The spectrum of hepatic functional impairment in compensated chronic hepatitis C: results from the Hepatitis C Anti-viral Long-term Treatment against Cirrhosis Trial

Within-individual reproducibility of a dual sample oral cholate challenge test (DuO) and simplified versions of the HepQuant SHUNT test

Current noninvasive liver tests measure fibrosis, inflammation, or steatosis and do not measure function. The HepQuant platform of noninvasive tests uniquely assesses both liver function and physiology through the hepatic uptake of stable isotopes of cholate. However, the prototypical HepQuant SHUNT test (SHUNT V1.0) is cumbersome to administer, requiring intravenous and oral administration of cholate and six peripheral venous blood samples over 90 min. To alleviate the burden of test administration, we explored whether an oral only (DuO) version, and other simplified versions, of the test could provide reproducible measurements of liver function. DuO requires only oral dosing and two blood samples over 60 min. The simplified SHUNT test versions were SHUNT V1.1 (oral and IV dosing but four blood samples) and SHUNT V2.0 (oral and IV dosing but only two blood samples over 60 min). In this paper, we describe the reproducibility of DuO and the simplified SHUNT tests relative to that of SHUNT V1.0; equivalency is described in a separate paper. Data from two studies comprising 236 SHUNT tests in 94 subjects were analyzed retrospectively by each method. All simplified methods were highly reproducible across test parameters with intraclass correlation coefficients >0.93 for test parameters Disease Severity Index (DSI) and Hepatic Reserve. DuO and SHUNT V2.0 improved reproducibility in measuring portal-systemic shunting (SHUNT%). These simplified tests, particularly DuO and SHUNT V2.0, are easier to administer and less invasive, thus, having the potential to be more widely accepted by care providers administering the test and by patients receiving the test.

Compartmental model describing the physiological basis for the HepQuant SHUNT test

The HepQuant SHUNT test quantifies hepatic functional impairment from the simultaneous clearance of cholate from the systemic and portal circulations for the purpose of monitoring treatment effects or for predicting risk for clinical outcome. Compartmental models are defined by distribution volumes and transfer rates between volumes to estimate parameters not defined by noncompartmental analyses. Previously, a noncompartmental analysis method, called the minimal model (MM), demonstrated reproducible and reliable measures of liver function (Translational Research 2021). The aim of this study was to compare the reproducibility and reliability of a new physiologically based compartmental model (CM) vs the MM. Data were analyzed from 16 control, 16 nonalcoholic steatohepatitis (NASH), and 16 hepatitis C virus (HCV) subjects, each with 3 replicate tests conducted on 3 separate days. The CM describes transfer of cholates between systemic, portal, and liver compartments with assumptions from measured or literature-derived values and unknown parameters estimated by nonlinear least-squares regression. The CM was compared to the MM for 6 key indices of hepatic disease in terms of intraclass correlation coefficient (ICC) with a lower acceptable limit of 0.7. The CM correlated well with the MM for disease severity index (DSI) with R² (95% confidence interval) of 0.96 (0.94-0.98, P < 0.001). Acceptable reproducibility (ICC > 0.7) was observed for 6/6 and 5/6 hepatic disease indices for CM and MM, respectively. SHUNT, a measure of the absolute bioavailability, had ICC of 0.73 (0.60-0.83, P = 0.3095) for MM and 0.84 (0.76-0.90, P = 0.0012) for CM. The CM, but not the MM, allowed determination of anatomic shunt and hepatic extraction and improved the within individual reproducibility.

The within-individual reproducibility of the disease severity index from the HepQuant SHUNT test of liver function and physiology

