Recurrence of hepatitis C after liver transplantation (LT) is the main cause of graft loss and retransplantation. Frequent liver biopsies are essential to follow‐up hepatitis C virus (HCV)–induced liver damage. However, liver biopsy is an invasive and expensive procedure. We evaluated prospectively the diagnostic accuracy of noninvasive measurement of liver stiffness (by transient elastography) to assess the severity of hepatitis C recurrence after LT. For this purpose, we included 124 HCV‐infected liver transplant recipients who underwent 169 liver biopsies and 129 hepatic hemodynamic studies with determination of hepatic venous pressure gradient (HVPG). Simultaneously, patients underwent measurement of liver stiffness. Liver fibrosis was mild (F0‐F1) in 96 cases (57%) and significant (F2‐F4) in 73 (43%). HVPG was normal (<6 mm Hg) in 69 cases (54%) and elevated (≥6 mm Hg) in 60 (46%). Using a liver stiffness cutoff value of 8.5 kilopascals, the sensitivity, specificity, negative predictive value, and positive predictive value for diagnosis of fibrosis ≥F2 were 90%, 81%, 79%, and 92%, respectively. The area under the curve (AUC) for diagnosis of fibrosis ≥F2, ≥F3 and F4 were 0.90, 0.93, and 0.98, respectively. There was a close direct correlation between liver stiffness and HVPG (Pearson coefficient, 0.84; P < 0.001) and the AUC for diagnosis of portal hypertension (HVPG ≥6 mm Hg) was 0.93. Importantly, none of the individuals with liver stiffness below the cutoff value had either bridging fibrosis (F3) or cirrhosis (F4) or significant portal hypertension (HVPG ≥10 mm Hg). In conclusion, determination of liver stiffness is an extremely valuable tool to assess the severity of HCV recurrence after LT and in reducing the need of follow‐up liver biopsies. Liver Transpl 12:1791‐1798, 2006. © 2006 AASLD.

Background & Aims: Recurrence of hepatitis C virus (HCV) infection is a relevant problem of liver transplantation programs. We evaluated the effect of antiviral therapy on disease progression in 81 HCV-infected liver transplantation recipients. Methods: Patients with mild hepatitis C recurrence (fibrosis stage F0 to F2, n = 54) were randomized to no treatment (group A, n = 27) or peginterferon alfa-2b/ribavirin for 48 weeks (group B, n = 27). Patients with severe recurrence (F3 to F4, cholestatic hepatitis) were treated (group C, n = 27). All patients (n = 81) underwent a liver biopsy at baseline and after follow-up; paired hepatic venous pressure gradient (HVPG) measurements were available in 51 patients. Results: Thirteen (48%) patients of group B and 5 (18.5%) of group C achieved sustained virological response. Liver fibrosis progressed ≥1 stage in 40 (49%) of 81 patients: 19 (70%) of group A versus 7 (26%) of group B (P = .001) and in 14 (54%) of group C. HVPG increased (6.5 to 13 mm Hg, P < .01) in patients in whom fibrosis worsened, whereas it decreased (5 to 3.5 mm Hg, P = .017) or remained unchanged in those with fibrosis improvement or stabilization, respectively. The only variable independently associated with fibrosis improvement/stabilization was treatment (odds ratio [OR] =3.7, 95% confidence interval [CI] 1.3 to 10, P = .009). Among treated patients, alanine aminotransferase (ALT) normalization and viral clearance were independently associated with histological or hemodynamic improvement/stabilization (OR 5.3, 95% CI 1.5 to 18, P < .01; OR 7.4, 95% CI 1.4 to 38, P = .01; respectively). Conclusions: Our data demonstrate that in liver transplantation recipients, antiviral therapy slows disease progression (particularly in sustained virological responders), as shown by its effects on liver histology and on HVPG.

Liver biopsy is essential in the follow-up of HCV-infected liver transplant recipients. The aim of this study was to prospectively compare percutaneous (PLB) versus transjugular liver biopsy (TLB) in the assessment of liver damage. We also explored the diagnostic value of hepatic venous pressure gradient (HVPG) to identify patients at risk of severe HCV disease recurrence after liver transplantation (LT). One hundred sixteen paired PLB and TLB (with HVPG measurement) were performed 3 or 12 months after LT in 80 patients. Concordance for necroinflammation and fibrosis was fair or good, particularly 1 year after LT (kappa ≥ 0.6). At this point, a significant positive association was seen between the median HVPG and the fibrosis stage (2.5 mm Hg for F0; 5 mm Hg for F1, 6 mm Hg for F2, and 11.5 mm Hg for F3; Kruscal-Wallis < 0.001). Despite this strong association, portal hypertension (HVPG ≥ 6 mm Hg) was detected in 1 (5%) of 22, 4 (16%) of 25, and 6 (60%) of 10 patients with fibrosis stages 0, 1, and 2, respectively. After a median follow-up of 38 months, clinical decompensation occurred in 15 (19%) of 80 patients. Although the presence of significant fibrosis (F2-F3) 1 year after transplantation was good to predict clinical decompensation (AUC: 0.80), an HVPG of 6 mm Hg or greater was extremely accurate at identifying patients at risk of disease progression (AUC: 0.96). In conclusion , HVPG determination is a valuable tool for follow-up in patients with HCV recurrence after LT. (Hepatology 2006;43:492–499.)

