Prevalence of non-alcoholic fatty liver disease and liver fibrosis in a general population cohort from Argentina.

INTRODUCTION AND OBJECTIVES: South America is one of the regions with the highest rates of non-alcoholic fatty liver disease (NAFLD). This study aimed to assess the prevalence and severity of NAFLD in suburban Argentina. PATIENTS AND METHODS: The study involved a general community cohort of 993 subjects evaluated sequentially with a comprehensive lifestyle questionnaire, laboratory testing, abdominal ultrasound (US) and transient elastography with XL probe. NAFLD was diagnosed according to standard criteria. RESULTS: The prevalence of NAFLD by the US was 37.2% (326/875) overall, 50.3% in subjects with overweight/obesity, 58.6% with hypertriglyceridemia, 62.3% with diabetes/hyperglycemia and 72.1% with all three risk factors. Male gender (OR 1.42, 95% CI 1.03-1.47, p = 0.029), age (50-59 years: OR 1.98, 95 CI 1.16-3.39, p = 0.013 and ≥60 years: OR 1.86, 95% CI 1.13-3.09, p = 0.015), BMI (25-29: OR 2.87, 95% CI 1.86-4.51, p<0.001 and ≥30: OR 9.57, 95% CI 6.14-15.20, p<0.001), diabetes/hyperglycemia (OR 1.65, 95% CI 1.05-2.61, p = 0.029) and hypertriglyceridemia (OR 1.73, 95% CI 1.20-2.48, p = 0.002) were independent predictors of NAFLD. Among patients with steatosis, 22.2% (69/311) had ≥F2 fibrosis (overweight 25%, hypertriglyceridemia 32%, diabetes/hyperglycemia 34%). BMI (OR 5.22, 95% CI 2.64-11.74, p<0.001), diabetes/hyperglycemia (OR 2.12, 95% CI 1.05-4.29, p = 0.04) and hypertriglyceridemia (OR 1.94, 95% CI 1.03-3.68, p = 0.040) were independent predictors of liver fibrosis. CONCLUSIONS: This general population study from Argentina showed a high prevalence of NAFLD. Significant liver fibrosis was present in 22% of subjects with NAFLD. This information adds to the existing knowledge of NAFLD epidemiology in Latin America.

What is the optimal antimicrobial prophylaxis to prevent postoperative infectious complications after liver transplantation? A systematic review of the literature and expert panel recommendations.

BACKGROUND: Antimicrobial prophylaxis is well-accepted in the liver transplant (LT) setting. Nevertheless, optimal regimens to prevent bacterial, viral, and fungal infections are not defined. OBJECTIVES: To identify the optimal antimicrobial prophylaxis to prevent post-LT bacterial, fungal, and cytomegalovirus (CMV) infections, to improve short-term outcomes, and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. PROSPERO ID: CRD42021244976. RESULTS: Of 1853 studies screened, 34 were included for this review. Bacterial, CMV, and fungal antimicrobial prophylaxis were evaluated separately. Pneumocystis jiroveccii pneumonia (PJP) antimicrobial prophylaxis was analyzed separately from other fungal infections. Overall, eight randomized controlled trials, 21 comparative studies, and five observational noncomparative studies were included. CONCLUSIONS: Antimicrobial prophylaxis is recommended to prevent bacterial, CMV, and fungal infection to improve outcomes after LT. Universal antibiotic prophylaxis is recommended to prevent postoperative bacterial infections. The choice of antibiotics should be individualized and length of therapy should not exceed 24 hours (Quality of Evidence; Low | Grade of Recommendation; Strong). Both universal prophylaxis and preemptive therapy are strongly recommended for CMV prevention following LT. The choice of one or the other strategy will depend on individual program resources and experiences, as well as donor and recipient serostatus. (Quality of Evidence; Low | Grade of Recommendation; Strong). Antifungal prophylaxis is strongly recommended for LT recipients at high risk of developing invasive fungal infections. The drug of choice remains controversial. (Quality of Evidence; High | Grade of Recommendation; Strong). PJP prophylaxis is strongly recommended. Length of prophylaxis remains controversial. (Quality of Evidence; Very Low | Grade of Recommendation; Strong).