The HepQuant SHUNT test quantifies liver function and blood flow using systemic and portal clearances of cholate. The test can identify the risk of well-compensated patients to develop complications of cirrhosis. To confirm the reliability of a single HepQuant SHUNT test we defined its within-individual reproducibility. Healthy subjects (n = 16), 16 with nonalcoholic steatohepatitis (NASH), and 16 with chronic hepatitis C virus (HCV) underwent 3 HepQuant SHUNT tests on 3 separate days within 30 days. The test involves simultaneous administration of 20 mg 13C-cholate IV and 40 mg d4-cholate PO, and subsequent collection of 3 mL blood samples at 5, 20, 45, 60, and 90 minutes. Clearances are expressed as systemic and portal hepatic filtration rate. Portal-systemic shunting (SHUNT), a disease severity index (DSI), and an estimate of DSI (STAT) are calculated from the clearances. Reproducibility was determined by the intraclass correlation coefficient (ICC > 0.70) and Bland-Altman analysis. Equal numbers of NASH and HCV patients had either early (F0-F2) or advanced (F3/F4) stages of fibrosis. All F3/F4 subjects were clinically compensated. The intraclass correlation coefficient (ICC) for DSI was 0.94 (0.90-0.96 95% confidence interval) indicating excellent reproducibility. The other test parameters had ICCs ranging from 0.74 (SHUNT) to 0.90 (STAT). In Bland-Altman analysis, the mean of differences between measurements of DSI was 0.13 with standard deviation 2.12. The excellent reproducibility of the HepQuant SHUNT test, particularly DSI, supports the use this minimally invasive, blood-based test as a reliable test of liver function and physiology.

Performance of Acoustic Radiation Force Impulse Elastography for Staging Liver Fibrosis in Patients With Chronic Hepatitis C After Viral Eradication

BACKGROUND

Data on noninvasive liver fibrosis staging after viral eradication are unclear. This histology-based study validated the performance of liver stiffness (LS) measurements after viral eradication.

METHODS

Consecutive participants with chronic hepatitis C (CHC) who received concomitant LS measurements through acoustic radiation force impulse (ARFI) elastography and percutaneous liver biopsy were prospectively screened and analyzed.

RESULTS

Of the 644 patients, 521 (80.9%) underwent a biopsy at treatment baseline, and the remaining 123 (19.1%) underwent a biopsy at 3 years (median; interquartile range, 0.1) after the sustained virological response (SVR) to pegylated interferon-based and direct-acting antiviral treatments. The proportions of histological fibrosis stages did not differ significantly between the pretreatment and post-SVR groups (P = .0615). However, the LS values differed significantly (P < .0001). The median LS values (presented as shear wave velocities in meters per second) were 1.51 (0.92) for the pretreatment group and 1.22 (0.77) for the post-SVR group. The cutoffs (areas under the receiver operating characteristic curve, obtained using the bootstrap method) to dichotomize between METAVIR fibrosis stage F1 versus stages F2-F4, F1-F2 versus F3-F4, and F1-F3 versus F4 were 1.47 (0.8333, 95% confidence interval [CI] 0.7981-0.8663), 1.81 (0.8763, 95% CI 0.8376-0.9107), and 1.86 (0.8811, 95% CI 0.8378-0.9179) in the pretreatment group, respectively, and 1.22 (0.7872, 95% CI 0.7001-0.8624), 1.59 (0.8808, 95% CI 0.8034-0.9422), and 1.75 (0.9018, 95% CI 0.8201-0.9644) in the post-SVR group, respectively.

CONCLUSIONS

The performance of LS measurements through ARFI elastography is promising to determine the liver fibrosis stage on necroinflammation-resolved histology in CHC after viral eradication.

Long-Term Risk of Hepatocellular Carcinoma in HCV Patients Treated With Direct Acting Antiviral Agents

Sustained virologic response (SVR) after direct acting antiviral agents (DAAs) holds promise for reducing hepatocellular cancer (HCC). DAAs have recently been available long enough to estimate the long-term risk. We conducted a retrospective cohort study of hepatitis C virus (HCV) patients who achieved SVR with DAAs from 129 Veterans Health Administration hospitals between January 1, 2015, and December 31, 2015, with follow-up through September 30, 2018. We calculated the overall and quarterly HCC incidence rates. We examined the effect of demographic, clinical, and behavioral factors and the decline or increase of FIB-4 and aspartate aminotransferase to platelet ratio index (APRI) on HCC risk. Among the 18,076 patients with SVR, 544 incident cases of HCC were diagnosed during the mean 2.9 years of follow-up. The cumulative 1, 2, and 3-year risks of HCC were 1.1%, 1.9% and 2.8%, respectively. Cirrhosis was strongly associated with HCC risk (adjusted hazard ratio = 4.13, 95% confidence interval = 3.34-5.11). The quarterly incidence rate of HCC remained stable between 1.00 and 1.23/100 person-years (PY) and 1.5 to 2.3/100 PY in patients with cirrhosis. The risk of HCC was the highest in patients who had persistently high FIB-4/APRI and both with and without cirrhosis. HCC risk fell in patients with cirrhosis who experienced a decrease of FIB-4/APRI scores yet remained higher than the accepted threshold for HCC surveillance. HCC risk was also higher in patients with alcohol use, older age, and infection with HCV genotype 3. Most patients treated at an early stage of liver fibrosis had a stable low risk. Conclusion: Patients successfully treated with DAAs and at risk of HCC did not regress after 3.6 years of follow-up. HCC risk remained above the accepted thresholds for surveillance in patients with cirrhosis. These data have important implications for HCC surveillance in cured HCV patients.

