Biomedical subjects

Martín Prieto

Publications and source records attributed to Martín Prieto.

13 recordsLinked to original sources

PubMed2006

Significant improvement in the outcome of HCV-infected transplant recipients by avoiding rapid steroid tapering and potent induction immunosuppression.

BACKGROUNDS/AIMS: Recurrent HCV-cirrhosis occurs in a substantial proportion of transplant recipients, with higher rates reported in patients who had recently received a transplant. Over-immunosuppression has been implicated in this more unfavorable outcome. To determine whether the implementation of specific measures aimed at reducing or avoiding negative predictive variables is associated with an improvement in the outcome of recurrent hepatitis C. METHODS: Comparative study between a cohort of patients who had recently received a transplant (2001-2004) and a historical group of HCV-infected patients transplanted before the implementation of two simple measures (1999-2000): (i) use of dual initial immunosuppression (steroids + cyclosporine neoral or tacrolimus); (ii) slow steroid tapering (>6 months). Yearly biopsies were performed in these recipients, and only those with at least one protocol biopsy and those with cholestatic hepatitis (regardless of follow-up) were included in the study. End-point: rate of HCV-related severe disease (defined as bridging fibrosis, cirrhosis or fibrosing cholestatic hepatitis) within the first year post-transplantation. RESULTS: Severe disease was significantly lower in this cohort compared to the historical group (26/90, 29% vs 25/52, 48%; p=0.02). While other factors remained unchanged between the two cohorts, the proportion of patients on triple-quadruple regimes and the number of boluses of methyl-prednisolone were lower and the duration of prednisone therapy longer in more patients who had recently received a transplant. CONCLUSIONS: Improving the outcome of recurrent hepatitis C may be achieved by reducing overall immunosuppression and avoiding abrupt variations in immunosuppression.

Adult↗

PubMed2006

Effect of calcineurin inhibitors on survival and histologic disease severity in HCV-infected liver transplant recipients.

The severity of recurrent hepatitis C virus (HCV) is likely related to several factors. Controversial results have been reported regarding the effect of specific calcineurin-inhibitors. The aim of this research was to determine whether there are differences on posttransplantation outcome in HCV-infected patients based on initial immunosuppression. Prospective randomized trial comparing tacrolimus vs. cyclosporine-based immunosuppression in a cohort of patients undergoing primary orthotopic liver transplantation between 2001 and 2003 was used. Yearly biopsies were performed. Patients with at least 1 protocol biopsy and those with very severe recurrence despite a follow-up of less than 1 yr (cholestatic hepatitis, progression to bridging fibrosis/cirrhosis) were included. Baseline characteristics (demographics, liver function at transplantation, genotype distribution, donor, surgery, immunosuppression except for the type of calcineurin inhibitor) did not differ between the 2 groups. Severe disease (defined as bridging fibrosis, cirrhosis, cholestatic hepatitis, and/or death due to recurrent disease in the first year) was present in 27 in 90 (30%), and was equally distributed in the cyclosporine and tacrolimus groups (15/46 vs. 12/44, respectively). A total of 33 in 90 (37%) patients had no fibrosis in the first year biopsy with no difference between the cyclosporine and tacrolimus groups (36.5 vs. 37%). The percentage of patients developing recurrent acute hepatitis was also similar (32% vs 35%); time to acute hepatitis though was shorter in the tacrolimus group (59 days [35-185] vs. 92 days [39-343] in the cyclosporin group; P = 0.02). Cholestatic hepatitis was observed in 4 of 44 and 5 of 46 patients under cyclosporine and tacrolimus, respectively (P = not significant). In conclusions, the short-term posttransplantation course of hepatitis C is not related to the calcineurin inhibitor used.

Adult↗

PubMed2006

Efficacy, predictors of response, and potential risks associated with antiviral therapy in liver transplant recipients with recurrent hepatitis C.

There are unresolved issues regarding sustained virological response (SVR), tolerance and risk of rejection following antiviral therapy in liver transplantation (LT). The aim of our study was to determine efficacy, rejection risk and factors associated with SVR. HCV-infected LT patients with at least 6 months of follow-up following end-of-therapy (EOT) received combination therapy of ribavirin (Rbvr) + standard (n = 31)/pegIFN (n = 36) between 1999 and 2004 (95% genotype 1). An EOT and SVR was obtained in 46% and 33%, respectively. Type of antiviral therapy, use of erythropoietin, compliance, and early virologic response (EVR) were predictive of SVR, but only the latter remained in the multivariate analysis. Premature discontinuation, not impacted by the use of erythropoietin or GCSF, occurred in 40% patients. None of the variables predicted rejection (acute n = 2, chronic n = 4). A SVR occurred in 3/4 patients with chronic rejection. In conclusion, the efficacy of pegIFN-Rbvr is similar to the non-transplant population. An EVR at 3 months is useful to predict lack of response. The type of calcineurin inhibitor and history of prior non-response to IFN before LT do not influence the outcome of therapy. Severe rejection may lead to graft loss, a complication difficult to predict.

