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1.
J Glob Health ; 12: 05035, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35932238

RESUMO

Background: People with Down syndrome (DS) are one of the highest risk groups for mortality associated with COVID-19, but outcomes may differ across countries due to different co-morbidity profiles, exposures, and societal practices, which could have implications for disease management. This study is designed to identify differences in clinical presentation, severity, and treatment of COVID-19 between India and several high-income countries (HICs). Methods: We used data from an international survey to examine the differences in disease manifestation and management for COVID-19 patients with DS from India vs HIC. De-identified survey data collected from April 2020 to August 2021 were analysed. Results: COVID-19 patients with DS from India were on average nine years younger than those from HICs. Comorbidities associated with a higher risk for severe COVID-19 were more frequent among the patients from India than from HICs. Hospitalizations were more frequent among patients from India as were COVID-19-related medical complications. Treatment strategies differed between India and HICs, with more frequent use of antibiotics in India. The average severity score of 3.31 was recorded for Indian DS in contrast to 2.3 for European and 2.04 for US cases. Conclusions: Presentation and outcomes of COVID-19 among individuals with DS were more severe for patients from India than for those from HIC. Global efforts should especially target vaccination campaigns and other risk-reducing interventions for individuals with DS from low-income countries.


Assuntos
COVID-19 , Síndrome de Down , COVID-19/terapia , Países Desenvolvidos , Síndrome de Down/epidemiologia , Síndrome de Down/terapia , Humanos , Renda , Índia/epidemiologia
2.
Science ; 220(4596): 465-71, 1983 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17816205

RESUMO

With the ever-increasing complexity of integrated circuits, manual design methods have become intolerably slow and error-prone. The use of computers to automate some or all of the design process is necessary to minimize both design time and error incidence. In this article are discussed the design and fabrication of integrated circuits, selected techniques of design automation, and the problems associated with such automation.

3.
Transplantation ; 68(2): 315-7, 1999 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10440411

RESUMO

Granular cell tumor is a rare cause of hepatic dysfunction. We report here on a patient who underwent liver transplantation for this ailment. In our literature review, the common bile duct was most commonly involved (56%). A wide variety of therapies were advanced for this type of lesion, spanning three decades of care. Twenty-eight patients (49%) had no follow-up reported, and another 2 (3%) were found at autopsy. Sixteen patients (28%) were followed more than 1 year, with 72% followed less than 1 year if at all. We present the first case of a granular cell tumor being treated with liver transplantation. Although adequate early excisional surgery should obviate the need for transplantation in these cases, widely disparate therapy and poor follow-up may mask generally inadequate therapy for this lesion. The authors recommend thorough excision and long-term follow-up for patients with this entity to avoid secondary biliary cirrhosis and to eliminate the preventable need for transplantation.


Assuntos
Neoplasias do Sistema Biliar/complicações , Tumor de Células Granulares/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/cirurgia , Transplante de Fígado , Adulto , Feminino , Seguimentos , Humanos
4.
Transplantation ; 61(4): 542-6, 1996 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-8610378

RESUMO

The degree to which immunosuppression and/or rejection influences recurrent hepatitis C (HCV) after liver transplantation (LT) for end-stage HCV cirrhosis remains poorly defined. We quantified serum HCV-RNA in 84 serum samples from 28 anti-HCV-positive patients taken 223 days prior to and up to 1719 days after liver transplantation to determine if cumulative immunosuppression, rejection, or histologic recurrence correlated with HCV-RNA levels. Histologic, serum chemistry, cumulative steroid, and OKT3 and alpha-interferon (INF) dose data were collected at the time of HCV-RNA sampling. Eighteen of 24 evaluable patients (75%) had HCV-RNA detected in their sera after transplant. Eight patients had 14 rejection episodes, 9 patients received OKT3, and 5 were given INF for histologically moderate hepatitis. Five patients died - two of recurrent hepatitis C - and no retransplants were performed for recurrent hepatitis. Of the 23 survivors, 7 have histologic hepatitis - 2 with persistent ascites, and 2 with mild fibrosis. We could show no correlation between HCV-RNA levels and any of the variables examined although a trend toward increasing HCV-RNA levels with increasing numbers of rejection episodes was observed. In addition, histologic recurrence occurred more frequently for patients treated with OKT3. We conclude that the quantity of circulating viral genome is not influenced by immunosuppressive load and does not correlate with laboratory or histologic signs of recurrence. The roles that rejection, and possibly OKT3, play in the recurrence of HCV after liver transplant need further study.


