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Biomedical subjects

R Barcena

Publications and source records attributed to R Barcena.

At least 19 recordsLinked to original sources
PubMed2006

Hepatitis C recurrence after liver transplantation: Viral and histologic response to full-dose PEG-interferon and ribavirin.

Hepatitis C recurrence after liver transplantation (LT) is universal, and frequently leads to cirrhosis and death. The aim of our study was to assess the efficacy and safety of 48-weeks of full-dose peg-interferon-alpha-2a (n = 4) or alpha-2b (n = 51) plus ribavirin (>11 mg/kg/day) in a multicentric cohort of 55 patients > or =12 months after LT. All subjects had histologically proven HCV recurrence, excluding severe cholestatic recurrence. Mean age was 54.3 +/- 9.7, 77% male, 90.9% genotype 1, 32.7% cirrhotics. All but 5 patients received monotherapy with tacrolimus (54.5%), cyclosporine (30.7%) or mycophenolate mofetil (5.5%). The rates of end-of-treatment response and sustained virological response (SVR) were 66.7% and 43.6%, respectively. Low baseline HCV-RNA (p = 0.005) and a length from LT to therapy between 2-4 years (p = 0.011) were predictors of SVR. The lack of achieving a viral load decrease > or =1-log10 at week 4 and/or 2-log10 at week 12 was 100% predictive of failure. The most frequent side effects were neutropenia (76,4%), anemia (60%) and infectious complications (30.9%). Toxicity led to peg-interferon withdrawal in 16 (29%) subjects. In 15 patients with post-treatment biopsy, the histological activity index was significantly improved (p = 0.006), whereas fibrosis did not change (p = 0.14). Three patients died (cholangitis, hepatic artery thrombosis and lung cancer). In conclusion, HCV therapy after LT was very effective, although it led to a significant rate of toxicity.

Adolescent↗
PubMed2006

Scarce influence of corticosteroid boluses on long-term viral load and liver histology in transplanted patients with recurrent hepatitis C.

Corticosteroid boluses, which are the treatment for acute rejection episodes, have been shown to produce transient increases in viremia. However, their effect on long-term viral load, histological activity index (HAI), and fibrosis has not been well established. The aim of our study was to compare late viral load, HAI, and fibrosis in patients with versus without steroid boluses in the immediate posttransplant period. We analyzed patients transplanted due to hepatitis C virus. Inclusion criteria were: no change in immunosuppression (cyclosporine or tacrolimus with/without mycophenolate); no steroids in the previous 4 months; no antiviral treatment; liver biopsy and viral load determination >12 months after transplantation. Exclusion criteria were HIV, hepatitis B, and active cytomegalovirus infection. Nonparametric tests were used to compare viral load, HAI, and fibrosis (Ishak-score) among patients who received steroid boluses for an acute rejection episode (group 1) versus those who did not (group 2). Among the 48 selected patients were 38 men with the overall mean age of the entire group of 55.6 +/- 10.9 years. The mean period from liver transplantation was 53.25 +/- 33.4 months. Thirty-four (70.1%) were treated with tacrolimus and the rest, cyclosporine. Eleven (22.9%) had and 37 (77.1%) had not received corticosteroid boluses. The viral load was similar in groups 1 and 2 (5.74 +/- 0.54 vs 5.98 +/- 0.53 Log(10) IU per mL, P = .32). Fibrosis was also similar (2.5 +/- 1.6 vs 2.2 +/- 1.7, P = .56). However, HAI was higher in group 1 (7.5 +/- 1.7 vs 6.0 +/- 1.7, P = .026). In conclusion, although long-term viral load was similar in patients who had versus had not received one cycle of steroid boluses, the HAI was significantly higher in the former cohort, but had not resulted in greater fibrosis during the study follow-up.

Adrenal Cortex Hormones↗
PubMed2006

Hepatitis C virus recurrence after liver transplantation: influence of immunosuppressive regimens on viral load and liver histology.