Assessing hepatic impairment in Fontan-associated liver disease using the HepQuant SHUNT test

BACKGROUND & AIMS

Fontan surgery for single ventricle congenital heart disease leads to Fontan-associated liver disease (FALD). Typical laboratory tests, imaging, and histopathology cannot predict clinical severity in FALD. HepQuant SHUNT is a proprietary serum test of hepatic function and physiology that has not yet been evaluated in FALD.

METHODS

Fourteen adult FALD patients at a single urban tertiary care center who underwent a Fontan procedure in childhood received HepQuant SHUNT testing between September 2015 and April 2018. The HepQuant SHUNT disease severity index (DSI) assesses global liver function and physiology from systemic and portal hepatic filtration rates (HFRs, clearances adjusted for body mass) of orally and intravenously administered cholates labeled with deuterium or 13C. The SHUNT parameter of the test measures portal systemic shunting from the ratio of Systemic HFR to Portal HFR. Chart review included laboratory tests, imaging, and clinical findings. Data from FALD patients were compared with data from healthy controls.

RESULTS

The average DSI and SHUNT values for the FALD patients were 17.5% and 36.1%, respectively, compared to 9.2% and 24.1%, respectively, for controls. Twelve (85.7%) FALD patients had a DSI >15 (upper limit of normal). Seven (50.0%) FALD patients had SHUNT values >30% (upper limit of normal), while three FALD patients (21.4%) had SHUNT values >49%. One FALD patient with preoperative SHUNT of 69%, who underwent a combined heart-liver transplant, had confirmed cirrhotic morphology within the liver explant.

CONCLUSIONS

This pilot study demonstrated that most FALD patients had hepatic impairment detected by abnormal DSI, with a smaller number having markedly elevated SHUNT values >49% suggesting intrinsic liver disease. The HepQuant SHUNT test may be useful in detecting and quantifying liver disease severity in FALD patients.

Virologic Cure of Hepatitis C: Impact on Hepatic Fibrosis and Patient Outcomes

Treatment with direct-acting antiviral agents has revolutionized the approach to hepatitis C. We are now able to obtain high sustained virological response (SVR) rates, even in the historically difficult-to-treat patient populations. SVR translates into improved clinical outcomes, particularly overall and liver-related mortality, and benefits are more striking in patients with cirrhosis. A 2.5- to 5-fold risk reduction in the incidence of hepatocellular carcinoma and improvement in complications derived from portal hypertension have been reported as well. It is hypothesized that the benefits from SVR occur largely due to regression of fibrosis, which arises from the halt on the fibrogenic stimuli and activation of extracellular matrix reabsorption signals. Non-invasive markers of fibrosis are being utilized to assess regression, but it is still unclear how accurate they are in this clinical scenario. Interventions aiming to improve liver wellness and screening for cirrhosis-related complications should continue to be the norm after SVR.

Noninvasive assessment of liver function

PURPOSE OF REVIEW

It is our opinion that there is an unmet need in hepatology for a minimally or noninvasive test of liver function and physiology. Quantitative liver function tests define the severity and prognosis of liver disease by measuring the clearance of substrates whose uptake or metabolism is dependent upon liver perfusion or hepatocyte function. Substrates with high-affinity hepatic transporters exhibit high 'first-pass' hepatic extraction and their clearance measures hepatic perfusion. In contrast, substrates metabolized by the liver have low first-pass extraction and their clearance measures specific drug metabolizing pathways.

RECENT FINDINGS

We highlight one quantitative liver function test, the dual cholate test, and introduce the concept of a disease severity index linked to clinical outcome that quantifies the simultaneous processes of hepatocyte uptake, clearance from the systemic circulation, clearance from the portal circulation, and portal-systemic shunting.

SUMMARY

It is our opinion that dual cholate is a relevant test for defining disease severity, monitoring the natural course of disease progression, and quantifying the response to therapy.

