High incidence of Plasmodium knowlesi malaria compared to other human malaria species in several hospitals in Malaysia

Through the regional control programme, Malaysia has been successfully reducing the incidence of Plasmodium falciparum and Plasmodium vivax infections. However, the incidence of zoonotic malaria Plasmodium knowlesi infection is increasing and now has been the major cause of malaria in Malaysia especially Malaysian Borneo. The emergence of knowlesi infection has threatened the malaria elimination programme which the government aims to reduce the overall malaria infections by 2020. Unlike other benign human Plasmodium spp., P. knowlesi can cause fatal infections. The aim of this study was to determine the incidence and distribution of five human malaria parasites including P. knowlesi in Peninsular Malaysia and Malaysian Borneo. A total of 112 blood samples were collected from seven states and district hospitals in Peninsular Malaysia and Malaysian Borneo from year 2015 to 2016. The samples were examined by microscopy and further confirmed by nested PCR assay targeting 18S rRNA gene of Plasmodium spp. Following the nested PCR assays, a total of 54 (48.2%) samples were positive for P. knowlesi infections, 12 (10.7%) cases were positive for P. vivax infections, followed by 7 (6.3%) cases of P. falciparum and 4 (3.5%) cases of P. malariae. There were 3 cases (2.7%) of mixed infections (P. knowlesi/P. vivax). However, no cases were identified as P. ovale. A total of 32 (28.6%) cases were found as negative infections. LoopMediated Isothermal Amplification Assay (LAMP) was performed to confirm inconclusive results produced by microscopy and nested PCR. P. knowlesi showed the highest prevalence in Sarawak (n= 30), Sabah (n=13), Pulau Pinang (n=5) and Pahang (n=6). PCR and LAMP was not able to detect a large number of microscopy positive samples due to DNA degradation during storage and shipping. Among all the states involved in this study, the highest prevalence of P. knowlesi infection was found in Sabah and Sarawak.

Experimental Study on Plasmodium knowlesi Normocyte Binding Protein Xa Region II (PkNBPXaII) for Erythrocyte Binding

Normocyte binding protein Xa (NBPXa) has been implied to play a significant role in parasite invasion of human erythrocytes. Previous phylogenetic studies have reported the existence of three types of NBPXa for Plasmodium knowlesi (PkNBPXa). PkNBPXa region II (PkNBPXaII) of type 1, type 2 and type 3 were expressed on mammalian cell surface and interacted with human and macaque (Macaca fascicularis) erythrocytes. The binding activities of PkNBPXaII towards human and macaque erythrocytes were evaluated using erythrocyte-binding assay (EBA). Three parameters were evaluated to achieve the optimal protein expression of PkNBPXaII and erythrocyte binding activity in EBA: types of mammalian cells, post transfection time and erythrocyte incubation time. COS-7, HEK-293, and CHO-K1 cells showed successful expression of PkNBPXaII, despite the protein expression is weak compared to the positive control. COS-7 was used in EBA. All three types of PkNBPXaII showed rosette formation with macaque erythrocytes but not with human erythrocytes. Future studies to enhance the PkNBPXaII expression on surface of mammalian cells is indeed needed in order to elucidate the specific role of PkNBPXaII in erythrocytes invasion.

Enteral myiasis causing acute dysentery: A case report

Enteral myiasis or intestinal myiasis is acquired by ingesting food or water contaminated with dipteran fly eggs or larvae. Here, we describe a patient with intestinal myiasis presenting with acute dysentery caused by the larva of Hermetia illucens. The larva was identified morphologically, and its species confirmed through molecular analysis using polymerase chain reaction and sequencing based on mitochondrial cytochrome c oxidase subunit I gene (COI).

Elimination of contamination in loop-mediated isothermal amplification assay for detection of human malaria

The LAMP assay, amplifies the target DNA rapidly, with 10-fold greater sensitivity than conventional PCR. The greater sensitivity also comes with greater risks of contamination. To overcome this issue, the current project includes either uracil DNA glycosylase (UDG) or a mineral oil overlay in the LAMP assay. Our results indicated that UDG or a mineral oil overlay can effectively prevent carryover contamination in the LAMP assay for the detection of human malaria. By incorporating these preventative methods, contamination can be eliminated and LAMP can potentially be used in the field; and point of care diagnosis for human malaria.