Assuntos
Hepacivirus/genética , Hepatite C/sangue , Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos , RNA Viral/sangue , Feminino , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Hepacivirus/imunologia , Hepatite C/imunologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Imunossupressores/uso terapêutico , Cirrose Hepática/cirurgia , Cirrose Hepática/virologia , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Muromonab-CD3/efeitos adversos , Muromonab-CD3/uso terapêutico , Estudos Retrospectivos
5.
Transplantation ; 67(11): 1492-4, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10385094

RESUMO

Transjugular intrahepatic portosystemic shunt has become an accepted intervention to treat sequelae of end-stage liver disease such as refractory ascites and esophageal varices for patients awaiting liver transplantation. Technical difficulties in such patients at the time of transplantation are usually limited to malpositioning of the stent requiring modification of the usual vascular anastomoses. Migration of the stent intraoperatively has not been a reported complication in the literature. We report a case in which a patient with a previously placed transjugular intrahepatic portosystemic shunt underwent successful liver transplantation complicated by intraoperative migration of the stent into the left pulmonary artery. The stent was removed from the pulmonary artery postoperatively using interventional radiology techniques.


Assuntos
Migração de Corpo Estranho/complicações , Transplante de Fígado/efeitos adversos , Derivação Portossistêmica Transjugular Intra-Hepática , Artéria Pulmonar/patologia , Migração de Corpo Estranho/diagnóstico por imagem , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Radiografia
6.
Transplantation ; 53(2): 376-82, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1310823

RESUMO

Although early survival following transplantation for primary hepatic cancer is excellent, previously reported high recurrence rates have generally discouraged liver replacement for this indication. Since the inception of the Boston Center for Liver Transplantation (BCLT) in 1983, 33 of 383 (8.6%) liver allograft recipients have undergone orthotopic transplantation as definitive treatment for otherwise unresectable cancer. Diagnoses included hepatocellular carcinoma (HCCA) in 24 patients (73%), and cholangiocarcinoma (CHCA) in 9 patients (27%). Actuarial survival rates for patients with hepatocellular carcinoma were 71%, 56%, and 42% at 1, 2, and 3 years, respectively. The actuarial survival rates for patients with cholangiocarcinoma were 89% at 6 months, and 56% at 1, 2, and 3 years. Of the nine patients with cholangiocarcinoma, 56% (5/9) developed recurrent disease. Although this recurrence rate is disheartening, because of the lack of other morbidity, long-term survival in these patients is comparable to patients with HCCA. In contrast, recurrent hepatocellular carcinoma developed in 25% of recipients (5/20) who survived longer than 3 months posttransplantation. Other causes of death in patients with hepatocellular carcinoma included perioperative complications, 16.6% (4/24); sepsis, 8.3% (2/24); coronary artery disease, 4.2% (1/24); and lymphoma, 4.2% (1/24). Favorable prognostic factors included: primary tumor less than 3 cm in size and absence of associated cirrhosis. These results emphasize that orthotopic liver transplantation can provide a long-term cure for approximately 50% of patients whose primary hepatic malignancy is unresectable by conventional procedures.


Assuntos
Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Adenoma de Ducto Biliar/mortalidade , Adenoma de Ducto Biliar/cirurgia , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrevida
7.
Transplantation ; 57(11): 1588-93, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8009592

RESUMO

Because of the almost universal recurrence of hepatitis B surface antigenemia (HBsAg) after liver transplantation, some centers have questioned whether these patients are appropriate allograft candidates. Since January 1984, 51 patients with hepatitis B (HBV) underwent OLT at our center. No therapy was given to prevent reinfection. Three patients underwent retransplantation. The indications for transplant included fulminant HBV (13 patients), chronic HBV (33 patients), and hepatocellular carcinoma (HCCA) in addition to HBV (5 patients). Incidental HCCA was found in 2 of the 33 patients thought to have only chronic HBV. Actuarial survival for the entire group was 57% at 1 year and 54% at 3 years. Of the 23 patients who died, only 4 deaths were attributable to recurrent HBV liver disease. Four patients survived less than 4 days due to primary graft nonfunction. Ten patients died in the first 3 months from sepsis. Although all patients who died beyond 30 days had recurrent HBsAg, only 4 deaths were attributable to recurrent HBV. The remaining 5 deaths were caused by portal vein thrombosis, bile leak, lymphoma, pancreatitis, and sepsis occurring at 15 months. Excluding the 4 patients who died from primary graft nonfunction, actuarial survival was 63% at 1 year and 60% at 3 years. Of the 28 survivors, 24 are HBsAg positive; however, only 5 have recurrent HBV liver disease. Multiple factors were evaluated to determine their influence on survival; i.e., HBV serology, United Network for Organ Sharing status, fulminant versus chronic HBV, incidence of rejection, immunosuppression, transfusion requirements, and presence of HCCA. Of these, only the presence of HCCA adversely affected outcome. Of the 7 patients with HCCA and HBV, 6 patients died within the first 6 months and 1 patient has recurrent HBV liver disease at 25 months. Actuarial survival excluding those patients with HCCA was 64% at 1 year and 61% at 3 years. Based on our results, patients with HBV and associated HCCA have a poorer prognosis and should probably be excluded from transplantation. Although the survival for patients with HBV undergoing liver transplantation is inferior to that expected in patients with some other diagnoses, long-term survival can be achieved in a majority of these patients despite recurrence of HBsAg. We believe that appropriately selected patients with a diagnosis of HBV alone should continue to be candidates for liver allografts.