Processes to manage analyses and publications in a phase III multicenter randomized clinical trial

Background

The timely publication of findings in peer-reviewed journals is a primary goal of clinical research. In clinical trials, the processes leading to publication can be complex from choice and prioritization of analytic topics through to journal submission and revisions. As little literature exists on the publication process for multicenter trials, we describe the development, implementation, and effectiveness of such a process in a multicenter trial.

Methods

The Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) trial included a data coordinating center (DCC) and clinical centers that recruited and followed more than 1,000 patients. Publication guidelines were approved by the steering committee, and the publications committee monitored the publication process from selection of topics to publication.

Results

A total of 73 manuscripts were published in 23 peer-reviewed journals. When manuscripts were closely tracked, the median time for analyses and drafting of manuscripts was 8 months. The median time for data analyses was 5 months and the median time for manuscript drafting was 3 months. The median time for publications committee review, submission, and journal acceptance was 7 months, and the median time from analytic start to journal acceptance was 18 months.

Conclusions

Effective publication guidelines must be comprehensive, implemented early in a trial, and require active management by study investigators. Successful collaboration, such as in the HALT-C trial, can serve as a model for others involved in multidisciplinary and multicenter research programs.

Trial registration

The HALT-C Trial was registered with clinicaltrials.gov (NCT00006164).

Functional elements associated with hepatic regeneration in living donors after right hepatic lobectomy

We quantified the rates of hepatic regeneration and functional recovery for 6 months after right hepatic lobectomy in living donors for liver transplantation. Twelve donors were studied pre-donation (baseline); 8 were retested at a mean ± SD of 11±3 days after donation (T1), 10 were retested at a mean of 91±9 days after donation (T2), and 10 were retested at a mean of 185±17 days after donation (T3). Liver and spleen volumes were measured with computed tomography (CT) and single-photon emission computed tomography (SPECT). Hepatic metabolism was assessed with caffeine and erythromycin, and hepatic blood flow (HBF) was assessed with cholates, galactose, and the perfused hepatic mass (PHM) by SPECT. The regeneration rates (mL kg(-1) of body weight day(-1)) by CT were 0.60±0.22 mL from the baseline to T1, 0.05±0.02 mL from T1 to T2, and 0.01±0.01 from T2 to T3; by SPECT they were 0.54±0.20, 0.04±0.01, and 0.01±0.02, respectively. At T3, the liver volumes were 84%±7% of the baseline according to CT and 92%±13% of the baseline according to SPECT. Changes in the hepatic metabolism did not achieve statistical significance. At T1, the unadjusted clearance ratios with respect to the baseline were 0.75±0.07 for intravenous cholate (P<0.001), 0.88±0.15 for galactose (P=0.07), 0.84±0.08 for PHM (P=0.002), and 0.83±0.19 for the estimated HBF (P=0.06). At T1, these ratios adjusted per liter of liver were up to 50% greater than the baseline values, suggesting recruitment of HBF by the regenerating liver. Increased cholate shunt, increased spleen volume, and decreased platelet count, were consistent with an altered portal circulation. In conclusion, initial hepatic regeneration is rapid, accounts for nearly two-thirds of total regeneration, and is associated with increases in HBF and cholate uptake. Right lobe donation alters the portal circulation of living donors, but the long-term clinical consequences, if there are any, are unknown.

Quantitative liver function tests improve the prediction of clinical outcomes in chronic hepatitis C: results from the Hepatitis C Antiviral Long-term Treatment Against Cirrhosis Trial