Adult↗

PubMed2005

[Liver retransplantation: outcome analysis in 50 patients].

BACKGROUND AND OBJECTIVE: Liver re-transplantation (re-LT) is an accepted indication for some (technical problems, primary non-function [PNF]) but not all indications, particularly recurrence of the original disease, such as hepatitis C. We aimed to determine in our center: a) the rate of survival following re-transplantation for all and each different indication; b) to compare it to that obtained by a control group; c) to assess whether late re-LT, excluding PNF and surgical problems, and re-LT in HCV (+) patients are associated with a higher mortality, and d) to estimate medical costs. PATIENTS AND METHOD: Form 1991 to April 2002, 50 re-LT were done (group 1). Group 2 consisted of 45 primary LT controlled by transplant date. Group 1 was divided in two subgroups: a) re-LT after 6 months of the first LT (recurrence of primary liver disease n = 20, chronic rejection n = 5), b) Re-LT in the first 6 months (PNF n = 13, artery thrombosis n = 12). We analyzed donor, recipient, surgical and immunosuppressive-related variables. RESULTS: The mean age was 50 years (range: 23-63) (72% men). Actuarial survival for re-LT was lower than for the control group: 64%, 57% and 50% vs 84%, 82% and 82% at 1st, 3rd and 5th year, respectively. By indication, the 3-year survival was: PNF: 61% (p = 0.05), HAT: 58% (p = 0.02), recurrence of primary disease: 52% (p = 0.001), chronic rejection: 60% (p = 0.346). Although not reaching statistical significance, survival was lower in late vs early re-LT (p = 0.16) and in HCV-infected versus non-infected patients (p = 0.08). In the HCV (+) group, there were no differences by re-transplant indication (p = 0.8). Medical costs and complications were substantially higher in group 1 vs group 2. CONCLUSIONS: Re-LT is associated with substantial medical costs and mortality, particularly in patients infected with HCV.

Adult↗

PubMed2005

Prediction of fibrosis in HCV-infected liver transplant recipients with a simple noninvasive index.

Recurrent hepatitis C is a frequent event in liver transplantation (LT). Serial liver biopsies remain the best way of monitoring disease progression. Due to the limitations of a liver biopsy, there is an interest in developing noninvasive markers of liver fibrosis. While several models for predicting fibrosis have been constructed in patients who have not undergone transplantation, these are lacking in the transplant population. The aim of this study was to construct one simple model based on routine laboratory data to predict fibrosis in hepatitis C virus (HCV)-infected LT patients. A total of 510 yearly protocol liver biopsies performed in 188 LT patients (67% male; median age 54 years) were divided into 2 groups: training set (n = 414) and validation set (n = 96). Laboratory variables at time of biopsies were recorded. Multivariate analysis identified 4 variables as independent predictors of fibrosis: prothrombin time (PT), albumin/total protein ratio, aspartate aminotransferase (AST), and time since LT. The area under the receiver operating characteristic (ROC) curves (AUCs) were 0.80 and 0.84 for the training and the validation set, respectively. In the training set, using a cutoff of 0.2, the model had a sensitivity, specificity, positive predictive value, and negative predictive value of 74%, 69%, 42%, and 90%, respectively, to differentiate significant (bridging fibrosis and cirrhosis) from mild fibrosis (none or portal). In the validation cohort, these values increased to 87%, 71%, 49%, and 95%, respectively. In conclusion, in the LT setting, a simple fibrosis index is useful to select HCV-infected patients with a very low risk of significant fibrosis in whom protocol liver biopsies may be avoided.

Adult↗

PubMed2004

Genetic variability of hepatitis C virus NS3 protein in human leukocyte antigen-A2 liver transplant recipients with recurrent hepatitis C.