Assuntos
Hepatite B/cirurgia , Transplante de Fígado , Adolescente , Adulto , Anticorpos Antivirais/análise , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Hepatite B/complicações , Hepatite B/mortalidade , Antígenos de Superfície da Hepatite B/análise , Vírus Delta da Hepatite/imunologia , Humanos , Lactente , Neoplasias Hepáticas/cirurgia , Masculino , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Homólogo
8.
Transplantation ; 58(3): 297-300, 1994 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8053050

RESUMO

Recent reports document the efficacy of transjugular intrahepatic portocaval shunts (TIPS) for the prevention of portal hypertensive bleeding and have advocated its use as a bridge to liver transplantation. There are no reports, however, analyzing liver transplant results for patients with indwelling TIPS. We reviewed the records of all adult primary recipients with a history of portal hypertensive bleeding or unmanageable ascites transplanted since the TIPS procedure became available in our institution in July 1991. Seven of 20 recipients underwent TIPS before transplant. There were no significant differences between patients with or without TIPS in age, United Network for Organ Sharing status, Child-Pugh score, preoperative prothrombin time, operative time, operative blood product requirement, overall length of stay, and 6-month patient survival after transplant. We noted a trend toward less operative red cell (26.0 +/- 26.2 vs. 31.8 +/- 38.1 U, mean +/- SD) and autologous blood (4,762 +/- 3,335 vs. 13,355 [corrected] +/- 20,460 ml) transfusion and improved patient survival for those with a TIPS. Patients with a TIPS in place waited significantly longer for their transplant (282 +/- 113 vs. 149 +/- 113 days, P = 0.014). There were 2 technical complications related to the TIPS, 1 in a patient who died after rupture of the suprahepatic vena caval anastomosis where the device had traversed the caval/hepatic vein junction and weakened the tissues, and the other in a survivor in whom the device extended into the right atrium and was extracted during the transplant procedure. Three patients with TIPS in place died of sepsis while waiting for a donor organ. We conclude that while the TIPS offers benefits for the liver transplant recipient, placement of the device in small shrunken cirrhotic livers must be precise. Immediate benefits for the transplant candidate may be offset by increased waiting time and technical complications at the transplant operation.


Assuntos
Transplante de Fígado/fisiologia , Derivação Portocava Cirúrgica/normas , Adulto , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Hemorragia Gastrointestinal/cirurgia , Humanos , Veias Jugulares/cirurgia , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Transplantation ; 43(1): 91-5, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3099442

RESUMO

A multiinstitutional randomized trial was undertaken comparing OKT3 with steroids for treatment of hepatic allograft rejection. All patients received baseline immunosuppression with Cyclosporine (CsA) and steroids. At the time of biopsy-confirmed rejection, up to 2 intravenous boluses (250-1000 mg) of methylprednisolone were initially administered. Twenty-eight patients who failed to respond were then randomly assigned to OKT3 or continued steroid therapy. Rescue therapy with the opposite treatment arm was added after 6 days if the primarily allocated protocol failed. Three of 13 patients assigned to the steroid group responded promptly, and continue with good function 7-12 months later. OKT3 rescue was required in 10 patients who failed to improve despite receiving up to 6 g of methylprednisolone (mean: 3.3 g/patient). One patient died of sepsis and hepatic failure. Rejection was reversed in 9 OKT3-rescue patients, 7 of whom are well 1-17 months later. In the OKT3 group, improved allograft function was observed within 72 hr in 11 of 15 patients. Two patients with inadequate response were successfully rescued with steroids; 1 patient underwent retransplantation; and 1 patient developed a biliary fistula that eventually resulted in sepsis and death. In summary, 23 of 28 hepatic recipients (82%) are alive with the original allograft 1-17 (mean 7.8) months after treatment for acute rejection. Another patient is alive 14 months following retransplantation. Eighteen (78%) of the survivors required OKT3 as initial (11) or rescue (7) therapy, whereas only 5 were successfully managed with steroids. OKT3 is superior to steroids for reversing liver allograft rejection and has greatly reduced the need for retransplantation even in recipients selected on the basis of having failed initial steroid therapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto/efeitos dos fármacos , Transplante de Fígado , Esteroides/uso terapêutico , Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T , Antígenos de Superfície/imunologia , Esquema de Medicação , Humanos , Fígado/imunologia , Hepatopatias/complicações , Hepatopatias/terapia , Metilprednisolona/uso terapêutico , Infecções Oportunistas/complicações
10.
Transplantation ; 63(11): 1595-601, 1997 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9197352