Significant liver fibrosis (F ≥ 2) and portal hypertension (hepatic venous pressure gradient [HVPG] ≥ 6 mmHg) at 1 year after liver transplantation (LT) identify patients with severe hepatitis C recurrence. We evaluated whether repeated liver stiffness measurements (LSM) following LT can discriminate between slow and rapid “fibrosers” (fibrosis stage F2-F4 at 1 year after LT). Eighty-four patients who had undergone LT and who were infected with hepatitis C virus (HCV) and 19 LT controls who were not infected with HCV underwent LSM at 3, 6, 9, and 12 months after LT. All HCV-infected patients underwent liver biopsy 12 months after LT (paired HVPG measurements in 74); 31 (37%) were rapid fibrosers. Median LSM (in kilopascal) at months 6, 9, and 12 were significantly higher in rapid fibrosers (9.9, 9.5, 12.1) than in slow fibrosers (6.9, 7.5, 6.6) ( P < 0.01 all time points). The slope of liver stiffness progression (kPa × month) in rapid fibrosers (0.42) was significantly greater than in slow fibrosers (0.05) ( P < 0.001), suggesting two different speeds of liver fibrosis progression. Figures were almost identical for patients with HVPG ≥ 6 mmHg or HVPG < 6 mmHg at 1 year after LT. Multivariate analysis identified donor age, bilirubin level, and LSM as independent predictors of fibrosis progression and portal hypertension in the estimation group (n = 50) and were validated in a second group of 34 patients. The areas under the receiver operating characteristic curve that could identify rapid fibrosers and patients with portal hypertension as early as 6 months after LT were 0.83 and 0.87, respectively, in the estimation group and 0.75 and 0.80, respectively, in the validation group. Conclusion: Early and repeated LSM following hepatitis C recurrence in combination with clinical variables discriminates between rapid and slow fibrosers after LT. (Hepatology 2009.)

Glecaprevir/pibrentasvir is approved for treating adults infected with HCV genotypes 1-6. In clinical trials, glecaprevir/pibrentasvir was associated with high rates of sustained virologic response at post-treatment week 12 (SVR12) and was well tolerated. A systematic review and meta-analysis of the real-world effectiveness and safety of glecaprevir/pibrentasvir were undertaken. Real-world studies reporting SVR12 in adults with HCV infection (n ≥20) treated with glecaprevir/pibrentasvir were identified in journal publications from January 1, 2017, to February 25, 2019, and congress presentations through April 14, 2019. Random-effects meta-analysis was used to determine SVR12 rates using data from ≥2 cohorts; intention-to-treat (ITT) analyses included patients treated with glecaprevir/pibrentasvir who had SVR12 data available, discontinued early, or were lost to follow-up; modified ITT (mITT) analyses excluded those with non-virologic failure. Naïve pooling was used to calculate adverse event (AE) rates. Overall, 12,531 adults were treated with glecaprevir/pibrentasvir (18 cohorts). Of patients with post-treatment week 12 data, SVR12 rates were 96.7% (95% CI 95.4-98.1) in the ITT population (n = 8,583, 15 cohorts) and 98.1% (95% CI 97.1-99.2) in the mITT population (n = 7,001, 14 cohorts). SVR12 rates were ≥95% across subgroups (HCV genotype, cirrhosis status, treatment history, treatment duration, on-label treatment, and subgroups of interest). AEs were reported in 17.7% (1,271/7,199) of patients (8 cohorts). Serious AEs were reported in 1.0% (55/5,522) of patients (6 cohorts). The most frequent AEs were pruritus, fatigue, and headache. AE-related treatment discontinuations were reported in 0.6% (33/5,595) of patients (6 cohorts). Consistent with clinical trials, real-world evidence indicates that glecaprevir/pibrentasvir is a well-tolerated and highly effective pangenotypic treatment for a broad range of HCV-infected patients. It is important to assess treatments for hepatitis C virus (HCV) in the real world, as patient populations tend to be more diverse and potentially less adherent to treatment compared to those in clinical trials. Results from 18 studies performed in real-world clinics were pooled and analyzed to investigate the effectiveness and safety of a direct-acting antiviral combination (glecaprevir/pibrentasvir) in routine clinical practice. This analysis showed that glecaprevir/pibrentasvir is highly effective and well tolerated across all HCV genotypes and patient groups studied. It also showed that results seen in the real world are similar to the results seen in clinical trials, even in patients historically considered more challenging to treat.