Cyclosporine has recently been reported to produce in vitro suppression of hepatitis C virus replication driven by blockade of cyclophilins, an effect not shown for tacrolimus. However, the clinical consequence of this in vitro finding have not been well studied in vivo. We compared viral load and fibrosis in transplanted patients receiving monotherapy with tacrolimus or cyclosporine. Patients with recurrent hepatitis C after transplantation were selected from two tertiary centers with the following inclusion criteria: monotherapy with tacrolimus or cyclosporine for more than 12 months before viral load measurement, no antiviral treatment, corticosteroids stopped within 12 months after transplantation. HIV, hepatitis B, and active infection by cytomegalovirus were excluded. Patient characteristics, viral load, and fibrosis were compared by univariate analysis between the cyclosporine and tacrolimus groups. Significant variables, viral load, and fibrosis were included in a multivariate model. Sixty-six patients were included, 46 on tacrolimus and 20 on cyclosporine. Fifty-six were male, and the mean age was 55.3 +/- 10.1 years. Fibrosis (Ishak score) was 3.9 +/- 1.9 in the cyclosporine group and 2.7 +/- 1.9 in the tacrolimus group (P = .019). Viral load (log(10)IU/mL) was 5.8 +/- 0.5 and 5.9 +/- 0.5, respectively (P = .7) and time since liver transplantation was 95.3 +/- 47.7 and 41.1 +/- 16.8 months (P = .0001). In the multivariate model, viral load (P = .65) and fibrosis (P = .24) were not significantly different and only time since transplantation remained significant (P = .0001). In conclusion, viral load was not different in patients with tacrolimus as compared with cyclosporine, and the lower fibrosis observed in the cyclosporine group lacked significance when considered together with time since liver transplantation.

Aged↗
PubMed2005

Pegylated interferon and ribavirin for the recurrence of chronic hepatitis C genotype 1 in transplant patients.

The efficacy of pegylated interferon (p-IFN) and ribavirin (RB) in transplant patients is not well known. Chronic hepatitis C evolves in a more aggressive form after transplantation, causing a worse survival. Twenty-one naïve patients with recurrent chronic hepatitis C demonstrated by biopsy were treated for 48 weeks with p-IFN alpha2b (1.5 microg/kg/wk) and RB (>10.6 mg/kg/d). Quantification of RNA was performed (Amplicor Cobas 2.0 Roche) at baseline, 4, 12, 24, 48, and 72 weeks. A qualitative technique was used when quantitative levels were undetectable. At more than 1 year since liver transplantation we did not detect coinfection with human immunodeficiency virus or use steroid treatment. Among the cohort there were 16 men (76.2%). The mean overall age was 52 +/- 12 years. Time from liver transplant to treatment was 1637 +/- 1030 days. They were all infected with genotype 1. Eight patients received cyclosporine and the others tacrolimus. One patient was coinfected with hepatitis B virus and was receiving lamivudine. The mean initial histological activity index was 6.9 +/- 1.5 and fibrosis, 2.52 +/- 1.8 (Ishak). Two patients needed spleen embolization before the treatment. Two patients had to stop the treatment: one due to clinical intolerance, and the other one due to a cholangitis. In 14%, p-IFN doses were adjusted. In 32% RB was adjusted. Five (23.8%) did not respond at 24 weeks. Fourteen (66.7%) showed end-treatment responses but four relapsed at 72 weeks. A sustained viral response was achieved in 9 (42.8%). One patient died due to arterial thrombosis just after completing the treatment.

Adult↗
PubMed2004

Analysis of a quantitative PCR assay for CMV infection in liver transplant recipients: an intent to find the optimal cut-off value.

BACKGROUND: Preemptive therapy required highly predictive tests for CMV disease. CMV antigenemia assay (pp65 Ag) has been commonly used for rapid diagnosis of CMV infection. Amplification methods for early detection of CMV DNA are under analysis. OBJECTIVES: To compare two diagnostic methods for CMV infection and disease in this population: quantitative PCR (qPCR) performed in two different samples, plasma and leukocytes (PMNs) and using a commercial diagnostic test (COBAS Amplicor Monitor Test) versus pp65 Ag. STUDY DESIGN: Prospective study conducted in liver transplant recipients from February 2000 to February 2001. RESULTS: Analyses were performed on 164 samples collected weekly during early post-transplant period from 33 patients. Agreements higher than 78% were observed between the three assays. Optimal qPCR cut-off values were calculated using ROC curves for two specific antigenemia values. For antigenemia >or=10 positive cells, the optimal cut-off value for qPCR in plasma was 1330 copies/ml, with a sensitivity (S) of 58% and a specificity (E) of 98% and the optimal cut-off value for qPCR-cells was 713 copies/5x10(6) cells (S:91.7% and E:86%). Using a threshold of antigenemia >or=20 positive cells, the optimal cut-off values were 1330 copies/ml for qPCR-plasma (S 87%; E 98%) and 4755 copies/5x10(6) cells for qPCR-cells (S 87.5%; E 98%). Prediction values for the three assays were calculated in patients with CMV disease (9 pts; 27%). Considering the assays in a qualitative way, the most sensitive was CMV PCR in cells (S: 100%, E: 54%, PPV: 40%; NPV: 100%). Using specific cut-off values for disease detection the sensitivity, specificity, PPV and NPV for antigenemia >or=10 positive cells were: 89%; 83%; 67%; 95%, respectively. For qPCR-cells >or=713 copies/5x10(6) cells: 100%; 54%; 33% and 100% and for plasma-qPCR>or=1330 copies/ml: 78%, 77%, 47%, 89% respectively. CONCLUSIONS: Optimal cut-off for viral load performed in plasma and cells can be obtained for the breakpoint antigenemia value recommended for initiating preemptive therapy with high specificities and sensitivities. Diagnostic assays like CMV pp65 Ag and quantitative PCR for CMV have similar efficiency and could be recommended as methods of choice for diagnosis and monitoring of active CMV infection after transplantation.