Stepwise self-assembly of C₆₀ mediated by atomic scale moiré magnifiers

Self-assembly of atoms or molecules on a crystal surface is considered one of the most promising methods to create molecular devices. Here we report a stepwise self-assembly of C₆₀ molecules into islands with unusual shapes and preferred sizes on a gold-indium-covered Si(111) surface. Specifically, 19-mer islands prefer a non-compact boomerang shape, whereas hexagonal 37-mer islands exhibit extraordinarily enhanced stability and abundance. The stepwise self-assembly is mediated by the moiré interference between an island with its underlying lattice, which essentially maps out the adsorption-energy landscape of a C₆₀ on different positions of the surface with a lateral magnification factor and dictates the probability for the subsequent attachment of C₆₀ to an island's periphery. Our discovery suggests a new method for exploiting the moiré interference to dynamically assist the self-assembly of particles and provides an unexplored tactic of engineering atomic scale moiré magnifiers to facilitate the growth of monodispersed mesoscopic structures.

Ribavirin enhances the action of interferon-α against hepatitis C virus by promoting the p53 activity through the ERK1/2 pathway

Background/Aims

Ribavirin significantly enhances the antiviral response of interferon-α (IFN-α) against Hepatitis C virus (HCV), but the underlying mechanisms remain poorly understood. Recently, p53 has been identified as an important factor involving the suppression of HCV replication in hepatocytes. We, therefore, decided to investigate whether and how ribavirin inhibits the replication of HCV by promoting the activity of p53.

Methods

HepG2 and HCV replicons (JFH1/HepG2) were utilized to study the relationship between ribavirin and p53. The effect of ribavirin on cell cycles was analyzed by flow cytometry. The activation of p53 and the signaling pathways were determined using immunoblotting. By knocking down ERK1/ERK2 and p53 utilizing RNA interference strategy, we further assessed the role of ERK1/2 and p53 in the suppression of HCV replication by ribavirin in a HCV replicon system.

Results

Using HepG2 and HCV replicons, we demonstrated that ribavirin caused the cell cycle arrest at G1 phase and stabilized and activated p53, which was associated with the antiviral activity of ribavirin. Compared to either ribavirin or IFN-α alone, ribavirin plus IFN-α resulted in greater p53 activation and HCV suppression. We further identified ERK1/2 that linked ribavirin signals to p53 activation. More importantly, knockdown of ERK1/2 and p53 partially mitigated the inhibitory effects of ribavirin on the HCV replication, indicating that ERK1/2-p53 pathway was involved in the anti-HCV effects of ribavirin.

Conclusion

Ribavirin stimulates ERK1/2 and subsequently promotes p53 activity which at least partly contributes to the enhanced antiviral response of IFN-α plus ribavirin against HCV.

Broken even-odd symmetry in self-selection of distances between nanoclusters due to the presence or absence of topological solitons

Depositing particles randomly on a 1D lattice is expected to result in an equal number of particle pairs separated by even or odd lattice units. Unexpectedly, the even-odd symmetry is broken in the self-selection of distances between indium magic-number clusters on a Si(100)-2×1 reconstructed surface. Cluster pairs separated by even units are less abundant because they are linked by silicon atomic chains carrying topological solitons, which induce local strain and create localized electronic states with higher energy. Our findings reveal a unique particle-particle interaction mediated by the presence or absence of topological solitons on alternate lattices.

Serum hepatitis B surface antigen concentration correlates with HBV DNA level in patients with chronic hepatitis B

BACKGROUND

Serum HBV DNA level is crucial in the management of chronic hepatitis B (CHB); however, the assay is expensive and cannot be used widely. Therefore, we explored the possibility of hepatitis B surface antigen (HBsAg) quantification as a surrogate marker for HBV DNA level in CHB patients.

METHODS

A total of 289 CHB patients were enrolled, 251 were evaluated at baseline and 75 of them were also evaluated during anti-HBV treatment. Another 38 on-treatment patients were used for validation. Serum HBsAg titre was quantified by an immunoassay and HBV DNA level by a PCR-based method. Baseline and on-treatment data were analysed.