Twenty-year follow-up of an outbreak of hepatitis C in a small rural town of Argentina: The O'Brien Project.

INTRODUCTION AND OBJECTIVES: In 1999, a population-based survey showed a 5.6 % (102/1832) prevalence of HCV infection in O'Brien, a small rural town of Argentina. The aim of this study was to assess the impact of screening, clinical evaluation and antiviral therapy on elimination of HCV after 20 years of follow-up. PATIENTS AND METHODS: HCV+ subjects (n=102) underwent clinical, biochemical and histological evaluation to assess the presence and severity of liver disease. Antiviral therapy included pegylated interferon + ribavirin in 2005 and direct antiviral agents from 2017. RESULTS: All viremic subjects (n=84) had genotype 1b with 90%-97.5% sequence homology scores, suggesting the existence of a common source of infection (use of unsafe injections administered by the same health professional). Liver biopsy (n=55) showed chronic hepatitis in all patients. The prevalence of cirrhosis was 28% overall (29/102) and 34.5% among viremic patients. Sustained virological response (SVR) was obtained in 20/34 (59%) patients treated with interferon. From 2005 to 2017, when oral antivirals became available 37/50 untreated patients died. Median age of this group in 2005 was 67 years. Six interferon non-responders and five naive subjects received direct antiviral agents and all developed SVR. Only 1/31 patient (3.2%) with SVR died and none developed decompensated cirrhosis or HCC. In 2019, a new population-based study showed that the prevalence of HCV in O'Brien decreased 20-fold, from 5.6% to 0.28% (3/1070). CONCLUSIONS: Despite the high mortality rate precluding timely access to direct antiviral agents, the O'Brien Project is a good example of HCV micro-elimination studies.

Liver transplantation for hepatocellular carcinoma: impact of expansion criteria in a multicenter cohort study from a high waitlist mortality region.

This study aimed to compare liver transplantation (LT) outcomes and evaluate the potential rise in numbers of LT candidates with hepatocellular carcinoma (HCC) of different allocation policies in a high waitlist mortality region. Three policies were applied in two Latin American cohorts (1085 HCC transplanted patients and 917 listed patients for HCC): (i) Milan criteria with expansion according to UCSF downstaging (UCSF-DS), (ii) the AFP score, and (iii) restrictive policy or Double Eligibility Criteria (DEC; within Milan + AFP score ≤2). Increase in HCC patient numbers was evaluated in an Argentinian prospective validation set (INCUCAI; NCT03775863). Expansion criteria in policy A showed that UCSF-DS [28.4% (CI 12.8-56.2)] or "all-comers" [32.9% (CI 11.9-71.3)] had higher 5-year recurrence rates compared to Milan, with 10.9% increase in HCC patients for LT. The policy B showed lower recurrence rates for AFP scores ≤2 points, even expanding beyond Milan criteria, with a 3.3% increase. Patients within DEC had lower 5-year recurrence rates compared with those beyond DEC [13.3% (CI 10.1-17.3) vs 24.2% (CI 17.4-33.1; P = 0.0006], without significant HCC expansion. In conclusion, although the application of a stricter policy may optimize the selection process, this restrictive policy may lead to ethical concerns in organ allocation (NCT03775863).

Argentinian clinical practice guideline for surveillance, diagnosis, staging and treatment of hepatocellular carcinoma.