Antigens, Viral↗
PubMed2001

Aspergillus antigenemia sandwich-enzyme immunoassay test as a serodiagnostic method for invasive aspergillosis in liver transplant recipients.

BACKGROUND: Invasive aspergillosis (IA) is an important cause of mortality in liver transplant patients. Clinical and microbiological diagnosis is difficult, and it is frequently achieved only after autopsy. Early diagnosis and antifungal therapy could improve the survival of these patients. METHODS: A retrospective case-control study of IA in liver transplant recipients (OLT) was performed to determine the value of the detection of galactomannan Aspergillus antigen in serum using a sandwich-ELISA test (Platelia, Sanofi Diagnostic Pasteur). Stored frozen serum specimens obtained during the posttransplantation period were used. RESULTS: Fourteen cases of IA were diagnosed in 240 OLT recipients (IA incidence: 5.8%) during 5 years with 13 deaths (mortality: 93%). Nine case patients and 33 control patients met the criteria required for being considered "valid" for antigenemia analysis. In five of the nine case patients, a serum sample was positive for Aspergillus antigenemia detection. The median value was 5.7 ng/ml (range: 1.6-6.6). Sensitivity of the test was 55.6%, specificity was 93.9%, the positive predictive value was 71.4%, and the negative predictive value was 88.6%. The likelihood ratio of a positive test was 9.2. CONCLUSIONS: Galactomannan detection in serum could be useful for an early diagnosis of IA in OLT recipients.

Adult↗
PubMed2001

Role of Helicobacter pylori infection and its eradication in patients with subclinical hepatic encephalopathy.

AIMS: Helicobacter pylori infection in cirrhotic patients has been associated with episodes of hepatic encephalopathy (HE), although conclusive data are still lacking. This prospective study has evaluated the prevalence of H. pylori infection in 37 patients with advanced cirrhosis of the liver and subclinical hepatic encephalopathy (SHE), diagnosed by changes in psychometric tests and/or electrophysiological tests, as well as the repercussion of H. pylori eradication on ammonaemia and the evolution of this disorder. RESULTS: A positive result for H. pylori infection was obtained in 22/37 (59%) patients. Initial fasting blood levels of ammonia were high in both groups. Infected and non-infected patients showed similar levels (62.05 mmol/l v. 62.5 mmol/l), which were lowered by the standard diet, although statistical significance was only reached in the infected patient group (53.05 +/- 26 mmol/l; P < 0.05). Infection was eradicated in 19 patients, but no reduction of blood levels of ammonia was observed after H. pylori eradication among infected patients (52.37 +/- 29 mmol/l). No change has been found in either group after the administration of diet or antimicrobials with regard to psychometric and/or electrophysiological tests. CONCLUSIONS: H. pylori infection does not contribute significantly to high blood levels of ammonia in patients with advanced cirrhosis and SHE. Likewise, H. pylori eradication does not induce any improvement in the psychometric and/or electrophysiological tests used to define SHE.

Adult↗
PubMed1994

Prevalence of antibodies to hepatitis C virus after blood transfusion in heart surgery.

We studied the frequency and time of appearance of antibodies to the hepatitis C virus (HCV) retrospectively in the sera of 127 patients who underwent heart surgery between 1983 and 1986. They received blood from volunteer donors hepatitis B surface antigen (HBsAg) negative with normal serum alanine-aminotransferase levels. A prospective follow-up was carried out every 15 days for at least 6 months from the moment of the transfusion. Of the ten patients who developed biochemical criteria of post-transfusional non-A non-B hepatitis, six seroconverted to anti-HCV (60%). Of the other 117, two were already positive before transfusion (1.51%), one patient showed antibodies only in the first post-transfusional serum (passive transfer), and another two patients with no evidence of post-transfusional hepatitis developed HCV antibodies on the 90th day, remaining indefinitely (afterwards seroconversion without hepatitis); both patients' earlier sera were anti-HCV negative. Four (40%) of the ten patients with post-transfusional hepatitis did not develop any serum markers to known hepatotropic agents. Although these findings do not exclude a viral infection by these viruses, they are consistent with the involvement of an unidentified non-A, non-B, non-C agent.