RESUMO

Cytomegalovirus (CMV) is a cause of considerable morbidity and mortality among orthotopic liver transplant (OLT) recipients. To study the impact of CMV on cost and hospital length of stay in this population, we undertook an analysis of a cohort of OLT recipients from four transplant centers in Boston who participated in a CMV prophylaxis trial. First posttransplant year hospital length of stay (including the hospital stay after transplantation and readmissions within 1 year after transplantation) was available for all 141 patients included in the study. In a multiple linear regression model bacteremia (P=0.0001), CMV disease (P=0.0007), abdominal reexploration (excluding retransplantation) (P=0.0070), recipient age < or = 16 years (P=0.0352), and the number of units of blood products (red blood cells, platelets, or fresh frozen plasma) administered during transplantation (P=0.0523) were shown to be independently associated with longer first posttransplant year hospital length of stay. Cost data for in-hospital care for the year beginning with admission for liver transplantation were available for 66 OLT recipients. Using a multiple linear regression model, development of CMV disease (P=0.0001), the number of units of blood products administered during transplantation (P=0.0001), bacteremia (P=0.0002), decreased pretransplant renal function (estimated by creatinine clearance) (P=0.0109), and need for retransplantation (P=0.0619) were shown to be independently associated with higher cost. These data strongly suggest that CMV disease has a direct impact on cost and hospital length of stay in liver transplantation.


Assuntos
Infecções por Citomegalovirus/complicações , Transplante de Fígado/economia , Adolescente , Adulto , Análise de Variância , Criança , Custos e Análise de Custo , Feminino , Humanos , Lactente , Tempo de Internação/estatística & dados numéricos , Transplante de Fígado/estatística & dados numéricos , Masculino , Análise Multivariada
11.
Transplantation ; 66(8): 1020-8, 1998 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-9808486

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection and disease has been found to be associated with decreased graft and patient survival among heart transplant recipients. We sought to explore the effect of CMV infection and disease on long-term survival in orthotopic liver transplant (OLT) recipients using a derivation and validation cohort. METHODS: For derivation-validation modeling, we used data collected from two prospectively followed cohorts as the basis for multivariate analyses: 167 OLT recipients from the Boston Center for Liver Transplantation (the derivation set; median follow-up: 5.5 years, mortality: 40%) and an independent cohort of 294 OLT recipients from the Mayo Clinic (the validation set; median follow-up: 4.8 years, mortality: 27%). RESULTS: Underlying liver disease other than primary biliary cirrhosis or sclerosing cholangitis, number of units of red blood cells administered during transplantation, and donor CMV seropositivity were the pre- and intratransplant variables independently associated (P<0.01) with decreased long-term survival in the derivation cohort. For variables collected up to 1 year after transplantation, the need for retransplan. tation, CMV pneumonia, invasive fungal disease, and underlying liver disease other than primary biliary cirrhosis or sclerosing cholangitis were independently associated (P<0.01) with decreased long-term survival in the derivation cohort. The magnitude of the relationship of each pre-, intra-, and posttransplant factor with survival, as measured by the relative risk, did not significantly differ between the derivation and validation cohorts. The derivation model, incorporating pre-, intra-, and posttransplant factors, had receiver operating characteristic areas of 73% and 74% for 5-year mortality in the derivation and validation cohorts, respectively. CONCLUSIONS: Data from a derivation and an independent validation cohort demonstrate that CMV factors (reflected by either donor CMV seropositivity at transplantation, CMV pneumonia, or CMV disease within the first posttransplant year) are independently associated with decreased long-term survival in OLT recipients.