The A.A.E.E.H has developed this guideline for the best care of patients with hepatocellular carcinoma (HCC) from Argentina. It was done from May 2018 to March 2020. Specific clinical research questions were systematically searched. The quality of evidence and level of recommendations were organized according to GRADE. HCC surveillance is strongly recommended with abdominal ultrasound (US) every six months in the population at risk for HCC (cirrhosis, hepatitis B or hepatitis C); it is suggested to add alpha-feto protein (AFP) levels in case of inexeperienced sonographers. Imaging diagnosis in patients at risk for HCC has high specificity and tumor biopsy is not mandatory. The Barcelona Clinic Liver Cancer algorithm is strongly recommended for HCC staging and treatment-decision processes. Liver resection is strongly recommended for patients without portal hypertension and preserved liver function. Composite models are suggested for liver transplant selection criteria. Therapies for HCC with robust clinical evidence include transarterial chemoembolization (TACE) and first to second line systemic treatment options (sorafenib, lenvatinib, regorafenib, cabozantinib and ramucirumab). Immunotherapy with nivolumab and pembrolizumab has failed to show statistical benefit but the novel combination of atezolizumab plus bevacizumab has recently shown survival benefit over sorafenib in frontline.

Liver transplantation in adults with acute liver failure: Outcomes from the Argentinean Transplant Registry.

INTRODUCTION AND AIM: Liver transplantation (LT) for acute liver failure (ALF) still has a high early mortality. We aimed to evaluate changes occurring in recent years and identify risk factors for poor outcomes. MATERIAL AND METHODS: Data were retrospectively obtained from the Argentinean Transplant Registry from two time periods (1998-2005 and 2006-2016). We used survival analysis to evaluate risk of death. RESULTS: A total of 561 patients were listed for LT (69% female, mean age 39.5±16.4 years). Between early and later periods there was a reduction in wait-list mortality from 27% to 19% (p<0.02) and 1-month post-LT survival rates improved from 70% to 82% (p<0.01). Overall, 61% of the patients underwent LT and 22% died on the waiting list. Among those undergoing LT, Cox regression analysis identified prolonged cold ischemia time (HR 1.18 [1.02-1.36] and serum creatinine (HR 1.31 [1.01-1.71]) as independent risk factors of death post-LT. Etiologies of ALF were only available in the later period (N=363) with indeterminate and autoimmune hepatitis accounting for 28% and 26% of the cases, respectively. After adjusting for age, gender, private/public hospital, INR, creatinine and bilirubin, and considering LT as the competing event, indeterminate etiology was significantly associated with death (SHR 1.63 [1.06-2.51] and autoimmune hepatitis presented a trend to improved survival (SHR 0.61 [0.36-1.05]). CONCLUSIONS: Survival of patients with ALF on the waiting list and after LT has significantly improved in recent years. Indeterminate cause and autoimmune hepatitis were the most frequent etiologies of ALF in Argentina and were associated with mortality.

Simeprevir with pegylated interferon alfa 2a or 2b plus ribavirin in treatment-naive patients with chronic hepatitis C virus genotype 1 infection (QUEST-2): a randomised, double-blind, placebo-controlled phase 3 trial.