Risk for future clinical outcomes is proportional to the severity of liver disease in patients with chronic hepatitis C virus (HCV). We measured disease severity by quantitative liver function tests (QLFTs) to determine cutoffs for QLFTs that identified patients who were at low and high risk for a clinical outcome. Two hundred and twenty-seven participants in the Hepatitis C Antiviral Long-term Treatment Against Cirrhosis (HALT-C) Trial underwent baseline QLFTs and were followed for a median of 5.5 years for clinical outcomes. QLFTs were repeated in 196 patients at month 24 and in 165 patients at month 48. Caffeine elimination rate (k(elim)), antipyrine (AP) clearance (Cl), MEGX concentration, methionine breath test (MBT), galactose elimination capacity (GEC), dual cholate (CA) clearances and shunt, perfused hepatic mass (PHM), and liver and spleen volumes (by single-photon emission computed tomography) were measured. Baseline QLFTs were significantly worse (P = 0.0017 to P < 0.0001) and spleen volumes were larger (P < 0.0001) in the 54 patients who subsequently experienced clinical outcomes. QLFT cutoffs that characterized patients as "low" and "high risk" for clinical outcome yielded hazard ratios ranging from 2.21 (95% confidence interval [CI]: 1.29-3.78) for GEC to 6.52 (95% CI: 3.63-11.71) for CA clearance after oral administration (Cl(oral)). QLFTs independently predicted outcome in models with Ishak fibrosis score, platelet count, and standard laboratory tests. In serial studies, patients with high-risk results for CA Cl(oral) or PHM had a nearly 15-fold increase in risk for clinical outcome. Less than 5% of patients with "low risk" QLFTs experienced a clinical outcome.

CONCLUSION

QLFTs independently predict risk for future clinical outcomes. By improving risk assessment, QLFTs could enhance the noninvasive monitoring, counseling, and management of patients with chronic HCV.

Very low viral load (VLVL) relapse following treatment of naïve patients with chronic hepatitis C

BACKGROUND

Sustained virologic response (SVR) to treatment of naïve patients with chronic hepatitis C (HCV) with pegylated interferon and ribavirin is 50-60%. Patients who relapse have a poor response to re-treatment. We report a group of relapse patients with SVR to low-dose re-treatment after 6 months.

AIM

Characterization of HCV relapse patients with very low viral load (VLVL) (HCV RNA <5,000 IU/ml) 6 months after stopping full-dose initial treatment.

METHODS

We identified 120 consecutive naïve patients over 4 years treated with pegylated interferon alpha-2a and ribavirin with full-dose therapy for 24 weeks (non-genotype 1) or 48 weeks (genotype 1) with baseline liver biopsy and at least 6 months of follow-up after treatment. HCV RNA by PCR and hepatic blood tests were obtained monthly during treatment and at least 1, 3, and 6 months post treatment.

RESULTS

Of the initially treated patients, 54.2% had SVR, 25% non-response and 20.8% relapsed. Four of 25 who relapsed (16%) and one similar patient referred to our program had HCV RNA <5,000 IU/ml 6 months after stopping treatment (VLVL relapse). Significant differences (P < 0.05) compared with the 21 other relapse patients included all five patients who were genotype 1; 4/5 had cirrhosis, baseline HCV RNA was lower, and all had SVR to less intensive re-treatment for 6 months.

CONCLUSION

VLVL relapse patients should be sought, because SVR to re-treatment is common despite genotype 1 cirrhosis.

Treatment of chronic hepatitis C in HIV-infected patients with compensated liver cirrhosis

The greatest benefit of hepatitis C virus (HCV) therapy is seen in cirrhotics attaining sustained virological response (SVR). However, concerns about toxicity and poorer responses often discourage treatment of cirrhotics. This may be particularly relevant in HIV-HCV-coinfected patients, in whom progression of liver fibrosis is faster and treatment responses lower. This is a retrospective analysis of HIV-HCV-coinfected patients who had received peginterferon-ribavirin therapy at our institution. Individuals naïve for interferon in whom liver fibrosis had been assessed using elastometry within the year before being treated were chosen. Response rates and toxicities were compared in cirrhotics (>14.5 KPa) and noncirrhotics. Patients with previous liver decompensation were excluded. Overall, 41 cirrhotics and 190 noncirrhotics entered the study. Groups were similar in age, gender, HCV genotypes and baseline serum HCV-RNA. SVR occurred at similar rates in cirrhotic and noncirrhotics, either considered by intention-to-treat (39%vs 45%; P = 0.4) or as treated (50%vs 52%, P = 0.8). In multivariate analysis (odds ratio, 95% CI, P), SVR was associated with HCV genotypes 2-3 (5, 2.9-11, <0.01) and lower serum HCV-RNA (2, 1.4-3.03 for every log decrease, <0.01) but not with cirrhosis (1.2, 0.4-3.6, 0.6). Treatment discontinuations because of adverse events tended to be more common in cirrhotics than in noncirrhotics (17%vs 12%; P = 0.2), but only severe thrombocytopenia was more frequent in cirrhotics than in non-cirrhotics (20%vs 3% at week 24; P < 0.01). Response to peginterferon-ribavirin therapy is similar in HIV-HCV coinfected patients with and without liver cirrhosis. Therefore, treatment must be encouraged in all compensated cirrhotic patients, although closer monitoring and management of side effects, mainly thrombocytopenia, may be warranted.

