RESUMEN

Recurrent hepatitis C virus (HCV) remains a problematic cause of morbidity and mortality for liver transplant patients. Immunosuppression including calcineurin-inhibitors has been implicated in the acceleration of recurrent HCV. Recent studies suggest that outcomes may be better with cyclosporine (CSA-ME) compared to tacrolimus (TAC), but the data are inconclusive. We retrospectively analyzed data received from the United Network for Organ Sharing on 8809 chronic HCV liver transplant recipients receiving either cyclosporine microemulsion (CSA-ME) or tacrolimus (TAC) as maintenance immunosuppression prior to discharge. We analyzed patient death, graft failure, failure due recurrent disease and acute cellular rejection (ACR) for CSA-ME versus TAC treated patients. Three-year unadjusted patient and graft survival rates were 76.8% and 71.5%, respectively, in the CSA-ME group versus 79.9% and 75.0% in the TAC group. Propensity score-adjusted results suggest CSA-ME treated patients are at increased risk of patient death and graft failure [Hazards ratio (HR) = 1.17; 95% CI = 1.01-1.36 and HR = 1.19; 95% CI = 1.04-1.35, respectively] and biopsy-confirmed AR (HR = 2.03; 95% CI = 1.54-2.67) compared to TAC treated patients. These results provide evidence to reconsider the targeted administration of CSA-ME to HCV-infected liver transplant recipients.

Asunto(s)

Asunto(s)

RESUMEN

Delayed graft function (DGF) impacts short- and long-term outcomes. We present a model for predicting DGF after renal transplantation. A multivariable logistic regression analysis of 24,337 deceased donor renal transplant recipients (2003-2006) was performed. We developed a nomogram, depicting relative contribution of risk factors, and a novel web-based calculator (http://www.transplantcalculator.com/DGF) as an easily accessible tool for predicting DGF. Risk factors in the modern era were compared with their relative impact in an earlier era (1995-1998). Although the impact of many risk factors remained similar over time, weight of immunological factors attenuated, while impact of donor renal function increased by 2-fold. This may reflect advances in immunosuppression and increased utilization of kidneys from expanded criteria donors (ECDs) in the modern era. The most significant factors associated with DGF were cold ischemia time, donor creatinine, body mass index, donation after cardiac death and donor age. In addition to predicting DGF, the model predicted graft failure. A 25-50% probability of DGF was associated with a 50% increased risk of graft failure relative to a DGF risk < 25%, whereas a > 50% DGF risk was associated with a 2-fold increased risk of graft failure. This tool is useful for predicting DGF and long-term outcomes at the time of transplant.

Asunto(s)

RESUMEN

Wilson's disease is a hereditary defect in copper excretion leading to the accumulation of copper in the tissues, with subsequent tissue damage. The most serious sequela is that of progressive central nervous system involvement. The use of orthotopic liver transplantation (OLT) has been controversial for those patients with neurological symptoms attributed to Wilson's disease. The aim of this study is to determine the effectiveness of OLT for patients with Wilson's disease, including those with neurological involvement attributed to copper accumulation in the central nervous system. OLT was performed in 45 patients (19 men [42.2%], 26 women [57.8%]) with Wilson's disease between 1971 and 1993 who were followed up for at least 4 years. The age at diagnosis of Wilson's disease ranged from 3 to 41 years (mean, 17.7 +/- 7.4 years). The age at OLT ranged from 8 to 52 years (mean, 22.3 +/- 9.4 years). Nineteen patients (42.2%) were aged younger than 18 years at OLT. The indications for OLT included chronic hepatic failure in 15 patients (33.3%) and fulminant (FHF) or subfulminant hepatic failure in 30 patients (66. 6%). All but 1 of the 19 pediatric patients (94.7%) were in the latter group. Twenty-five patients (55.5%) were receiving D-penicillamine, 9 patients for more than 1 year; none of the patients treated long term presented as FHF. Thirty-three patients (73.3%) survived more than 5 years after OLT. Fourteen patients (31%) died during the posttransplantation period; 7 of the 14 patients (50%) were aged younger than 18 years. Twelve patients died during the first 3 months after OLT of complications of disease and surgery, 10 of whom underwent transplantation for FHF. The other 2 patients died 6 and 9 years after transplantation of infectious problems. Eleven patients (24.4%) required retransplantation because of a primary nonfunctioning graft (n = 6), chronic rejection (n = 4), and hepatic artery thrombosis (n = 1). Seventeen patients (37.7%) presented with neurological abnormalities; 14 patients with Wilsonian neurological manifestations and 3 patients with components of increased intracranial pressure. Ten of the 13 surviving patients with hepatic insufficiency and neurological abnormalities at OLT showed significant neurological improvement. Our experience shows OLT is a life-saving procedure in patients with end-stage Wilson's disease and is associated with excellent long-term survival. The neurological manifestation of the disease can improve significantly after OLT. Earlier transplantation in patients with an unsatisfactory response to medical treatment may prevent irreversible neurological deterioration and less satisfactory improvement after OLT.

