an increasingly utilized therapy for advanced lung diseases, chronic rejection in the form of bronchiolitis obliterans syndrome (BOS) continues to result in significant allograft dysfunction and patient mortality. Despite correlation of clinical events with eventual development of BOS, the causative pathophysiology remains unknown. Airway epithelial cells within the region of inflammation and fibrosis associated with BOS may have a participatory role. METHODS: Transplant derived airway epithelial cells differentiated in air liquid interface culture were treated with IL-1ß and/or cyclosporine, after which secretion of cytokines and growth factor and gene expression for markers of epithelial to mesenchymal transition were analyzed. RESULTS: Secretion of IL-6, IL-8, and TNF-α, but not TGF-ß1, was increased by IL-1ß stimulation. In contrast to previous studies using epithelial cells grown in submersion culture, treatment of differentiated cells in ALI culture with cyclosporine did not elicit cytokine or growth factor secretion, and did not alter IL-6, IL-8, or TNF-α production in response to IL-1ß treatment. Neither IL-1ß nor cyclosporine elicited expression of markers of the epithelial to mesenchymal transition E-cadherin, EDN-fibronectin, and α-smooth muscle actin. CONCLUSION: Transplant derived differentiated airway epithelial cell IL-6, IL-8, and TNF-α secretion is not regulated by cyclosporine in vitro; these cells thus may participate in local inflammatory responses in the setting of immunosuppression. Further, treatment with IL-1ß did not elicit gene expression of markers of epithelial to mesenchymal transition. These data present a model of differentiated airway epithelial cells that may be useful in understanding epithelial participation in airway inflammation and allograft rejection in lung transplantation.


Assuntos
Bronquiolite Obliterante/etiologia , Ciclosporina/farmacologia , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Imunossupressores/farmacologia , Mediadores da Inflamação/metabolismo , Transplante de Pulmão/efeitos adversos , Mucosa Respiratória/efeitos dos fármacos , Adulto , Bronquiolite Obliterante/genética , Bronquiolite Obliterante/imunologia , Bronquiolite Obliterante/patologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/imunologia , Células Epiteliais/patologia , Células Epiteliais/transplante , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pessoa de Meia-Idade , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Mucosa Respiratória/transplante , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
5.
Semin Respir Crit Care Med ; 31(2): 108-14, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354924

RESUMO

The lung allocation score (LAS) was developed in an effort to facilitate lung transplantation to more urgent and ill patients, to decrease wait time, and to change the allocation process to a more merit-based system. Four years after the implementation of the LAS, we now evaluate the impact and outcomes of this system. We have found that registrations on the wait list as well as wait time have decreased. Mortality on the wait list has decreased. There has been significant change in the distribution of diagnoses receiving transplantation with no significant difference in survival in most areas. Patients with higher LAS scores have increased short-term mortality. The LAS has affected the allocation process as well as significant outcomes in the transplant patient population.


Assuntos
Pneumopatias/cirurgia , Transplante de Pulmão/métodos , Seleção de Pacientes , Alocação de Recursos para a Atenção à Saúde , Humanos , Índice de Gravidade de Doença , Perfil de Impacto da Doença , Análise de Sobrevida , Fatores de Tempo , Obtenção de Tecidos e Órgãos , Estados Unidos , Listas de Espera
6.
Int Surg ; 95(4): 299-304, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21309410

RESUMO

Causes of early readmissions following lung transplantation are not well understood, and the impact is poorly reported. We reviewed 221 consecutive lung transplantations and identified patients readmitted within 90 days. A case control analysis was performed to determine the characteristics that predict readmission and the impact of readmission on survival. Ninety (44%) of the 205 operative survivors required a total of 125 readmissions during the 90 days after transplantation. Twenty-eight patients (13.7%) required multiple readmissions. Causes for readmissions were pulmonary complication (59%), gastrointestinal (18%), cardiac (5%), metabolic (2.5%), neurological (2.5%), hematological (2%), and miscellaneous (11%). The sex, native disease, or type of transplant did not predict readmission. Requirement of cardiopulmonary bypass for transplantation showed a trend toward significance (P = 0.08). The 90-day conditional survival at 1, 3, and 5 years for those patients readmitted within 90 days were 76%, 59%, and 52%, respectively, compared to 93%, 80%, and 76% for patients not readmitted (P = 0.01). Requirement for readmission within 90 days following transplantation is associated with increased mortality. Sex, native disease, and type of transplant are not predictors of readmission or survival.