The association between the severity of chronic hepatitis C and the variability of the hepatitis C virus (HCV) genome remains controversial, but to our knowledge few data are available to date regarding T-cell epitope coding regions in transplant patients. In the current study, we identified 21 human leukocyte antigen (HLA)-A2-positive Spanish patients with chronic hepatitis C, 14 immunosuppressed liver transplant recipients, and 7 immunocompetent controls. Alanine aminotransferase, aspartate aminotransferase, viral load, and rate of fibrosis progression were determined. Genetic distances of HCV isolates and variations in epitopes of the HCV nonstructural 3 protein (NS3-1393 LIFCHSKKK and NS3-1406 KLVALGINAV) were compared between patients with slow or fast progression of fibrosis. Isolates from transplant patients with fast progression were found to be more divergent (P =.03), had a higher mean value of synonymous (dS) variations (P =.02), and some were differentiated in a phylogenetic tree, compared with isolates from patients with slow progression. The HLA-A2-restricted NS3-1406 epitope was found to be more variable (20 of 21 isolates differed from the prototype) compared with the A3-restricted NS3-1392 epitope (19% vs. 1.25% variation). A shift in the viral peptide was not detected in a subset of transplant patients, but was evident in two of three nontransplant patients with follow-up. There was no correlation noted between a particular amino acid variation and fibrosis progression (slow or fast) in either transplant or nontransplant patients. The results of the current study suggest that 1) there may be different HCV-1b strains in our geographic area, 2) immunosuppression appears to have little effect in amino acid variation at the HCV NS3-1406 epitope, and 3) variations over time might be more frequent in nonimmunosuppressed patients.

Adult↗

PubMed2004

Recurrent hepatitis C genotype 1b following liver transplantation: treatment with combination interferon-ribavirin therapy.

BACKGROUND: Recurrent hepatitis C is very common leading to graft cirrhosis in a significant proportion of patients. Preliminary reports of combination therapy with interferon-ribavirin have been promising but generally applied to selected patients with chronic mild disease. Little is known, however, about the efficacy and risk of adverse effects when it is used in general clinical practice. AIMS: To analyse the efficacy (biochemical, virological and histological response) and tolerance of combination therapy in patients with recurrent hepatitis C genotype 1b. METHODS: Twenty-four patients (mean age 54 years; range 37-67 years; 75% male) with recurrent hepatitis C virus (histology at baseline: acute hepatitis (n = 3); chronic hepatitis (n = 21) with F3 or 4 in 77%) were treated with 12 months interferon (1.5-3 MU thrice weekly) + ribavirin (600-1200 mg daily) followed by 6 months ribavirin (58%), at a median of 427 days (56-2812) after transplantation. RESULTS: Seven patients (29%) discontinued therapy due to side effects, mainly anaemia, at a median of 3 months since initiation. Dose modifications were required in 88% of those completing the whole course of therapy. Overall, the sustained virological and biochemical response was 12.5%. This rate was slightly higher (18%) if only the 17 patients who finished the whole course of therapy were analysed. Histological improvement was achieved in 31.5% of treated patients. CONCLUSIONS: Combination therapy has a very limited efficacy in the liver transplant setting, although some benefit may be achieved, even in those with advanced graft fibrosis. Tolerance, however, remains a matter of concern.

Acute Disease↗

PubMed2004

De novo internal neoplasms after liver transplantation: increased risk and aggressive behavior in recent years?

The goal of the study was to determine the incidence and variables associated with post-liver transplantation (LT) de novo internal neoplasms development, excluding skin tumors and hepatocellular carcinoma. Medical records were reviewed for recipient/donor demographics, viral serology, cause of liver disease, interval from LT to tumor diagnosis, predisposing factors, immunosuppression and survival. Forty-one neoplasms (31 solid and 10 hematologic) developed in 772 recipients (5.3%) transplanted between 1991 and 2001. Time to tumor diagnosis was longer in patients transplanted before 1995 than in those transplanted afterwards (58 vs. 22 months; p<0.05). Hematologic neoplasms (HN) appeared earlier than solid (2 vs. 21 months; p<0.001), were more prevalent in those transplanted after 1995 than before (32% vs. 12.5%), and had lower survival than solid (2 vs. 21 months, p<0.001). While HCV was the most frequent indication in HN (70%), alcohol was that of solid tumors (71%). Overall, risk factors for de novo neoplasms included alcohol and immunosuppression (p<0.01). In patients undergoing LT in recent years, there is a higher incidence of HN with de novo internal neoplasms developing at earlier time-points than in those transplanted years ago. Risk factors for tumor development include alcohol, HCV and possibly strong immunosuppression.

Adult↗

PubMed2003

[Hemolytic anemia due to ABO or Rh antibodies in recipients of solid organ transplants].