Assuntos
Infecções por Citomegalovirus/fisiopatologia , Transplante de Fígado , Complicações Pós-Operatórias/fisiopatologia , Adolescente , Adulto , Estudos de Coortes , Feminino , Previsões , Humanos , Masculino , Análise Multivariada , Estudos Prospectivos , Análise de Sobrevida , Fatores de Tempo
12.
Transplantation ; 61(12): 1716-20, 1996 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-8685949

RESUMO

The incidence, predictors, and outcome of cytomegalovirus pneumonia in OLT recipients have not been well defined. We conducted an analysis of prospectively collected data from 141 OLT recipients who were included as part of a randomized, placebo-controlled trial of CMV immune globulin prophylaxis. Cytomegalovirus pneumonia was diagnosed in 13 of 141 (9.2%) OLT recipients during the first year posttransplant and was associated with a higher 1-year mortality compared with those recipients without CMV pneumonia (84.6 vs. 17.2%, P=0.0001). Univariate analysis demonstrated that CMV viremia (P=0.001), invasive fungal disease (P=0.0001), donor(+)/pretransplant recipient(-) CMV serologic status (P=0.013), abdominal operation (excluding retransplantation) after liver transplantation (P=0.0027), bacteremia (P=0.0105), and advanced United Network of Organ Sharing status (P=0.023) were associated with CMV pneumonia. Cytomegalovirus viremia was diagnosed in 11 of 13 patients with CMV pneumonia at a median of 11 days (range 1-66 days) before diagnosis of CMV pneumonia. In a multivariate analysis using a time-dependent, Cox proportional hazards model, CMV viremia (RR=8.6, 95% CI 1.8-39.7, P=0.0012), invasive fungal disease (RR=6.5, 95% CI 2.1-20.3, P=0.0001), and abdominal reoperation (RR=4.4, 95% CI 1.4-13.1, P=0.0043) were found to be independent predictors of CMV pneumonia. The attributable mortality associated with CMV pneumonia within the first year after liver transplantation for the patients with CMV pneumonia was 67.4%. Intensified measures for prevention of CMV should be considered for patients at high risk of developing CMV pneumonia.


Assuntos
Infecções por Citomegalovirus/etiologia , Transplante de Fígado , Pneumonia Viral/etiologia , Complicações Pós-Operatórias , Adulto , Análise de Variância , Antivirais/uso terapêutico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/prevenção & controle , Feminino , Seguimentos , Humanos , Imunoglobulinas/uso terapêutico , Imunoglobulinas Intravenosas , Incidência , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
13.
Transplantation ; 61(2): 235-9, 1996 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-8600630

RESUMO

Liver transplantation for patients requiring life-support results in the lowest survival and highest costs. A ten year (1983-1993) regional experience with liver transplantation for critically ill patients was undertaken to ascertain the fate of several subgroups of patients. Of the 828 liver transplants performed at six transplant centers within the region over this period, 168 (20%) were done in patients who met today's criteria for a United Network of Organ Sharing (UNOS) status 1 (emergency) liver transplant candidate. Recipients were classified according to chronicity of disease and transplant number (primary-acute, primary-chronic, reTx-acute, reTx-chronic). Overall one-year survival was 50% for all status 1 recipients. The primary-acute subgroup (n = 63) experienced a 57% one-year survival compared with 50% for the primary-chronic (n = 51) subgroup (P = 0.07). Of the reTx-acute recipients (n = 43), 44% were alive at one year in comparison with 20% for the reTx-chronic (n = 11) group (P = 0.18). There was no significant difference in survival for the following: transplant center, blood group compatibility with donors, age, preservation solution, or graft size. For patients retransplanted for acute reasons (primary graft nonfunction (PGNF) or hepatic artery thrombosis [HAT]), survival was significantly better if a second donor was found within 3 days of relisting (52% vs. 20%; P = 0.012). Over the study period progressively fewer donor organs came from outside the region. No strong survival-based argument can be made for separating, in allocation priority, acute and chronic disease patients facing the first transplant as a status 1 recipient. Clearly patients suffering from PGNF or HAT do far better if retransplanted within 3 days. Establishing an even higher status for recipients with PGNF, perhaps drawing from a supraregional donor pool, would allow surgeons to accept more marginal donors, thus potentially expanding the pool, without significantly compromising patient survival. Retransplantation of the recipient with a chronically failing graft who deteriorates to the point of needing life-support is nearly futile, and in today's health care climate, not an optimal use of scarce donor livers.