RESULTS

In parallel to log(10) HBV DNA, the log(10) HBsAg was high in both immune tolerance and immune clearance phases, and significantly decreased in the inactive carrier state and was again increased in the reactivation phase of the CHB infection. There was a positive correlation between log(10) HBsAg and log(10) HBV DNA, which was greater in patients with chronic hepatitis, hepatitis B e antigen-positivity, greater alanine aminotransferase or HBsAg levels at baseline and during pegylated interferon treatment. Log(10) HBsAg could predict log(10) HBV DNA independently. An HBsAg titre of >900 IU/ml at baseline or >1,500 IU/ml within the first year of treatment could predict an HBV DNA level of >20,000 IU/ml, especially in subgroups of chronic hepatitis with alanine aminotransferase levels >40 IU/l. The dynamics of HBsAg might also predict serial HBV DNA changes. In the validation group, 64% of patients with on-treatment HBV DNA levels >20,000 IU/ml could be correctly predicted.

CONCLUSIONS

Serum HBsAg concentration might serve as a surrogate marker of HBV DNA level in CHB patients.

Simultaneous detection of methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa by multiplex PCR

A PCR-based assay that can simultaneously detect and differentiate five different types of nosocomial bacterial pathogens was developed. Six pairs of selected primers targeting femA (132 bp) and mecA (310 bp) of methicillin-resistant Staphylococcus aureus, gltA (722 bp) of Acinetobacter baumannii, phoA (903 bp) of Escherichia coli, mdh (364 bp) of Klebsiella pneumoniae and oprL (504 bp) of Pseudomonas aeruginosa were used in this study. The conditions were optimized for the multiplex PCR to ensure specific amplification of the selected targets. Sensitivity and specificity tests were also carried out using a blind test approach on 50 bacterial cultures and resulted in 100% for both positive and negative predictive values.

Transient elastography to assess hepatic fibrosis in hemodialysis chronic hepatitis C patients

BACKGROUND AND OBJECTIVES

Although percutaneous liver biopsy (PLB) is the gold standard for staging hepatic fibrosis in hemodialysis patients with chronic hepatitis C (CHC) before renal transplantation or antiviral therapy, concerns exist about serious postbiopsy complications. Using transient elastography (TE, Fibroscan(®)) to predict the severity of hepatic fibrosis has not been prospectively evaluated in these patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A total of 284 hemodialysis patients with CHC were enrolled. TE and aspartate aminotransferase-to-platelet ratio index (APRI) were performed before PLB. The severity of hepatic fibrosis was staged by METAVIR scores ranging from F0 to F4. Receiver operating characteristic curves were used to assess the diagnostic accuracy of TE and APRI, taking PLB as the reference standard.

RESULTS

The areas under curves of TE were higher than those of APRI in predicting patients with significant hepatic fibrosis (≥F2) (0.96 versus 0.84, P<0.001), those with advanced hepatic fibrosis (≥F3) (0.98 versus 0.93, P=0.04), and those with cirrhosis (F4) (0.99 versus 0.92, P=0.13). Choosing optimized liver stiffness measurements of 5.3, 8.3, and 9.2 kPa had high sensitivity (93-100%) and specificity (88-99%), and 87, 97, and 93% of the patients with a fibrosis stage of ≥F2, ≥F3, and F4 were correctly diagnosed without PLB, respectively.

CONCLUSIONS

TE is superior to APRI in assessing the severity of hepatic fibrosis and can substantially decrease the need of staging PLB in hemodialysis patients with CHC.

Association of IL28B gene variations with mathematical modeling of viral kinetics in chronic hepatitis C patients with IFN plus ribavirin therapy

Asian patients with chronic hepatitis C (CHC) are known to have better virological responses to pegylated (Peg) IFN-based therapy than Western patients. Although IL28B gene polymorphisms may contribute to this difference, whether favorable hepatitis C virus (HCV) kinetics during treatment plays a role remains unclear. We enrolled 145 consecutive Taiwanese patients with CHC receiving Peg-IFN α-2a plus ribavirin for the study. Blood samples were taken more frequently at defined intervals in the first 3 d. Peg-IFN was administered at week 1. It was then administered weekly in combination with daily ribavirin for 24 or 48 wk. A mathematical model fitted to the observed HCV kinetics was constructed, which could interpret the transient HCV titer elevation after Peg-IFN treatment. The results demonstrated a comparable viral clearance rate (c = 3.45 ± 3.73) (day(-1), mean ± SD) but lower daily viral production rate (P = 10(6)-10(12)) in our patients than those reported previously in Western patients. Of 110 patients with a sustained virological response (SVR), 47 (43%) had a transient elevation of viral titer within 12 h (proportion of 12 h/3 d: 44% in non-SVR vs. 70% in SVR; P = 0.029). Among 91 patients with available rs8099917 data, patients with the TT genotype had an early surge of viral titer after therapy and a higher SVR and viral clearance rate than those with the GT genotype. In conclusion, Taiwanese patients with CHC receiving Peg-IFN plus ribavirin therapy have a lower daily viral production rate than Western patients, and the rs8099917 TT genotype may contribute to the increased viral clearance rate and better virological responses in these patients.