BACKGROUND AND OBJECTIVE: Hemolysis due to ABO or Rh unmatched transplants in solid organ recipients owes to the passage of lymphocytes with immunologic information. The development of antibodies and hemolysis is directly related to the amount of lymphocytes that goes with the transplanted organ. We present five cases of hemolytic anaemia, 2 by ABO and 3 by Rh systems. PATIENTS AND METHOD: From January 1991 to June 2001, 22 liver transplants ABO-unmatched, 236 renal transplants Rh-unmatched and 240 liver transplants Rh-unmatched were performed in our center. Both in donors and recipients, we performed an hematologic study with determination of indirect antiglobulin test (IAT). When IAT was positive, the antibody was determined through different methods. If hemolysis was suspected after transplantation, direct antiglobuline test (DAT) and antibody specifity were determined. RESULTS: Two liver transplants ABO-unmatched and three Rh-unmatched developed hemolysis. It was severe in all them and appeared between the 8th and 40th post-transplant day. Screening for irregular antibodies was negative in all pre-transplant patients. In donors, anti-D was recognized in two cases. Among post-transplant patients, DAT and IAT were positive in all them, anti-A was found in two, anti-D in two and anti-E in one case. All patients were treated with IV steroids. Four required transfusion with compatible packed red blood cells. CONCLUSION: Hemolysis in the context of a solid organ transplantation with minor unmatched ABO or Rh must alert us about the possibility of passage of donor lymphocytes.

ABO Blood-Group System↗

PubMed2003

A randomized study comparing lamivudine monotherapy after a short course of hepatitis B immune globulin (HBIg) and lamivudine with long-term lamivudine plus HBIg in the prevention of hepatitis B virus recurrence after liver transplantation.

BACKGROUND/AIMS: To compare the efficacy in preventing hepatitis B virus (HBV) recurrence of lamivudine vs. lamivudine plus hepatitis B immune globulin (HBIg) after a short course of HBIg and lamivudine in liver transplanted chronic hepatitis B patients. METHODS: Forty-six patients with HBV cirrhosis received lamivudine before liver transplantation and were then randomized to receive lamivudine plus HBIg for 1 month followed by lamivudine or both drugs for 17 months. RESULTS: Thirty-two patients were transplanted and 29 were randomized to receive combination therapy (15 cases) or lamivudine monotherapy (14 cases). HBV DNA was undetectable in all cases (17 induced by lamivudine therapy) at the time of liver transplantation. After 18 months of follow-up, all patients survived without HBV recurrence: hepatitis Bs antigen and HBV DNA were negative; however, HBV DNA was detected by polymerase chain reaction in four cases (three with HBIg plus lamivudine and one with lamivudine). Alanine aminotransferase levels were normal except in six cases (one HCV and two HDV coinfections). There were no drug-related adverse events. CONCLUSIONS: Lamivudine monotherapy after a short course of lamivudine and HBIg is equally as efficacious in preventing HBV recurrence as HBIg plus lamivudine during the first 18 months after liver transplantation. This strategy is more economic and convenient to administer than long-term HBIg plus lamivudine.

Adolescent↗

PubMed2003

Severe recurrent hepatitis C after liver retransplantation for hepatitis C virus-related graft cirrhosis.

An increase in the number of hepatitis C virus (HCV)-infected transplant recipients at need for repeated liver transplantation is anticipated. To date, there is a certain reluctance to accept these patients because of an increased organ shortage, early reports suggesting a poor outcome, and uncertainty regarding the natural history of recurrent hepatitis C in the second graft. The aim of this study is to determine the outcome of patients undergoing retransplantation for HCV-related graft cirrhosis. Of 49 transplant recipients with HCV-related allograft cirrhosis, 31 patients developed decompensation with criteria for retransplantation. Thirteen patients were denied this option. Of the 18 patients accepted, 6 patients died while on the waiting list (5 patients died of graft cirrhosis at a median of 3.2 months of listing), and 12 patients have undergone retransplantation (median, 10 months since HCV cirrhosis). After retransplantation, 8 patients (67%) died at a median of 8 months, and 4 patients (33%) remain alive after 1.9 years of follow-up. Causes and times of death from retransplantation were: surgical complications, n = 3 (perioperative period); HCV cirrhosis of the second graft, n = 2 (at 9 and 54 months); fibrosing cholestatic hepatitis, n = 1 (at 2 years); lymphoproliferative disorder, n = 1 (at 7 months); and endocarditis, n = 1 (at 3.5 years, with underlying cirrhosis). Of the 4 patients alive, fibrosis stages in the last biopsy specimens are stage 1 (n = 1), stage 3 (n = 1), and stage 4 or cirrhosis (n = 1; one patient has not undergone biopsy), despite antiviral therapy. The outcome of retransplantation for HCV cirrhosis of the first graft is very poor because of multiple complications. The severity of recurrent HCV disease in the second graft seems to be related to that observed in the first graft.