Assuntos
Transplante de Fígado/economia , Doença Aguda , Emergências , Planejamento em Saúde , Humanos , New England
14.
Transplantation ; 68(12): 1875-9, 1999 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-10628767

RESUMO

BACKGROUND: We report the consequences of a novel kidney allocation system on access of non-Caucasians (NC) to kidney transplantation. This new plan has provided a balance of allocation determinants between time waiting, HLA match, and geography (population density between donor and recipient center). METHODS: Three sequential systems of regional allocation were analyzed: period I (September 1994 to September 1996), period II (September 1996 to November 1997), and period III (December 1997 to March 1 1999). Periods II and III are reflective of the new allocation plan. RESULTS: During periods II and III, the NC rate of kidney transplantation increased closer to the NC proportion on the wait list, comparatively exceeding the national UNOS data. There was no statistical difference in regional mean wait time between Caucasian and NC. Improvements in access to transplantation for NCs between period I and periods II and III appear to be related to changes in geographic allocation weight from local unit to population density points, to the inclusion of the entire region in the plan, and to the deletion of intermediate degrees of B/DR mismatching in the revised plan. Despite the increased proportion of NCs on the wait list from period I to period III, the percentage difference between the proportion of NCs waiting on the list and the proportion NCs receiving a transplant fell from 7.8% to 4.9%. CONCLUSIONS: These data demonstrate that this new allocation plan was associated with improved access of minority candidates to transplantation. The broadening of geographic allocation and the alteration of HLA points appear to permit a more favorable opportunity for renal transplantation to NC candidates. selection, compared to the UNOS formula. In this report, we analyze the consequences of the Region 1 allocation system on the access of non-Caucasian (NC) candidates to cadaver donor kidney transplantation.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Transplante de Rim , Grupos Minoritários , Obtenção de Tecidos e Órgãos , Humanos , Listas de Espera , População Branca
15.
Transplantation ; 67(2): 303-9, 1999 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10075599

RESUMO

BACKGROUND: A novel plan of renal allograft allocation has been conducted by United Network for Organ Sharing Region 1 transplant centers since September 3, 1996, based upon HLA matching, time waiting, and population distance points. The objectives of this plan were to achieve a balance between increasing the opportunity of renal transplantation for those patients listed with long waiting times and promoting local organ donor availability. METHODS: A single list of candidates was formulated for each cadaver donor, assigning a maximum of 8 points for time waiting, a maximum of 8 points for population distance from the donor hospital, and HLA points based upon the degree of B/DR mismatch. Additional points were awarded to a cross-match-negative patient with a panel-reactive antibody of >80%, and to pediatric patients. RESULTS: The total number of kidneys transplanted to patients who had waited >3 years was 100 (46%), and to patients who had waited >2.5-3 years was 29 (13%). However, the total number of kidneys transplanted to patients with the maximum population distance points was only 72 (33%). Thus, although the plan achieved a favorable distribution of kidneys to patients with longer waiting times (nearly 60%), the other, equally important objective of promoting local donor availability was not initially accomplished. Moreover, minor HLA B/DR differences between the donor and the recipient (i.e., not phenotypically matched) were unexpectedly consequential in determining allocation. As a result of these observations, the following adjustments were made in the plan (as of December 3, 1997): a maximum of 10 points for population distance, a maximum of 8 points for time waiting (both by a linear correlation), and the retention of HLA points for 0 B/DR mismatch only. After these interval changes, the percentage of patients receiving a kidney with some population distance points increased from 85% to 96%. Conclusions. We have shown that a heterogeneous region of multiple transplant centers can devise (and modify) an innovative and balanced plan that provides an equitable system of allocation for an ever-increasing number of patients.


Assuntos
Transplante de Rim , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/organização & administração , Adolescente , Adulto , Cadáver , Criança , Teste de Histocompatibilidade , Humanos , Rim , Transplante de Rim/fisiologia , Transplante de Rim/estatística & dados numéricos , Preservação de Órgãos/métodos , Fatores de Tempo , Estados Unidos , Listas de Espera
16.
Transplantation ; 55(4): 802-6, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8475555