BACKGROUND: Pegylated interferon (peginterferon) alfa 2a or 2b plus ribavirin regimens were the standard of care in patients with hepatitis C virus (HCV) infection, but the sustained virological response can be suboptimum in patients with HCV genotype 1 infection. The efficacy, safety, and tolerability of the combination of simeprevir, a one-pill, once-daily, oral HCV NS3/4A protease inhibitor versus placebo, plus peginterferon alfa 2a or 2b plus ribavirin was assessed in treatment-naive patients with HCV genotype 1 infection. METHODS: In the QUEST-2, phase 3 study, done at 76 sites in 14 countries (Europe, and North and South Americas), patients with confirmed chronic HCV genotype 1 infection and no history of HCV treatment were randomly assigned with a computer-generated allocation sequence in a ratio of 2:1 and stratified by HCV genotype 1 subtype and host IL28B genotype to receive simeprevir (150 mg once daily, orally), peginterferon alfa 2a (180 µg once weekly, subcutaneous injection) or 2b (according to bodyweight; 50 µg, 80 µg, 100 µg, 120 µg, or 150 µg once weekly, subcutaneous injection), plus ribavirin (1000-1200 mg/day or 800-1400 mg/day, orally; simeprevir group) or placebo (once daily, orally), peginterferon alfa 2a or 2b, plus ribavirin (placebo group) for 12 weeks, followed by just peginterferon alfa 2a or 2b plus ribavirin. Total treatment duration was 24 weeks or 48 weeks (simeprevir group) based on criteria for response-guided therapy (ie, HCV RNA <25 IU/mL undetectable or detectable at week 4 and undetectable week 12) or 48 weeks (placebo). Patients, study personnel, and the sponsor were masked to treatment assignment. The primary efficacy endpoint was sustained virological response at 12 weeks after the planned end of treatment (SVR12). Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT01290679. Results from the primary (SVR12, week 60) analysis are presented. FINDINGS: 209 (81%) of 257 patients in the simeprevir group and 67 (50%) of 134 in the placebo group had SVR12 (adjusted difference 32·2%, 95% CI 23·3-41·2; p<0·0001). The incidences of adverse events were similar in the simeprevir and placebo groups at 12 weeks (246 [96%] vs 130 [97%]) and for the entire treatment (249 [97%] vs 132 [99%]), irrespective of the peginterferon alfa used. The most common adverse events were headache, fatigue, pyrexia, and influenza-like illness at 12 weeks (95 [37%) vs 45 [34%], 89 [35%] vs 52 [39%], 78 [30%] vs 48 [36%], and 66 [26%] vs 34 [25%], respectively) and for the entire treatment (100 [39%] vs 49 [37%], 94 [37%] vs 56 [42%], 79 [31%] vs 53 [40%], and 66 [26%] vs 35 [26%], respectively). Rash and photosensitivity frequencies were higher in the simeprevir group than in the placebo group (61 [24%] vs 15 [11%] and ten [4%] vs one [<1%], respectively). There was no difference in the prevalence of anaemia between the simeprevir and placebo groups (35 [14%] vs 21 [16%], respectively, at 12 weeks, and 53 [21%] vs 37 [28%], respectively, during the entire treatment). INTERPRETATION: Addition of simeprevir to either peginterferon alfa 2a or peginterferon alfa 2b plus ribavirin improved SVR in treatment-naive patients with HCV genotype 1 infection, without worsening the known adverse events associated with peginterferon alfa plus ribavirin. FUNDING: Janssen Infectious Diseases-Diagnostics.

Donor selection criteria for liver transplantation in Argentina: are current standards too rigorous?

Organ shortage is the major limitation for the growth of deceased donor liver transplant worldwide. One strategy to ameliorate this problem is to maximize the liver utilization rate. To assess predictors of liver utilization in Argentina. The national database was used to analyze transplant activity in 2010. Donor, recipient, and transplant variables were evaluated as predictors of graft utilization of number of rejected donor offers before grafting and with the occurrence of primary nonfunction (PNF) or early post-transplant mortality (EM). Of the 582 deceased donors, 293 (50.3%) were recovered for liver transplant. Variables associated with the nonrecovery of the liver were age ≥46 years, umbilical perimeter ≥92 cm, organ procurement outside Gran Buenos Aires, AST ≥42 U/l and ALT ≥29 U/l. The median number of rejected offers before grafting was 4, and in 71 patients (25%), there were ≥13. The only independent predictor for the occurrence of PNF (3.4%) or EM (5.2%) was the recipient's emergency status. During 2010 in Argentina, the liver was recovered in only half of donors. The low incidence of PNF and EM and the characteristics of the nonrecovered liver donors suggest that organ acceptance criteria should be less rigorous.

Results after the adoption of a MELD/PELD-based liver allocation policy in Argentina.