Assuntos
Transplante de Pulmão , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Valor Preditivo dos Testes , Taxa de Sobrevida
8.
J Am Coll Cardiol ; 71(16): 1715-1725, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29666020

RESUMO

BACKGROUND: The current U.S. priority ranking for heart candidates is based on treatment intensity, not objective markers of severity of illness. This system may encourage centers to overtreat candidates. OBJECTIVES: This study sought to describe national variation in the intensity of treatment of adult heart transplantation candidates and identify center-level predictors of potential overtreatment. METHODS: The registrations of all U.S. adult heart transplantation candidates from 2010 to 2015 were collected from the SRTR (Scientific Registry of Transplant Recipients). "Potential overtreatment" was defined as treatment of a candidate who did not meet American Heart Association cardiogenic shock criteria with either high-dose inotropes or an intra-aortic balloon pump. Multilevel logistic regression and propensity score models were used to adjust for candidate variability at each center. Center-level variables associated with potential overtreatment were identified. RESULTS: From 2010 to 2015, 108 centers listed 12,762 adult candidates who were not in cardiogenic shock for heart transplantation. Of these, 1,471 (11.6%) were potentially overtreated with high-dose inotropes or intra-aortic balloon pumps. In the bottom quartile of centers, only 2.1% of candidates were potentially overtreated compared with 27.6% at top quartile centers, an interquartile difference of 25.5% (95% confidence interval: 21% to 30%). Adjusting for candidate differences did not significantly alter the interquartile difference. Local competition with 2 or more centers increased the odds of potential overtreatment by 50% (adjusted odds ratio: 1.50; 95% confidence interval: 1.07 to 2.11). CONCLUSIONS: There is wide variation in the treatment practices of adult heart transplantation centers. Competition for transplantable donor hearts is associated with the potential overtreatment of hemodynamically stable candidates. Overtreatment may compromise the fair and efficient allocation of scarce deceased donor hearts.


Assuntos
Transplante de Coração , Uso Excessivo dos Serviços de Saúde , Sistema de Registros , Obtenção de Tecidos e Órgãos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estados Unidos
9.
Chest ; 132(5): 1646-51, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17998365

RESUMO

Since the first successful single-lung transplant in 1983 and double-lung transplant in 1986, thousands of patients have benefited from the procedures. Until 1995, allocation of donor lungs was based purely on time on the waiting list. In 1995, a 90-day credit was given to patients with idiopathic pulmonary fibrosis, while still maintaining allocation based on waiting list time. In 2005, the lung allocation score (LAS) was implemented, dramatically changing the way lungs are allocated. This article will explore the reasons for the creation of the LAS, the design of the score, early experience with transplant results under the new system, and further changes that may be made to the system of lung allocation. As surgical techniques and medical management evolve, so to will the management of potential donors and the allocation of their organs, with the aim of benefiting patients needing lung transplantation in the United States.


Assuntos
Transplante de Pulmão/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Humanos , Transplante de Pulmão/tendências , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Obtenção de Tecidos e Órgãos/tendências , Estados Unidos/epidemiologia , Listas de Espera
10.
Chest ; 131(2): 533-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17296658

RESUMO

BACKGROUND: Acute rejection remains a major source of morbidity in lung transplantation. Although interleukin (IL)-2 has been the principal T-cell growth factor implicated in acute rejection, IL-2 blockade does not prevent acute rejection completely. Recently, IL-15, a stromal cell-derived cytokine, has been found to share a similar biological function with IL-2. We hypothesized that IL-15 levels may be elevated in acute lung rejection in the presence of IL-2 blockade. METHODS: Acute allograft rejection developed in 21 of 42 lung transplant recipients. BAL fluid (BALF) was analyzed for IL-2 and IL-15 protein expression by standard enzyme-linked immunosorbent assay. RESULTS: The average (+/- SD) BALF IL-15 level was higher in lung transplant recipients with acute rejection compared to those without rejection (25 +/- 25 pg/mL vs 4.5 +/- 1.5 pg/mL, respectively; p < 0.0001). In addition, there appeared to be a bimodal distribution of BALF IL-15 levels in lung transplant recipients with acute rejection. BALF IL-2 levels were not associated with acute rejection. BALF IL-15 levels were not associated with bacterial, fungal, or cytomegalovirus infection. CONCLUSION: These data show that BALF IL-15 levels are elevated in acute lung allograft rejection in the presence of IL-2 receptor blockade and may be an important mediator for acute rejection in lung transplantation.