RESUMO

Hepatic retransplantation (reTx) offers the only alternative to death for patients who have failed primary hepatic transplantation (PTx). Assuming a finite number of donor organs, reTx also denies the chance of survival for some patients awaiting PTx. The impact of reTx on overall survival (i.e., the survival of all candidates for transplantation) must therefore be clarified. Between 1983 and 1991, 651 patients from the New England Organ Bank underwent liver transplantation, and 73 reTx were performed in 71 patients (11% reTx rate). The 1-year actuarial survival for reTx (48%) was significantly less than for PTx (70%, P < 0.05). This survival varied, dependent on the interval of time following PTx in which the reTx was performed (0-3 days, 57% survival; 4-30 days, 24%; 30-365 days, 54%; and > 365 days, 83%). Patients on the regional waiting list had an 18% mortality rate while awaiting transplantation. These results were incorporated into a mathematical model describing survival as a function of reTx rate, assuming a limited supply of donor livers. ReTx improves the 1-year survival rate for patients undergoing PTx but decreases overall survival (survival of all candidates) for liver transplantation. In the current era of persistently insufficient donor numbers, strategies based on minimizing the use of reTx, especially in the case of patients in whom chances of success are minimal, will result in the best overall rate of patient survival.


Assuntos
Transplante de Fígado/mortalidade , Modelos Biológicos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Transplante de Fígado/estatística & dados numéricos , Matemática , Pessoa de Meia-Idade , New England/epidemiologia , Reoperação/mortalidade , Reoperação/estatística & dados numéricos , Taxa de Sobrevida
17.
Transplantation ; 62(5): 594-9, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8830821

RESUMO

A multicenter trial was conducted to evaluate the efficacy and safety of tacrolimus in the treatment of refractory renal allograft rejection. Renal transplant recipients experiencing biopsy-proven recurrent acute allograft rejection were eligible if the current rejection episode was refractory to corticosteroids. A total of 73 patients were enrolled, of whom 59 (81%) had previously received at least one course of antilymphocyte antibody as rejection therapy. One-year follow-up was available in 93% of patients. Median time to tacrolimus rescue therapy was 75 days after transplantation (range, 18-1448 days). Therapeutic responses to tacrolimus included improvement in 78% of patients, stabilization in 11%, and progressive deterioration in 11%. The risk of experiencing progressive deterioration was related to the pretacrolimus serum creatinine level: serum creatinine < or = mg/dl, 3%; 3.1-5 mg/dl, 16% (P < 0.04); > 5 mg/dl, 23% (P < 0.02). Twelve-month (from the time of initiation of tacrolimus therapy) actuarial patient and graft survival rates were 93% and 75%. Graft loss occurred in 19 patients (25%) at a median time of 108 days. Fourteen episodes of recurrent rejection were diagnosed in 10 patients (14%), at a median time of 101 days. Eleven episodes of recurrent rejection were treated (three patients underwent transplant nephrectomy), with resolution achieved in nine patients. Antilymphocyte antibody therapy was not used to treat recurrent rejection. Serum creatinine values improved during tacrolimus therapy: median serum creatinine level before tacrolimus, 3.2 mg/dl; median at 1 year after tacrolimus, 1.8 mg/dl. Twelve infections were documented in 11 patients (15%), including cytomegalovirus infection in three patients (4%). Posttransplant lymphoproliferative disorder was diagnosed in a single patient. Tacrolimus whole blood levels averaged 15.0 +/- 9.9 ng/ml at day 7 of tacrolimus therapy and 9.4 +/- 5.1 ng/ml at 1 year, and were consistent among individual centers. Treatment outcome did not correlate with tacrolimus blood levels. The most commonly observed adverse events were neurological and gastrointestinal. Seventy-four percent of patients received tacrolimus for at least 1 year. Tacrolimus therapy was discontinued in 18% of patients for rejection (11% for progressive, unrelenting rejection, and 7% for recurrent rejection). Tacrolimus therapy was discontinued in 8% of patients due to adverse events. In conclusion, tacrolimus rescue therapy provides (1) prompt, effective reversal of refractory renal allograft rejection, (2) good long-term renal allograft function, (3) a low incidence of recurrent rejection, and (4) an acceptable safety profile in renal allograft recipients experiencing refractory rejection.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Tacrolimo/uso terapêutico , Doença Aguda , Adulto , Ciclosporina/uso terapêutico , Infecções por Citomegalovirus/etiologia , Resistência a Medicamentos , Estudos de Avaliação como Assunto , Feminino , Humanos , Imunossupressores/efeitos adversos , Transtornos Linfoproliferativos/etiologia , Masculino , Pessoa de Meia-Idade , Tacrolimo/efeitos adversos , Resultado do Tratamento
18.
J Nucl Med ; 16(10): 952-4, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1177028

RESUMO

The radioassay of very small 125I samples in both conventional and side-hole well crystals has been investigated. Using a multichannel analyzer, the source was counted at various positions within these well crystals. The effect of using a single-channel pulse-height analyzer was simulated by summing the counts over a 24-keV range across the primary peak, over a 30-keV range across the sum-coincidence peak, and over a 56-keV range across both peaks. In all crystals the primary peak was independent of sample position within the well over a range of several centimeters. The contribution of the sum-coincidence peak varied significantly with sample position in the conventional well crystals. With the side-hole crystal the counts contributed by the sum-coincidence peak exhibited a 2-cm plateau.