In July 2005, Argentina switched from a categorical liver allocation system to a MELD/PELD-based policy for patients with CLD. To analyze WL outcomes and survival after LT in children. From January 2000 to December 2010, 923 children were registered. Two consecutive five-yr periods were analyzed and compared: Era I (January 2000-July 2005) (n = 379) and Era II (July 2005-December 31, 2010) (n = 544). All data were prospectively collected and analyzed using the Kaplan-Meier method. After adopting the MELD/PELD system, WL registrations increased by 44% (from 379 to 544) and the number of LT increased by only 24% (from 278 to 365). However, three-month WL mortality rate (32% to 18%, p < 0.0001, HR 2.002 CI 95% 1.5-2.8) decreased significantly. No significant differences were observed between Era 1 and II in one-yr post-LT survival (77.5% vs. 84.1%, p = 0.3053) and in acute re-LT rate (9% vs. 5%, p = 0.1746). Under the MELD/PELD-based allocation system in Argentina, mortality on the WL significantly decreased in children with CLD without affecting post-LT survival, although reduced access to LT was observed.

Fibrosis progression in maintenance liver transplant patients with hepatitis C recurrence: a randomised study of everolimus vs. calcineurin inhibitors.

BACKGROUND & AIMS: Robust clinical data evaluating fibrosis progression in hepatitis C virus (HCV) liver transplant patients receiving an mTOR inhibitor vs. calcineurin inhibitor (CNI) are lacking. To evaluate fibrosis progression in maintenance liver transplant patients receiving everolimus- or CNI-based immunosuppression. METHODS: In a randomised, multicentre, open-label study, 43 maintenance liver transplant patients with recurrent HCV infection were randomised to continue CNI-based immunosuppression or switch to everolimus. RESULTS: For patients with biopsy data at month 12, mean Ishak-Knodell fibrosis score at baseline was 2.6 ± 0.9 (n = 14) with everolimus vs. 1.9 ± 1.1 (n = 18) with CNI (P = 0.043), and 1.9 ± 1.2 vs. 2.2 ± 1.3 at month 12. Ishak-Knodell fibrosis score decreased from baseline to month 12 by a mean of -0.7 ± 1.1 with everolimus, but increased by 0.2 ± 1.2 with CNI (P = 0.046). No acute rejection or graft losses occurred up to month 12. Estimated GFR at month 12 was 65.6 ml/min/1.73 m² with everolimus and 62.2 ml/min/1.73 m² with CNI [mean difference 3.4 ml/min/1.73 m² compared to CNI control group, 95% CI -4.9, 11.8 ml/min/1.73 m², P = 0.411 (analysis of covariance adjusting for baseline GFR)]. Adverse events occurred in 95.5% of everolimus patients and 71.4% of CNI patients (serious adverse events 31.8% and 0.0%, respectively). Adverse events led to everolimus discontinuation in five patients (22.7%). CONCLUSIONS: This exploratory study suggests that conversion from CNI to everolimus reduces progression of liver fibrosis, and preserves renal function without jeopardising efficacy in liver transplant recipients with recurrent HCV, but is associated with a higher incidence of adverse events and serious adverse events. These preliminary findings merit examination in a larger trial.

Improved waiting-list outcomes in Argentina after the adoption of a model for end-stage liver disease-based liver allocation policy.

In July 2005, Argentina became the first country after the United States to introduce the Model for End-Stage Liver Disease (MELD) for organ allocation. In this study, we investigated waiting-list (WL) outcomes (n = 3272) and post-liver transplantation (LT) survival in 2 consecutive periods of 5 years before and after the implementation of a MELD-based allocation policy. Data were obtained from the database of the national institute for organ allocation in Argentina. After the adoption of the MELD system, there were significant reductions in WL mortality [28.5% versus 21.9%, P < 0.001, hazard ratio (HR) = 1.57, 95% confidence interval (CI) = 1.37-1.81] and total dropout rates (38.6% versus 29.1%, P < 0.001, HR = 1.31, 95% CI = 1.16-1.48) despite significantly less LT accessibility (57.4% versus 50.7%, P < 0.001, HR = 1.53, 95% CI = 1.39-1.68). The annual number of deaths per 1000 patient-years at risk decreased from 273 in 2005 to 173 in 2010, and the number of LT procedures per 1000 patient-years at risk decreased from 564 to 422. MELD and Model for End-Stage Liver Disease-Sodium scores were excellent predictors of 3-month WL mortality with c statistics of 0.828 and 0.857, respectively (P < 0.001). No difference was observed in 1-year posttransplant survival between the 2 periods (81.1% versus 81.3%). Although patients with a MELD score > 30 had lower posttransplant survival, the global accuracy of the score for predicting outcomes was poor, as indicated by a c statistic of only 0.523. Patients with granted MELD exceptions (158 for hepatocellular carcinoma and 52 for other reasons) had significantly higher access to LT (80.4%) in comparison with nonexception patients with equivalent listing priority (MELD score = 18-25; 54.6%, P < 0.001, HR = 0.49, 95% CI = 0.40-0.61). In conclusion, the adoption of the MELD model in Argentina has resulted in improved liver organ allocation without compromising posttransplant survival.