Asunto(s)

RESUMEN

A novel bioequivalence testing approach was used to determine intrasubject variability and switchability of two ciclosporin formulations, SangCya (test) and Neoral (reference). Twenty healthy volunteers were enrolled into a single-dose, randomized, open-label, 4-period, 2-sequence study with a crossover replicate design. Subject-by-formulation interaction variances were compared using a mixed effects linear model. Intrasubject variability for ln AUC(0-infinity) and ln C(max) of SangCya and Neoral were not significantly different. The 95% confidence intervals of the intrasubject variability of AUC(0-infinity) (0.94) and C(max) (1.28) as determined using the bootstrap nonparametric percentile method (n = 2,000) were below the individual bioequivalence limit estimated at 2.25. We concluded equivalent intrasubject variability of ciclosporin pharmacokinetics and switchability between SangCya and Neoral.

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

Legionella pneumophila is an important pathogen that may cause nosocomial and community-acquired pneumonia in patients with normal or altered immunity. The epidemiology of 40 cases of legionella pneumonia in patients hospitalized between 1986 and 1994 was studied. Fourteen patients (35%) were solid organ transplant recipients. The calculated annual incidence of L. pneumophila infection was highest among lung transplant recipients (2.07 cases per 1,000 transplant-years). There was a trend toward reduced mortality rates and less severe disease among transplant patients vs. nontransplant patients: mortality rate, 36% vs. 54%; incidence of intubation, 50% vs. 69%; rate of concurrent infections, 29% vs. 38%; and overall rate of complications, 86% vs. 96%; respectively. In a multivariate analysis, factors independently associated with an increased mortality rate were nosocomial acquisition, need for intubation, formation of lung abscess or cavitation, and presence of pleural effusion. Thus, despite differing host immune responses, the most important prognostic factors affecting the outcome of legionellosis are nosocomial acquisition and the development of pulmonary complications.

Asunto(s)

RESUMEN

Between January 1987 and October 1991, 1466 patients underwent consecutive Orthotopic Liver Transplantation (OLTx) at the University of Pittsburgh. Forty of these patient's had concomitant splenectomy with OLTx. These patients were compared to 147 randomly selected OLTx patients without splenectomy within the same time period. One-year patient and graft survival (PS and GS) were lower in splenectomized (Splx) patients compared to nonsplenectomized (non-Splx) patients (59% vs 86% PS, 55% vs 80% GS, respectively). One-month and one-year patient mortality in the Splx group was higher than in the non-splx patients (20% vs 3.4%, P < 0.001 for one month; 40% vs 14.3%, P = 0.003 for one year, respectively). One-month and one-year sepsis-related mortality was also high in Splx patients (17.5% vs 2.7%, P = 0.0022, for one month, and 30% vs 11.5%, P = 0.0043, for one year, respectively). We conclude that concomitant splenectomy with OLTx has a significantly higher patient mortality mainly due to its septic complications and, at present, unless there is a specific indication for a splenectomy, the routine addition of this procedure to liver allograft surgery would not be recommended.

Asunto(s)