Assuntos
Líquido da Lavagem Broncoalveolar/química , Rejeição de Enxerto/metabolismo , Interleucina-15/análise , Interleucina-2/análise , Transplante de Pulmão , Adulto , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Broncoscopia , Daclizumabe , Feminino , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/patologia , Humanos , Imunoglobulina G/uso terapêutico , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-2/antagonistas & inibidores
11.
Int Surg ; 92(2): 93-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17518251

RESUMO

Transplant programs are under pressure to resolve multiple challenges related to quality, cost, and access in a resource-driven customer-focused health care environment. We reviewed outcomes of patients undergoing isolated lung transplantation using a single postoperative clinical pathway, developed between the specialties of Thoracic Surgery, Pulmonary and Critical Care Medicine, and Nursing. The data were retrospectively reviewed for mortality, length to extubation (LE), hospital length of stay (LOS), and readmissions of 183 consecutive patients. One hundred ten women and 73 men with a mean age of 48 +/- 12 years underwent 90 bilateral, 88 single, and 6 repeat lung transplantations. Median LE was 17 hours, and the LOS was 7 days. The operative mortality was 6.5%. One- and 3-year survivals were 82% and 73%, respectively. We conclude that a single multidisciplinary clinical pathway can facilitate early discharge from the hospital. Early hospital discharge after lung transplantation does not compromise early or late outcome.


Assuntos
Procedimentos Clínicos , Tempo de Internação , Transplante de Pulmão , Avaliação de Resultados em Cuidados de Saúde , Adulto , Estudos de Coortes , Feminino , Seguimentos , Sobrevivência de Enxerto , Hospitalização/estatística & dados numéricos , Humanos , Intubação Intratraqueal/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
12.
Circ Heart Fail ; 10(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29246896

RESUMO

BACKGROUND: The number of adult heart transplant candidates waiting at the most urgent status 1A has increased over time despite the expansion of geographic sharing of hearts in 2006. We aimed to determine whether candidates listed with inotropes contribute to the excess status 1A candidates. METHODS AND RESULTS: The initial registrations of all adult heart-only candidates listed from 2000 to 2015 were analyzed using the Scientific Registry of Transplant Recipients data set. Trends in listing status, justifications, and candidate factors were measured. Adjusted trends in listing status pre- and post-geographic sharing were estimated using multilevel logistic regression. Competing risks models provided trends in transplant-free waitlist survival. There were 46 853 adult heart-alone listings during 2000 to 2015. Pre-sharing, status 1A listing was unchanged over time (adjusted odds ratio, 0.98; 95% confidence interval, 0.78-1.23). Post-sharing, the adjusted odds of status 1A listing increased 117% over 9 years (adjusted odds ratio 2.17, 95% confidence interval, 1.82-2.58). The number of candidates listed as status 1A with inotropes increased by 193 a year, whereas the dobutamine, dopamine, and milrinone doses used decreased 49%, 55%, and 29% (P<0.001). The risk of waitlist death or deterioration of status 1A inotrope candidates relative to status 2 candidates decreased 62% for 2006 to 2010 and 70% for 2011 to 2015 compared with that for 2003 to 2006. CONCLUSIONS: After the wider geographic sharing of hearts in 2006, transplant programs used multiple inotropes to list candidates at status 1A more frequently with progressively lower doses. Concurrently, the status 1A inotrope candidate waitlist outcomes improved substantially. These trends suggest that overtreatment with multiple inotropes contributes to the current critical excess of status 1A candidates.