Assuntos
Radioisótopos do Iodo/análise , Contagem de Cintilação
19.
Chest ; 107(1): 218-24, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7813282

RESUMO

OBJECTIVE: To describe the hemodynamic and oxygen transport patterns in survivors and nonsurvivors following liver transplantation (LT) and to assess their relationship to organ failure and mortality. DESIGN: Retrospective cohort. SETTING: Surgical ICU in a tertiary care university teaching hospital. PATIENTS: Consecutive series of 113 adults undergoing LT between 1984 and 1992. Patients were excluded if they died intraoperatively (n = 2), required retransplantation (n = 8), or their records were incomplete (n = 7). MEASUREMENTS AND MAIN RESULTS: Preoperative severity of illness was assessed by the acute physiology and chronic health evaluation (APACHE) II scoring system. Hemodynamic and oxygen transport variables were recorded immediately preoperatively and sequentially every 12 h during the first 2 postoperative days. Organ failures (pulmonary, renal, cardiovascular, hepatic, and central nervous system) were assessed for patients in the postoperative period. Patients were grouped as survivors (n = 82) or nonsurvivors (n = 14) with a mortality rate of 15%. Preoperative APACHE II scores were significantly lower in survivors compared with nonsurvivors (7 +/- 0 vs 11 +/- 2; p = 0.029). Both preoperatively and postoperatively, survivors sustained a relatively higher mean arterial pressure, stroke volume index, left ventricular stroke work index, cardiac index, and oxygen delivery as compared with nonsurvivors (p < 0.01). The postoperative decline in systemic blood flow that was seen in both groups was particularly prominent in nonsurvivors during the first 12 h following LT (p < 0.03). Nonsurvivors sustained an approximately fivefold increase in the rate of organ failure (p < 0.0001); all patients (n = 6) with 4 or more organ failures died. CONCLUSION: Nonsurvivors of LT have less cardiac reserve pretransplant; postoperatively, they demonstrate early myocardial depression and subsequently lower levels of cardiac index and oxygen delivery. Patients who develop these hemodynamic patterns are more prone to organ failure and death.


Assuntos
Baixo Débito Cardíaco/etiologia , Hemodinâmica , Transplante de Fígado , Complicações Pós-Operatórias , APACHE , Adolescente , Adulto , Idoso , Baixo Débito Cardíaco/diagnóstico , Baixo Débito Cardíaco/fisiopatologia , Feminino , Humanos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Estudos Retrospectivos , Fatores de Risco
20.
Bone Marrow Transplant ; 20(3): 257-60, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9257897

RESUMO

Severe aplastic anemia (SAA) is a frequent complication of orthotopic liver transplantation for non-typeable viral hepatitis. Allogeneic bone marrow transplantation (BMT) may successfully reconstitute hematopoiesis but the optimal conditioning regimen and graft-versus-host disease (GVHD) prophylaxis in such patients are unknown. Allogeneic BMT was undertaken in an 8-year-old male patient who developed SAA 6 weeks after cadaveric orthotopic liver transplantation for fulminant hepatic failure secondary to presumed non-typeable viral hepatitis. The preparative regimen for his HLA genotypically identical sibling BMT consisted of cytoxan and anti-thymocyte globulin. Tacrolimus (FK506) and prednisone, used to prevent liver graft rejection, were supplemented with methotrexate on post-BMT days, 1, 3, 6 and 11 for GVHD prophylaxis. Engraftment proceeded promptly and without complications. Transfusion dependence resolved 6 weeks after BMT. The patient is alive and well 1 year after his BMT on FK506 and prednisone without any signs of GVHD or liver allograft rejection. This case is the first demonstration of the feasibility of continuing FK506 used for prevention of liver graft rejection as GVHD prophylaxis for allogeneic BMT.


Assuntos
Anemia Aplástica/terapia , Transplante de Medula Óssea , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Falência Hepática/terapia , Transplante de Fígado/efeitos adversos , Tacrolimo/uso terapêutico , Anemia Aplástica/etiologia , Criança , Humanos , Masculino , Transplante Homólogo
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