Adult↗

PubMed2002

Contribution of donor age to the recent decrease in patient survival among HCV-infected liver transplant recipients.

Recurrent hepatitis occurs in the majority of patients undergoing liver transplantation for hepatitis C virus (HCV) cirrhosis, with progression to cirrhosis in up to 30% after 5 years. Based on these data, a decrease in survival can be anticipated with prolonged follow-up. Furthermore, posttransplantation HCV-fibrosis progression has been shown in recent years to increase. Our aims were (1) to describe the natural history of HCV-infected recipients, particularly to determine whether survival has decreased in recent years; (2) to compare this outcome with that observed in non-HCV-infected cirrhosis controls; and (3) to determine the factors associated with disease severity and survival. Among 522 cirrhotic patients undergoing transplantation between 1991 and 2000, 283 (54%) were infected with HCV. Yearly biopsies were performed in these recipients and at 1 and 5 years in the remainder. With similar follow-up, the percentage of deaths in the HCV(+) group was significantly higher than in the HCV- group (37% vs. 22%, P <.001), and patient survival was lower (77%, 61%, 55% vs. 87%, 76%, 70% at 1, 5, and 7 years, respectively; P =.0001). Although survival has increased in the HCV- group in recent years, it has significantly decreased in HCV recipients (P <.0001). The main cause of death among the latter was decompensated graft cirrhosis (n = 23/105, 22%), whereas that of HCV- patients was infections (n = 10/52, 19%). Reasons for the recent worse outcome in HCV+ recipients include the increased donor age and stronger immunosuppression. In conclusion, patient survival is lower among HCV+ recipients than among HCV- ones and has been decreasing in recent years. The aging of donors is a major contributor to this worse outcome.

Adult↗

PubMed2002

Hepatocellular carcinoma: Can it be considered a controversial indication for liver transplantation in centers with high rates of hepatitis C?

Hepatocellular carcinoma (HCC) is still considered a controversial indication for liver transplantation (LT), mainly because of long waiting times and underlying viral cirrhosis. The goal was to evaluate the outcome of LT in 104 patients with HCC and cirrhosis, mainly hepatitis C virus (HCV)-related, in a center with a short waiting time (median, 105 days). Four groups were formed according to the HCC and HCV status: HCV positive with HCC (group 1, n = 81), HCV negative with HCC (group 2, n = 23), HCV positive without HCC (group 3, n = 200), and HCV negative without HCC (group 4, n = 207). Predictive factors of tumor recurrence were demographics, tumor related (size or number of nodules, capsule, bilobar involvement, vascular or lymphatic invasion, clinical and pathologic TNM staging, pre-LT percutaneous ultrasound-guided ethanol injection or transarterial chemoembolization, alpha-fetoprotein levels), donor and surgery related, and year of transplantation. The same variables and "tumor recurrence (yes/no)" were applied to evaluate the effect on survival. The median follow up was 29 months (range, 0 to 104 months). Patient survival was 70% at 1 year and 59% at 5 years for group 1, 87% at 1 year and 77% at 5 years for group 2, 81% at 1 year and 64% at 5 years for group 3, and 88% at 1 year and 77% at 5 years for group 4 (P =.013). Survival was significantly lower in patients with HCC than in those without (74% and 63% versus 85% and 70%, at 1 and 5 years, respectively; P =.05). The causes of death in those with and without HCC were tumor recurrence (24%) and recurrent HCV (8%) versus sepsis (34%) and recurrent HCV (14%). HCC recurrence occurred in 12 patients (11.5%) at a median of 14 months (range, 3 to 60 months) with a probability increasing from 8% at 1 year to 16% at 5 years. In patients with HCC, tumor recurrence was associated with vascular invasion (P =.0004) by multivariate analysis; variables predictive of survival were donor old age (P =.01), viral-related etiology (P =.02), and tumor recurrence (P =.001). Although LT still remains an adequate indication for HCC in centers with high prevalence of HCV infection and short waiting times, both tumor and HCV-related recurrent diseases hamper significantly the outcomes of these patients.

Adult↗