Assuntos
Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Transplante de Coração/mortalidade , Sistema de Registros , Obtenção de Tecidos e Órgãos/tendências , Transplantados , Listas de Espera/mortalidade , Adulto , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo , Estados Unidos/epidemiologia
13.
Chest ; 130(3): 847-54, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16963685

RESUMO

STUDY OBJECTIVES: Chronic allograft rejection is the leading cause of morbidity and mortality for long-term survivors of lung transplantation. Previous studies have implicated only isolated genes in the development of chronic rejection and have not examined multiple pathways in an individual concurrently. Using microarray technology, we identified and compared gene expression profiling in lung transplant recipients with and without chronic rejection, and follow sequential expression of genes differentially expressed between the two groups. DESIGN: Prospective, cohort study. SETTING: Single lung transplant center. PATIENTS OR PARTICIPANTS: Eleven transplant recipients with chronic rejection were matched with 9 control transplant recipients. INTERVENTIONS: All recipients underwent surveillance bronchoscopies at predetermined times to rule out infection and/or acute rejection. Gene expression profiling was obtained from hybridizing BAL fluid cell RNA to a 96-gene microarray. MEASUREMENTS AND RESULTS: Fifteen genes were found to be significantly differentially expressed between the two patient groups, and they are involved in inflammatory, fibrotic, and apoptotic pathways. Temporal expression of the significant genes demonstrated a change in their levels at the onset of chronic rejection, with normalization to prerejection levels as rejection continued. CONCLUSIONS: We conclude that microarray technology is valuable in studying the mechanism of chronic lung rejection, and the expression of genes in multiple pathways is elevated in patients with chronic lung rejection.


Assuntos
Sequência de Bases/genética , Perfilação da Expressão Gênica , Rejeição de Enxerto/genética , Transplante de Pulmão/patologia , Transplante/patologia , Adulto , Apoptose/genética , Apoptose/fisiologia , Bronquiolite Obliterante/etiologia , Bronquiolite Obliterante/patologia , Bronquiolite Obliterante/fisiopatologia , Estudos de Coortes , Feminino , Regulação da Expressão Gênica/fisiologia , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Humanos , Inflamação/genética , Inflamação/patologia , Inflamação/fisiopatologia , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Família Multigênica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Estudos Prospectivos , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia , Fibrose Pulmonar/fisiopatologia , RNA/genética
14.
Virol J ; 3: 4, 2006 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-16409621

RESUMO

BACKGROUND: Although the sequence of the human cytomegalovirus (HCMV) genome is generally conserved among unrelated clinical strains, some open reading frames (ORFs) are highly variable. UL146 and UL147, which encode CXC chemokine homologues are among these variable ORFs. RESULTS: The region of the HCMV genome from UL146 through UL147A was analyzed in clinical strains for sequence variability, genotypic stability, and transcriptional expression. The UL146 sequences in clinical strains from two geographically distant sites were assigned to 12 sequence groups that differ by over 60% at the amino acid level. The same groups were generated by sequences from the UL146-UL147 intergenic region and the UL147 ORF. In contrast to the high level of sequence variability among unrelated clinical strains, the sequences of UL146 through UL147A from isolates of the same strain were highly stable after repeated passage both in vitro and in vivo. Riboprobes homologous to these ORFs detected multiple overlapping transcripts differing in temporal expression. UL146 sequences are present only on the largest transcript, which also contains all of the downstream ORFs including UL148 and UL132. The sizes and hybridization patterns of the transcripts are consistent with a common 3'-terminus downstream of the UL132 ORF. Early-late expression of the transcripts associated with UL146 and UL147 is compatible with the potential role of CXC chemokines in pathogenesis associated with viral replication. CONCLUSION: Clinical isolates from two different geographic sites cluster in the same groups based on the hypervariability of the UL146, UL147, or the intergenic sequences, which provides strong evidence for linkage and no evidence for interstrain recombination within this region. The sequence of individual strains was absolutely stable in vitro and in vivo, which indicates that sequence drift is not a mechanism for the observed sequence hypervariability. There is also no evidence of transcriptional splicing, although multiple overlapping transcripts extending into the adjacent UL148 and UL132 open reading frames were detected using gene-specific probes.