Recurrent hepatitis C virus infection post liver transplantation: impact of choice of calcineurin inhibitor.

Recurrence of hepatitis C virus infection following liver transplantation (LT) for hepatitis C is universal. After LT, hepatitis C is associated with accelerated fibrosis progression and reduced graft and patient survival. Furthermore, responses to antiviral therapy in patients with recurrent hepatitis C virus post-transplant are consistently sub-optimal. Calcineurin inhibitors (CNIs) like cyclosporine A (CsA) and tacrolimus continue to dominate immunosuppressive regimens in this population; however, there is still uncertainty as to whether either offers an advantage in terms of patient outcomes. Although tacrolimus demonstrates improved efficacy in the general LT population, differences have begun to emerge between these agents regarding diabetogenic potential, antiviral activity, and fibrosis progression in patients with hepatitis C. This review critically evaluates the existing literature, providing an overview of the reported differences, concluding that despite conflicting evidence, a potential benefit of CsA in patients with hepatitis C is supported by the data and warrants further investigation. Future studies examining the role of CNIs in hepatitis C virus-positive LT recipients are required to accurately examine the effects of CNIs on outcomes such as fibrosis progression, survival, and effects on response to antiviral therapy, to provide robust information that allows clinicians to make an informed choice concerning which CNI is best for their patients.

Transcriptome at the time of hepatitis C virus recurrence may predict the severity of fibrosis progression after liver transplantation.

Allograft gene expression analysis may provide insights into the mechanisms involved in liver damage during hepatitis C virus recurrence (HCVrec) after orthotopic liver transplantation (OLT) and allow the identification of patients who have a higher risk of developing severe disease. Forty-three OLT recipients with hepatitis C virus (HCV) were evaluated. Genomewide gene expression analysis was performed with formalin-fixed, paraffin-embedded (FFPE) liver biopsy samples obtained from 21 OLT recipients with HCV at the time of clinical HCVrec, which was defined as increased alanine aminotransferase levels and detectable HCV RNA levels in serum. Patients were classified into 3 groups according to the severity of the fibrosis in the liver biopsies at 36 months post-OLT : group 1 (G1) for mild fibrosis (F0-F1), group 2 for moderate fibrosis (F2), and group 3 (G3) for severe fibrosis (F3-F4). No significant differences were observed between the groups with respect to donor age, histology during HCVrec, treated episodes of acute cellular rejection, or immunosuppression therapy. The results were validated in the remaining 22 OLT recipients with HCV using quantitative real-time polymerase chain reaction. Fifty-seven beadtypes showed significantly different expression (P < 0.001) between the groups during HCVrec. In G3, the gene expression of interleukin-28RA (IL-28RA), IL-28, and angiotensin-converting enzyme was up-regulated. Samples from G1 and G3 were used to determine whether a multigenetic classifier could be derived to predict the group class. The final model included the intercept and 9 bead types. Pairwise scatter plots of these 9 bead types revealed that G1 and G3 were well separated with respect to each gene. Our analysis has demonstrated the utility of a set of molecular markers indicating HCVrec severity early after OLT.

