Jong Eun Yeon

Resistance to adefovir dipivoxil in lamivudine resistant chronic hepatitis B patients treated with adefovir dipivoxil

Background: Adefovir dipivoxil (ADV) is a potent nucleotide analogue against both the wild-type and lamivudine (LMV) resistant hepatitis B virus (HBV). The cumulative incidence of ADV resistant mutations in the nucleoside/-tide treatment naïve chronic hepatitis B patient (CHB) at weeks 48, 96, and 144 was 0, 0.8–3%, and ∼5.9%, respectively. Aims: The aim of this study was to characterise the genotypic and phenotypic mutation profiles to ADV in 67 LMV resistant CHB patients who were treated with ADV. Methods: Serum HBV DNA was quantified by real time polymerase chain reaction. The ADV mutant was detected using matrix assisted laser desorption/ionisation time of flight mass spectrometry based genotyping assays, termed restriction fragment mass polymorphism (RFMP). Results: RFMP analysis revealed that a total of 11 amino acid substitutions developed in the rt domain of the HBV polymerase in nine patients. The cumulative incidence of genotypic ADV resistance at months 12 and 24 was 6.4% and 25.4%, respectively. The rtA181V, rtN236T, and rtA181T mutations were detected in five, four, and two of the 67 patients at treatment months 12–17, 3–19, and 7–20, respectively. Serial quantification of serum HBV DNA revealed that two patients with the rtA181V mutation, with or without the rtN236T mutation, and one patient with the rtA181T mutation displayed HBV DNA rebound. Conclusion: Emergence of the ADV mutation in LMV resistant patients who are treated with ADV appeared to present earlier and more frequently than was reported in previous studies on nucleoside/-tide treatment naïve patients.

PPAR agonists treatment is effective in a nonalcoholic fatty liver disease animal model by modulating fatty-acid metabolic enzymes.

Background and Aims:  In a previous study, the authors found that reduced expression of peroxisome proliferator‐activated receptor (PPAR)‐α might play an important role in developing nonalcoholic fatty liver disease (NAFLD). The aim of this study was to analyze the effects of PPAR‐α and ‐γ agonists on NAFLD and verify the mechanisms underlying the PPAR‐α and ‐γ agonist‐induced improvements by evaluating the hepatic gene expression profile involved in fatty‐acid metabolism, using the Otsuka–Long Evans–Tokushima fatty (OLETF) rat.

Reduced expression of peroxisome proliferator-activated receptor-α may have an important role in the development of non-alcoholic fatty liver disease

Background:  Although the pathogenesis of non‐alcoholic fatty liver disease (NAFLD) remains poorly understood, metabolic syndrome associated with insulin resistance is the most reproducible factor in the development of NAFLD. Fat accumulation in hepatocytes results from an imbalance in the input, output and oxidation of fatty acid. Peroxisomes contain a battery of fatty acid oxidizing enzymes, the first of which, acyl‐CoA oxidase (AOX), initiates the β‐oxidation spiral. One of the mammalian peroxisome proliferator‐activated receptors (PPAR), PPAR‐α, regulates the transcriptional expression of the enzymes involved in fatty acid β‐oxidation. The aim of the present study was to define the role of PPAR‐α and AOX in the development of NAFLD using the Otsuka Long‐Evans Tokushima fatty (OLETF) rat model.

Insulin resistance in experimental alcohol-induced liver disease

Background and Aim:  Chronic ethanol consumption impairs liver regeneration due, in part, to inhibition of insulin signaling. This study characterizes the mechanisms and consequences of ethanol‐impaired insulin signaling in relation to oxidative injury and altered gene expression.

Fanconi's Syndrome Associated with Prolonged Adefovir Dipivoxil Therapy in a Hepatitis B Virus Patient.