Assuntos
Quimiocinas CXC/genética , Citomegalovirus/genética , Genoma Viral , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Quimiocinas CXC/química , Citomegalovirus/classificação , Perfilação da Expressão Gênica , Instabilidade Genômica , Genótipo , Glicosilação , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Virais/química
15.
Arch Pathol Lab Med ; 140(3): 241-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26927718

RESUMO

CONTEXT: Lung transplantation has become a viable option for definitive treatment of several end-stage lung diseases for which there are no other options available. However, long-term survival continues to be limited by chronic lung allograft dysfunction, which primarily affects the airways. OBJECTIVE: To highlight the complications occurring mainly in the airways of the lung transplant recipient from the early to late posttransplant periods. DATA SOURCES: Review literature focusing on the airways in patients with lung transplants and clinical experience of the authors. CONCLUSIONS: Postsurgical complications and infections of the airways have decreased because of better techniques and management. Acute cellular rejection of the airways can be distinguished from infection pathologically and on cultures. Separating small from large airways need not be an issue because both are risk factors for bronchiolitis obliterans. Grading of airway rejection needs to be standardized. Chronic lung allograft dysfunction consists of both bronchiolitis obliterans and restrictive allograft syndrome, neither of which can be treated very effectively at present.


Assuntos
Rejeição de Enxerto/diagnóstico , Transplante de Pulmão/efeitos adversos , Pulmão/patologia , Complicações Pós-Operatórias/diagnóstico , Mucosa Respiratória/patologia , Bronquiolite Obliterante/diagnóstico , Bronquiolite Obliterante/imunologia , Bronquiolite Obliterante/patologia , Bronquiolite Obliterante/fisiopatologia , Diagnóstico Diferencial , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Humanos , Pulmão/imunologia , Pulmão/fisiopatologia , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/fisiopatologia , Disfunção Primária do Enxerto/diagnóstico , Disfunção Primária do Enxerto/imunologia , Disfunção Primária do Enxerto/patologia , Disfunção Primária do Enxerto/fisiopatologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/fisiopatologia , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/imunologia , Infecção da Ferida Cirúrgica/patologia , Infecção da Ferida Cirúrgica/fisiopatologia , Terminologia como Assunto , Transplante Homólogo/efeitos adversos
16.
Transplantation ; 77(9 Suppl): S68-74, 2004 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15201689

RESUMO

Much progress has been made in heart and lung transplantation over recent decades. The immune mechanisms that result in allograft rejection are now better understood, and the development of immunosuppressant therapies has decreased recipient mortality among transplant recipients. During the 1980s, immunosuppressant therapy primarily involved the use of corticosteroids and cyclosporine. However, while survival rates increased among transplant recipients, many patients experienced primary graft failures, acute and chronic rejection, as well as death. Until the introduction of tacrolimus in the early 1990s, all patients received the same immunosuppressant regimen, regardless of its effectiveness. Tacrolimus therapy has contributed much to the success rates of both heart and lung transplantation, and by 2001, it had become the preeminent immunosuppressant agent used in lung transplantation.


Assuntos
Transplante de Coração , Transplante de Pulmão , Ácido Micofenólico/análogos & derivados , Doença Aguda , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Humanos , Imunossupressores/uso terapêutico , Transplante de Pulmão/efeitos adversos , Ácido Micofenólico/uso terapêutico , Sirolimo/uso terapêutico , Tacrolimo/uso terapêutico
17.
Transplantation ; 75(4): 482-7, 2003 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-12605114

RESUMO

BACKGROUND: Brain death results in adverse pathophysiologic effects in many cadaveric donors, resulting in cardiovascular instability and poor organ perfusion. Hormonal resuscitation (HR) has been reported to stabilize and improve cardiac function in brain-dead donors. The goal of this study was to examine the effect of HR on the brain-dead donor on the number of organs transplanted per donor. METHODS: A retrospective analysis of all brain-dead donors recovered in the United States from January 1, 2000, to September 30, 2001, was conducted. HR consisted of a methylprednisolone bolus and infusions of vasopressin and either triiodothyronine or L-thyroxine. Univariate analyses and multivariate logistic regression analyses were used to detect differences between the HR group and those donors who did not receive HR. RESULTS: Of 10,292 consecutive brain-dead donors analyzed, 701 received three-drug HR. Univariate analysis showed the mean number of organs from HR donors (3.8) was 22.5% greater than that from nonhormonal resuscitation donors (3.1) (P <0.001). Multivariate analyses showed that HR was associated with the following statistically significant increased probabilities of an organ being transplanted from a donor: kidney 7.3%, heart 4.7%, liver 4.9%, lung 2.8%, and pancreas 6.0%. Extrapolation of these probabilities to the 5,921 brain-dead donors recovered in 2001 was calculated to yield a total increase of 2,053 organs. CONCLUSION: HR stabilizes certain brain-dead donors and is associated with significant increases in organs transplanted per donor.