[Organ transplants in HIV infected patients. Update and recommendations]. / Transplante de órganos en pacientes con infeccion por el virus de la inmunodeficiencia humana. Actualizacion y recomendaciones.

Until few years ago, HIV infection was an absolute contraindication to consider organ transplants. Since HAART introduction, patient survival increased dramatically, but high mortality due to liver and kidney diseases became evident. For these reasons, this group of patients is now reconsidered for organ transplantation. In 2008, the Argentine Society of Transplants (SAT) and the Argentine Infectious Diseases Society (SADI), encouraged by the increasing published experience on kidney and liver transplants in this population, decided to form a Working Group, to prepare an update on this issue and elaborate practical recommendations for the better management of these patients. The first meeting was held on December 4th 2008. The most important conclusion was that HIV infection did not contraindicate a solid organ transplant. Later on, taking into account the accumulated experience and the available literature, the current document was prepared. HIV infected patients must fulfill certain clinical, immunological, virological and psychosocial criteria to be considered for solid organ transplants. HIV infected recipients of kidney and liver transplants currently show similar short and middle term survival to non HIV infected patients. There is not yet enough data on intrathoracic transplants in these patients in order to include them on a waiting list for these organs-transplants. Interactions between immunosupressors and antiretroviral drugs (specially protease inhibitors) are very important, and require a strict monitoring of immunosupressor levels.

Cyclosporine pharmacokinetics and blood pressure responses after conversion to once-daily dosing in maintenance liver transplant patients.

In this six-month randomized multicenter trial, we characterized cyclosporine pharmacokinetics and blood pressure profiles in maintenance liver transplant patients converting from twice-daily to once-daily cyclosporine dosing. A total of 60 patients were randomized as follows: group A (n = 14) maintained twice-daily dosing; group B (n = 24) converted to once-daily dosing at the same total daily dose as pre-conversion; and group C (n = 22) was treated the same as group B but with a 25% reduction in dose and C2 at two to three wk post-conversion. After conversion to once-daily dosing in groups B and C, trough blood levels (C0) did not change; whereas, C2 nearly doubled. The total daily area under the concentration-time curve AUC(0-24) increased by 29%. After the dose reduction in group C, the AUC(0-24) was similar to the pre-conversion value. Hence, a 25-30% dose reduction can be considered after conversion to once-daily dosing. In the study observation period in weeks 4-15, the median (25-75 percentile) C2 was 568 (469-750) ng/mL for group A; 1055 (840-1224) ng/mL for group B; and 764 (575-959) ng/mL for group C. Conversion to once-daily dosing was associated with a decrease in nighttime mean arterial blood pressure.

[Indications and timing of liver transplantation]. / Indicaciones y oportunidad del trasplante hepático.

Liver transplantation (OLT) is indicated in patients with severe and irreversible acute or chronic liver disease without alternative therapy and in the absence of contraindications. Indications for OLT can be grouped in four categories, namely cirrhosis, fulminant hepatitis, malignant hepatic tumors and liver-based genetic defects that trigger damage of other organs. Patients with cirrhosis should be referred for OLT after the onset of any of the major complications or coagulopathy. Early referral is crucial in fulminant hepatitis due to the high mortality with medical therapy and the unpredictable nature of this condition. Ideal timing for OLT is the moment in the natural history of the disease when the expected survival of patients on the waiting list is higher with than without OLT. Recent data suggest that maximal benefit of OLT is obtained in patients with a MELD score >15. However, in some cases with no imminent risk of death, OLT is indicated to improve quality of life or to prevent contraindications such as progression of hepatocellular carcinoma. At present, there is a marked disproportion between the number of donors available and the growing number of patients listed worldwide, which in turn has resulted in prolongation of the time-interval to OLT and waitlist mortality. The rationale of allocation systems utilizing the MELD score is to prioritize on the waiting list patients with severe liver dysfunction ("the sickest first") and those with hepatocellular carcinoma who may loose the benefits of OLT when waitlist time exceeds eight months.