Adefovir dipivoxil (ADV) is commonly used as an antiviral agent in the treatment of chronic hepatitis B or human immunodeficiency virus infection. Nephrotoxicity has been shown to occur at daily dosages of 60-120 mg. Fanconis syndrome is a generalized dysfunction of the renal proximal tubular cells, which is usually accompanied by complications. Here we report a case of Fanconis syndrome in a chronic hepatitis B patient who had been treated with a prolonged regimen of ADV at 10 mg/day. A 47-year-old man complained of severe back and chest-wall pain. He had chronic hepatitis B and had been treated with ADV at a daily dose of 10 mg for 38 months. He was hospitalized because of severe bone pain, and laboratory and radiologic findings suggested a diagnosis of Fanconis syndrome with osteomalacia. After discontinuation of the ADV, he recovered and was discharged from hospital. His laboratory findings had normalized within 2 weeks. This case indicates that Fanconis syndrome can be acquired by a chronic hepatitis B patient taking ADV at a conventional dosage of 10 mg/day. Therefore, patients treated with long-term ADV should be checked regularly for the occurrence of ADV-induced Fanconis syndrome.

Change in Serum Hepatitis B Surface Antigen Level and Its Clinical Significance in Treatment-naïve, Hepatitis B e Antigen-positive Patients Receiving Entecavir

Background/Aim We investigated changes in hepatitis B surface antigen (HBsAg) level and its correlation with clinical outcomes in treatment-naive chronic hepatitis B (CHB) patients undergoing entecavir therapy. Patients and Methods Among 51 hepatitis B e antigen (HBeAg)-positive treatment-naive CHB patients receiving entecavir for more than 1 year, 28 were enrolled. HBsAg levels were measured at baseline, 6 months, and 12 months after treatment using the Architect HBsAg QT assay (Abbott, dynamic; range: 0.05 to 125,000 IU/mL). Serum alanine aminotransferase, HBeAg, anti-HBe, and hepatitis B virus (HBV) DNA (Cobas Taqman: low detection limit 1.84 log10 copies/mL) were measured at baseline and every 3 months. The HBsAg response was defined as an HBsAg level that decreased more than 1 log10 IU/mL from baseline level at 12 months after entecavir treatment. Results Twenty-eight patients were treated for a median period of 21 months (range: 18 to 24 mo). Serum HBsAg level showed a mean of 4.0, 3.7, and 3.6 log10 IU/mL at pretreatment, 6, and 12 months, respectively, and declined significantly (P<0.001). Serum HBV DNA level showed a mean of 8.1, 3.1, and 2.4 log10 copies/mL at pretreatment, 6, and 12 months, respectively, and declined significantly (P<0.001). The decline in HBsAg level was significantly correlated with that of the HBV DNA level at 12 months from baseline (γ=0.391, P=0.044). Five patients showed an HBsAg response, and cumulative incidence of HBeAg loss at 1 year after entecavir treatment was 80% versus 30% in patients with an HBsAg response and those without, respectively (P=0.034). Conclusions Monitoring changes in quantitative HBsAg level could be a useful parameter for assessing the response to entecavir therapy in HBeAg-positive treatment-naive CHB patients.

Clinical Utility of Plasma Glypican-3 and Osteopontin as Biomarkers of Hepatocellular Carcinoma

Background/Aims α-Fetoprotein (AFP) is the biomarker most widely used to detect hepatocellular carcinoma (HCC), despite its suboptimal diagnostic accuracy. Glypican-3 (GPC3) and osteopontin (OPN) are secreted glycoproteins that are reportedly associated with tumorigenesis and metastasis. This study was conducted to evaluate the clinical utility of using plasma GPC3 and OPN as diagnostic biomarkers for HCC. Methods We measured the plasma levels of GPC3 and OPN in 120 HCC and 40 chronic liver disease (CLD) patients via an enzyme-linked immunosorbent assay. The diagnostic accuracy of each tumor marker was evaluated using receiver operating characteristic (ROC) curve analysis. Results The GPC3 levels in the HCC patients (75.8 ng/mL) were significantly higher (p=0.020) than the levels in patients with CLD (66.4 ng/mL). The area under the ROC curve (AUROC) values for GPC3 and OPN were 0.62 and 0.51, respectively. In subgroup analyses, including subgroups of HCC patients with low serum AFP and PIVKA II levels, the AUROC of GPC3 remained relatively high (0.66), and GPC3 showed a high sensitivity (62.1%) for detecting small HCC tumors. Conclusions The plasma levels of GPC3 and OPN demonstrated low diagnostic accuracy for HCC. However, GPC3 may have a complementary role in diagnosing HCC in patients with nondiagnostic levels of conventional tumor markers and with small-sized tumors.