Assuntos
Morte Encefálica , Esteroides/uso terapêutico , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adulto , Criança , Pré-Escolar , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Fármacos Renais/uso terapêutico , Ressuscitação , Estudos Retrospectivos , Tiroxina/uso terapêutico , Tri-Iodotironina/uso terapêutico , Vasopressinas/uso terapêutico
18.
Transplantation ; 75(8): 1336-41, 2003 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-12717226

RESUMO

BACKGROUND: Brain death results in cardiovascular instability and poor organ perfusion in many brain-dead donors. Hormonal resuscitation stabilizes certain brain-dead donors and is associated with significant increases in the numbers of organs transplanted per donor. The goal of this study was to examine the quality of hearts recovered from donors treated with hormonal resuscitation. METHODS: A retrospective analysis of 4,543 recipients of hearts recovered from brain-dead donors, reported to the United Network for Organ Sharing/Organ Procurement and Transplantation Network database between November 1, 1999, and December 31, 2001, was conducted. Hormonal resuscitation consisted of a methylprednisolone bolus and infusions of vasopressin and either triiodothyronine or l-thyroxine. Univariate and multivariate analyses were used to evaluate the quality of hearts from donors who received three-drug hormonal resuscitation (3HR) treatment versus donors who did not receive all three drugs (non-3HR). Death within 30 days and early graft dysfunction were used as endpoints. RESULTS: Hearts from 3HR donors demonstrated a 1-month survival rate of 96.2%, compared with a 92.1% survival rate for non-3HR donor hearts (P<0.01). Early graft dysfunction occurred in 5.6% of 3HR donor hearts and 11.6% of non-3HR donor hearts (P<0.01). Multivariate results demonstrated a 46% reduced odds of death within 30 days and a 48% reduced odds of early graft dysfunction. Steroids alone and steroids plus triiodothyronine/l-thyroxine also significantly reduced prolonged graft dysfunction. CONCLUSIONS: This study suggests that 3HR treatment of brain-dead donors results in increased numbers of transplanted hearts, with improved short-term graft function.


Assuntos
Morte Encefálica , Transplante de Coração , Coração/fisiopatologia , Hormônios/uso terapêutico , Ressuscitação/métodos , Doadores de Tecidos , Adulto , Feminino , Glucocorticoides , Humanos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Tiroxina/uso terapêutico , Fatores de Tempo , Sobrevivência de Tecidos , Tri-Iodotironina/uso terapêutico , Vasopressinas/uso terapêutico
19.
Chest ; 125(6): 2188-95, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15189941

RESUMO

STUDY OBJECTIVES: We previously reported that patients with emphysema show an increase in diaphragmatic neuromechanical coupling at 3 months after lung volume reduction surgery. Diaphragmatic neuromechanical coupling was quantified as the quotient of tidal volume (normalized to total lung capacity) to tidal change in transdiaphragmatic pressure (normalized to maximal transdiaphragmatic pressure). As such, neuromechanical coupling estimates the fraction of diaphragmatic capacity used to generate tidal breathing. The present investigation was conducted to determine whether benefit is maintained at 2 years. SUBJECTS: Fifteen patients with severe COPD, 8 of whom completed the 2-year study. METHODS: Lung volumes, exercise capacity (6-min walking distance), diaphragmatic function (maximal transdiaphragmatic pressure and twitch transdiaphragmatic pressure elicited by phrenic nerve stimulation), and diaphragmatic neuromechanical coupling were recorded before surgery, and at 3 months and 2 years after surgery. RESULTS: Two years after surgery, lung volumes deteriorated to preoperative values, but patients showed persistent improvements in 6-min walking distance (p < 0.05). Three months after surgery, maximal transdiaphragmatic pressure (p < 0.05), twitch transdiaphragmatic pressure (p < 0.01), and diaphragmatic neuromechanical coupling (p < 0.01) had increased over preoperative values. The improvements in neuromechanical coupling resulted from improvements in diaphragmatic strength and, to a lesser extent, from a decrease in transdiaphragmatic pressure required to maintain tidal breathing. The change in respiratory muscle function at 2 years varied among patients: diaphragmatic contractility was > 10% of preoperative value in half of the patients who concluded our study, and neuromechanical coupling was > 10% of preoperative value in three fourths of the patients who concluded our study. Patients who maintained their gains in neuromechanical coupling also maintained their gains in 6-min walking distance. CONCLUSION: Patients undergoing lung volume reduction surgery can maintain early gains in neuromechanical coupling and exercise capacity 2 years later.