RESUMEN

PURPOSE: To help investigators decide if new therapies for glioma warrant definitive evaluation in randomized studies we have been developing a method for assessing the degree to which patient selection may have enhanced the results of uncontrolled treatment trials. In this study, we analyzed the impact of case selection on the survival of patients with malignant glioma receiving adjuvant stereotactic radiosurgery, a promising therapy reserved for those with small tumors and good performance status. METHODS: Following published eligibility criteria we simulated the patient selection process for stereotactic radiosurgery given as a boost at the conclusion of conventional radiotherapy. Eligible patients were culled from a pre-existing clinical/imaging database of 101 consecutive conventionally-treated patients with biopsy-proven malignant glioma and known survival times. Median durations of survival and 2- and 3-year survival rates were determined for those judged eligible or ineligible for stereotactic radiosurgery. RESULTS: Twenty-seven percent of patients were deemed eligible for stereotactic radiosurgery, eligible patients had more favorable prognostic factors and significantly longer median survival than ineligible patients (23.4 vs. 8.6 months; 2-year rate, 48% vs. 15%; 3-year rate, 30% vs. 7%); eligible patients also had a longer median survival than the entire group of unselected patients (23.4 vs. 11.4 months). Radiosurgery-eligible, conventionally-treated patients with glioblastoma multiforme and a group of radiosurgery-treated patients at a special referral center had similar median survival times (16.4 vs. 19.7 months). CONCLUSION: We provide additional evidence for selection bias in uncontrolled trials of stereotactic radiosurgery and by simulating the selection process accurately have detected a larger bias effect than noted previously. Judging from experience with interstitial radiation and intraarterial chemotherapy where substantial selection bias also occurred and randomized controlled trials proved disappointing, we conclude that a phase III study of stereotactic radiosurgery for malignant glioma is unlikely to yield a positive result and may not be necessary.

Asunto(s)

Asunto(s)

RESUMEN

FK 506 was used as a primary immunosuppressive agent in 125 cases of renal transplantation in a randomized trial comparing FK 506/prednisone with FK 506/azathioprine/prednisone. With a mean follow-up of 5.5 +/- 2.5 months, there has been a 6-month actuarial patient survival of 99% and graft survival of 88%. There is no difference thus far between the two-drug and three-drug groups, although there may be less rejection and diabetes in the three-drug group. These results suggest that FK 506 is a useful immunosuppressive agent in kidney transplantation.

Asunto(s)

RESUMEN

Interstitial irradiation is a promising treatment for malignant glioma. Longer than expected survival periods following treatment of recurrent tumor have led to the use of brachytherapy as an adjuvant treatment. The impact of patient selection on survival data was studied among candidates for this therapy. Consecutive, conventionally treated adults with newly diagnosed supratentorial tumors were identified retrospectively at a center where experience with glioma is population-based. Based on imaging and performance status, two surgeons and a radiation oncologist designated each patient as either eligible or ineligible for adjuvant brachytherapy. The survival and prognostic factors in the eligible and ineligible groups were analyzed. Overall, the patients eligible for brachytherapy (32% of the series) lived significantly longer than the ineligible patients (16.57 vs. 9.30 months), were younger, and had larger resections and better function. For glioblastoma, 40% of patients were eligible, and lived much longer than those who were ineligible (13.90 vs. 5.80 months). It is concluded that better outcome following adjuvant brachytherapy for glioma is at least in part the result of patient selection. Randomized trials of comparably selected patients will be necessary to demonstrate conclusively that longer survival is also a result of treatment.

Asunto(s)

Asunto(s)

RESUMEN

When an automatic defibrillator is implanted, it is essential to determine the efficacy of the defibrillating system accurately, while balancing the need to keep the number of fibrillation episodes to a minimum. Two methods have evolved to assess defibrillation efficacy: 1) the "defibrillation threshold," which requires few ventricular fibrillation episodes, and 2) the "dose-response curve," which requires many ventricular fibrillation episodes and relates percent success to energy. The purpose of this study was to compare these two methods directly. Twenty open-chest anesthetized pigs had triplicate defibrillation threshold determinations. To produce a dose-response curve, six shocks then were delivered at 0.5, 0.75, 1.0, 1.25, 1.5, and 2.0 times the mean defibrillation threshold, in a balanced randomized order, during separate episodes of ventricular fibrillation. The data were fitted by logistic regression, conversions of the logistic regression, and a saturable exponential and nonsaturable growth exponential. A comparison was made of the mean defibrillation threshold and the 50% point on the dose-response curve (ED50) for each model, for each animal. In addition, the reliability of each measure was assessed by comparing the coefficients of variation. There was no statistical difference between the group defibrillation threshold (6.6 +/- 0.5 J) and group ED50 values (ED50 range of the models, 5.7 +/- 1.9 to 7.0 +/- 0.9 J). However, the variability about the defibrillation threshold was less than that of the ED50 values for all mathematical models except the true logistic equation, which was virtually the same.(ABSTRACT TRUNCATED AT 250 WORDS)

Asunto(s)