Blood Transfusion↗
PubMed1994

[Immunologic changes in chronic post-transfusion positive hepatitis C and non-A non-B non-C hepatitis].

OBJECTIVES: To study some aspects of the immunological abnormalities of C and non-A non-B non-C posttransfusional chronic hepatitis through the spontaneous and mitogen-stimulated "in vitro" production of immunoglobulins by peripheral blood lymphocytes. EXPERIMENTAL DESIGN: Peripheral blood lymphocytes from non-A non-B posttransfusional chronic hepatitis patients and from healthy volunteers were cultured in presence and absence of Pokeweed mitogen and the secreted immunoglobulins (IgG, IgA and IgM) were measured by ELISA in the supernatants. The results in both groups were compared. PATIENTS: 23 posttransfusional chronic hepatitis patients, 11 males and 12 females with an average age of 46.73 +/- 11.2 yrs (range: 24-69 yrs), have been studied. The histological diagnosis was chronic active hepatitis (CAH) in 13 cases, CAH with bridge necrosis in 6 patients and CAH with associated cirrhosis in 4 cases. The control group was composed by 11 healthy volunteers, 5 male and 6 female, with an average age of 38.45 +/- 12.77 yrs (range: 26-65 yrs). No one of the control group was positive for anti-HCV antibodies while in the posttransfusional chronic hepatitis patients group, 19 were positive and 4 negative. RESULTS: No significant differences in the spontaneous production of immunoglobulins between both groups has been found, however, when peripheral blood lymphocytes were stimulated with Pokeweed mitogen, a statistically significant lower production of immunoglobulins was observed in chronic hepatitis patients when compared with the control group. In non-A non-B posttransfusional chronic hepatitis patients, no relation has been found between the immunoglobulins production and histological findings or anti-HCV antibody titles. CONCLUSIONS: In the chronic phase of C and non-A non-B non-C posttransfusional chronic hepatitis, stimulated immunoglobulin production is significantly decreased for each immunoglobulin compared with the control group. These results suggest a failure in T-B lymphocyte cooperation in these infections since 82.6% of our patients were positive for HCV serological markers.

Adult↗
PubMed1994

[Prevalence of Helicobacter pylori infection in symptomatic adults].

AIM: To study the prevalence of Helicobacter pylori infection in different gastroduodenal entities in a wide group of symptomatic patients of our area. MATERIALS AND METHODS: 796 (493 females) patients referred to our Hospital for upper gastrointestinal endoscopy were studied. Mean age was 51.1 +/- 16.6 yrs. In all patients biopsies samples were taken from the gastric antrum for histological and microbiological (urease test) studies. A patient was considered Helicobacter pylori negative when its presence was not proved by microbiological and histological methods. RESULTS: 70.9% (73.8% males and 64.7% females) were Helicobacter pylori positive. The great majority of patients belong to 4. and 5. decade. Endoscopic diagnosis were: normal endoscopy 47.4%; antral gastritis 79.9%; pangastritis 68%; gastric ulcer 75.9%; duodenal ulcer 98.2%; pyloric ulcer 94.7%; endoscopic duodenitis 95.7%; gastric cancer 31.9%; operated stomachs 45.6%; and esophagitis 33.3%. CONCLUSIONS: The urease test had a high specificity (100%) and sensitivity (90%). Global results of H. pylori infection and its distribution among different gastroduodenal entities was similar to those described in other publications in our setting, although the prevalence was lower when compared with those countries with a lower socioeconomic status. H. pylori infection age-distribution suggests that this infection is acquired throughout life.

Adolescent↗
PubMed1993

[Treatment of hepatic and intra-abdominal hydatidosis with mebendazole: prospective comparison of the cyclic and the continuous regimen].

AIM: To communicate the results of two different schedules (cyclic and continuous) of mebendazole therapy for hepatic and intraabdominal hydatid disease. DESIGN: Prospective and randomized. PATIENTS: 26 cases of abdominal hydatid disease. RESULTS: No significant differences were registered between both groups. CONCLUSION: Cyclic mebendazole therapy does not improve the results of continuous treatment in abdominal hydatid disease.

Abdomen↗