Assuntos
Diafragma/fisiopatologia , Fadiga Muscular/fisiologia , Pneumonectomia/métodos , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/cirurgia , Músculos Respiratórios/fisiologia , Idoso , Resistência das Vias Respiratórias , Análise de Variância , Estudos de Coortes , Diafragma/inervação , Feminino , Seguimentos , Capacidade Residual Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Sistema Nervoso/fisiopatologia , Pneumonectomia/efeitos adversos , Probabilidade , Troca Gasosa Pulmonar , Testes de Função Respiratória , Mecânica Respiratória/fisiologia , Índice de Gravidade de Doença , Fatores de Tempo , Capacidade Pulmonar Total
20.
J Heart Lung Transplant ; 21(12): 1274-82, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12490272

RESUMO

BACKGROUND: Since ganciclovir-resistant cytomegalovirus (CMV) disease was initially described in a patient with acquired immunodeficiency syndrome (AIDS) in 1986, the incidence of ganciclovir-resistant CMV disease appears to be increasing in immunocompromised patients. More recently, there have been sporadic reports of ganciclovir-resistant CMV disease in solid organ transplantation. METHODS: We retrospectively assessed the incidence of ganciclovir-resistant CMV disease in all lung transplant recipients transplanted between 6/93 and 6/01 at Loyola University Medical Center. All patients underwent routine CMV blood culture, shell vial assay as well as phenotypic and genotypic anti-viral susceptibility testing according to a pre-determined schedule. The number of CMV episodes, intravenous ganciclovir use, acute and chronic rejection and survival data were documented for all patients. RESULTS: Twelve of 212 (6%) transplant recipients developed ganciclovir-resistant CMV disease. Ganciclovir resistance was associated with a higher number of CMV episodes (3.4 +/- 2.3 episodes/patient vs 1.7 +/- 0.7 episodes/patient [p < 0.05]) and an increased exposure to cumulative intravenous ganciclovir in the primary CMV-mismatched (D(+)R(-)) population (22 +/- 10 vs 13 +/- 7 days [p < 0.05]) compared with patients who did not develop ganciclovir resistance. In addition, the use of daclizumab therapy was associated with a 7-fold greater likelihood of developing ganciclovir resistance (p < 0.0001). The presence of ganciclovir-resistant CMV disease in our population was associated with a decreased survival that could be attributed to CMV disease itself (p < 0.05). CONCLUSIONS: By screening all lung transplant recipients with CMV disease for ganciclovir resistance, we were able to detect a higher incidence of ganciclovir-resistant CMV disease (6%) than previously seen in solid organ transplantation. High-risk patients (D(+)R(-) CMV serostatus) who receive anti-lymphocytic therapy should be monitored aggressively and treated to prevent the development of ganciclovir resistance and avert a negative outcome.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/efeitos dos fármacos , Ganciclovir/uso terapêutico , Transplante de Pulmão/efeitos adversos , Infecções Oportunistas/diagnóstico , Complicações Pós-Operatórias/virologia , Adulto , Estudos de Casos e Controles , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/tratamento farmacológico , DNA Viral/análise , Resistência Microbiana a Medicamentos , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Transplante de Pulmão/imunologia , Transplante de Pulmão/mortalidade , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Oportunistas/epidemiologia , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias/epidemiologia , Probabilidade , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Estatísticas não Paramétricas , Taxa de Sobrevida , Imunologia de Transplantes/fisiologia
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