Implications of opioid analgesia for medically complicated patients

Opioid analgesics have an established role in the management of postoperative pain and cancer pain, and are gaining acceptance for the management of moderate to severe chronic noncancer pain, most notably chronic low back pain and osteoarthritis, that does not respond to other interventions. Many patients with chronic pain have co-morbid medical conditions that may complicate opioid therapy. Selecting the appropriate opioid requires knowledge of how individual opioids differ with respect to metabolism and interaction with concurrent medications, as well as the reasons why specific medical conditions may influence their efficacy and tolerability. Polypharmacy is a common complicating condition in the elderly and in patients with psychiatric illness, cancer, cardiovascular disease, diabetes mellitus or other chronic illnesses. Polypharmacy, though often necessary for patients with multiple medical conditions, also multiplies the risk of drug interactions. Pharmacokinetic drug interactions can increase or reduce exposure to the opioid or concurrent medications, reducing efficacy and/or tolerability and increasing toxicity. Pharmacodynamic interactions can enhance the depressive effects of opioids, compromising safety. Patients with impaired renal or hepatic function may have difficulty clearing or metabolizing opioids and concurrent medications, leading to increased risk of adverse events. Patients with cardiovascular, cerebrovascular or respiratory disease (including smokers of >/=2 packs/day with no other diagnosis) may be more susceptible to respiratory depression, bradycardia and hypotension with any opioid, and a few specific opioids pose additional risks. Patients with cerebrovascular disease, dementia, brain injury or psychiatric illness are more susceptible to opioid effects on the CNS, which can include euphoria, cognitive impairment and sedation. Appropriate opioid selection may mitigate these effects. Even in older patients, addiction, abuse and misdirection of prescribed opioids are of concern. Higher risk exists for patients with psychiatric illness, history of substance abuse, and identifiable substance abuse risk factors. Screening for abuse potential and vigilant patient monitoring should be routine. Opioids differ in their ability to produce euphoria, based on opioid receptor agonism, but substance abusers may be more influenced by availability, familiarity and cost factors. Consequently, opioid selection has limited influence on abuse potential but can facilitate ease of monitoring. This review provides an overview of opioid use in medically complicated patients and recommendations on how to optimize analgesia while avoiding adverse events and drug interactions in the clinical setting. Articles cited in this review were identified via a search of EMBASE and PubMed. Articles selected for inclusion discussed characteristics of specific opioids and general physiological aspects of opioid therapy in important patient populations.

Quantitative tests of liver function measure hepatic improvement after sustained virological response: results from the HALT-C trial

BACKGROUND

The impact of virologic response on hepatic function has not been previously defined.

AIM

To determine the relationships of quantitative liver function tests (QLFTs) with virological responses to peginterferon (PEG) +/- ribavirin (RBV) in patients with chronic hepatitis C and to use serial QLFTs to define the spectrum of hepatic improvement after sustained virological response (SVR).

METHODS

Participants (n = 232) were enrolled in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial, had failed prior therapy, had bridging fibrosis or cirrhosis and were retreated with PEG/RBV. All 232 patients had baseline QLFTs; 24 patients with SVR and 68 nonresponders had serial QLFTs. Lidocaine, [24-(13)C]cholate, galactose and (99m)Tc-sulfur colloid were administered intravenously; [2,2,4,2-(2)H]cholate, [1-(13)C]methionine, caffeine and antipyrine were administered orally. Clearances (Cl), breath (13)CO(2), monoethylglycylxylidide (MEGX), perfused hepatic mass (PHM) and liver volume were measured.

RESULTS

Rates of SVR were 18-26% in patients with good function by QLFTs, but < or =6% in patients with poor function. Hepatic metabolism, measured by caffeine k(elim) (P = 0.02), antipyrine k(elim) (P = 0.05) and antipyrine Cl (P = 0.02) and the portal circulation, measured by cholate Cl(oral) (P = 0.0002) and cholate shunt (P = 0.0003) and PHM (P = 0.03) improved after SVR.

CONCLUSION

Hepatic dysfunction impairs the virological response to PEG/RBV. SVR improves hepatic metabolism, the portal circulation and PHM.