Evolution of hepatitis B virus mutation during entecavir rescue therapy in patients with antiviral resistance to lamivudine and adefovir

BACKGROUND The efficacy of entecavir (ETV) monotherapy in treatment-experienced patients with chronic hepatitis B (CHB) is debatable. METHODS A total of 22 hepatitis B e antigen (HBeAg)-positive CHB patients who had shown viral breakthrough or suboptimal response with lamivudine (3TC) and adefovir disoproxil (ADV) therapy were treated with 1.0 mg of ETV. Clinical and virological parameters were monitored every 3 months. Restriction fragment mass polymorphism assays were used to detect antiviral resistance. RESULTS During 3TC and ADV therapy, 11 patients had rtM204V/I mutations, 2 had rtA181V/T or rtN236T, 7 had both and 2 had no 3TC- or ADV-related mutations. After switching to ETV monotherapy, the median change in serum hepatitis B virus (HBV) DNA level was -2.1 log(10) copies/ml. Virological response (HBV DNA<300 copies/ml) was achieved in 1 of 18 patients with pre-existing rt204 mutations, whereas it was achieved in all 4 patients without pre-existing rt204 mutations regardless of the presence of rt181 or rt236 mutations. Changes in mutational patterns during ETV therapy showed that rt204 mutations persisted or re-emerged. Relative abundances of rtM204V/I mutations in total viral populations gradually increased under ETV rescue, whereas those with rtA181V/T and rtN236T mutations decreased. ETV resistance mutations (rtL180M+rtT184I/L[rtS202G]+rtM204V) were detected in five patients with pre-existing rt204 mutations. CONCLUSIONS ETV monotherapy resulted in a limited virological response in patients who had previously failed 3TC and ADV rescue therapy. The limited efficacy might be associated with residual or reselected rtM204V/I mutations leading to ETV resistance. Combination treatment including potent antiviral agents should be recommended for patients with pre-existing rtM204V/I mutations.

Effects of the Temporary Placement of a Self-Expandable Metallic Stent in Benign Pyloric Stenosis

Background/Aims The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Methods Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. Results No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Conclusions Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration.

HBsAg seroclearance in chronic hepatitis b: Implications for hepatocellular carcinoma

Goals and Background The long-term clinical course, including the development of hepatocelluar carcinoma (HCC) after hepatic B surface antigen (HBsAg) seroclearance is not established. We discovered that the incidence of HCC and the risk factors for HCC in chronic hepatitis B (CHB) patients after HBsAg seroclearance. Study During 28 years, 96 CHB patients with HBsAg seroclearance were retrospectively reviewed. These patients continued to undergo HCC surveillance. The median follow-up time from initial visit was 166.5 months (range, 7 to 321 mo). Results The mean age at the initial visit and at the time of seroclearance was 39.2±10.6 years and 46.4±9.9 years, respectively. The mean age at the time of HBsAg seroclearance was significantly lower (P=0.03) in patients with spontaneous HBsAg seroclearance than patients with treatment-associated HBsAg seroclearance. During a median of 56 months (range, 7 to 238 mo) of follow-up after HBsAg seroclearance, 6 (6.5%) patients developed HCC. The mean age at the time of developing HCC was 55.8±10.3 years. On univariate analysis, the evidence of liver cirrhosis from the time of HBsAg seroclearance and age more than 45 years at the time of HBsAg seroclearance were significant risk factors for HCC development. In multivariate analysis, the evidence of liver cirrhosis at HBsAg seroclearance was the only significant risk factor for HCC development. Conclusions HCC can develop after HBsAg seroclearance in patients with known cirrhosis. Patients who achieved HBsAg seroclearance at older age (>45) may have undiagnosed cirrhosis and hence remain at risk for HCC. HCC surveillance should be carried out for both of those patient populations.