Serum p53 gene polymorphisms and severity of hepatitis B or C-related chronic liver diseases in Taiwan

BACKGROUND AND AIMS

Polymorphisms of p53 gene are known to play an important role in hepatocarcinogenesis. We aimed to investigate the impact of p53 polymorphisms on disease progression by evaluating their prevalence among chronic hepatitis B (CHB) or hepatitis C (CHC) patients with different stages of liver disease.

METHODS

A total of 215 CHB, 108 CHC patients with different stages of liver disease and 49 healthy controls were consecutively enrolled. The codon 249 p53 mutations as well as codon 72 polymorphisms were assayed by molecular methods, and their prevalence among the enrolled subjects was evaluated.

RESULTS

All patients and controls had codon 249 wild-type sequences. Among codon 72 sequences, Pro/Pro allele frequency of Hepatitis B-related HCC (31.4%), cirrhosis (26.9%), HBV carriers (26.3%), hepatitis C-related cirrhosis (39.1%), and CHC patients (24%) were higher than that of healthy controls (18.4%). After adjustment for sex and age, codon 72 mutant and mixed type were associated with a higher likelihood of asymptomatic carrier state than those with wild type in CHB patients [odd ratio (OR): 2.53, 95% confidence interval (CI) 1.06-6.03, P = 0.037]. However, the prevalence of codon 72 mutant and mixed type were comparable with wild type among CHC patients with HCC (OR 0.70, 95% CI 0.28-1.72, P = 0.433).

CONCLUSIONS

Although serum 249(serine) p53 mutation is rarely found in Taiwanese patients, HBV carriers have a higher prevalence of codon 72 mutants than patients with much severe liver diseases or HCV infection, which implies that codon 72 mutants may affect at an earlier stage of HBV infection. Further studies are necessary to delineate the interactions of p53 mutations with HBV infection.

Pegylated interferon alfa-2a monotherapy for hemodialysis patients with acute hepatitis C

BACKGROUND

Hemodialysis patients are at risk of hepatitis C virus (HCV) infection. However, little is known about the efficacy and safety of pegylated interferon (IFN) therapy for hemodialysis patients with acute hepatitis C.

METHODS

From 2005 through 2008, 35 hemodialysis patients with acute hepatitis C who did not have spontaneous clearance of HCV by 16 weeks were treated with pegylated IFN alfa-2a at a dosage of 135 microg weekly for 24 weeks. In contrast, 7 patients with clearance of HCV by 16 weeks were under observation only. Thirty-six hemodialysis patients from 2002-2005 who had acute hepatitis C but did not receive treatment served as historical controls. The primary efficacy and safety end points were sustained virologic response (undetectable HCV RNA levels at 24 weeks after therapy) by intention-to-treat analysis and treatment-related withdrawal.

RESULTS

The rate of sustained virologic response in the treatment group was significantly higher than the rate of spontaneous HCV clearance in the control group (88.6% vs 16.7%; P < .001). Two patients (5.7%) prematurely terminated treatment at 8 and 10 weeks because of constitutional symptoms, and both did not have sustained virologic response. All but one patient had rapid virologic response (undetectable HCV RNA levels at 4 weeks of therapy), and all patients who received >12 weeks of therapy had early and end-of-treatment virologic responses. All patients who had clearance of HCV by 16 weeks had undetectable HCV RNA levels until the end of follow-up.

CONCLUSIONS

Pegylated IFN alfa-2a monotherapy is safe and efficacious for hemodialysis patients with acute hepatitis C. It is suggested that patients without spontaneous clearance of HCV by week 16 should receive therapy.

A sustained virologic response is durable in patients with chronic hepatitis C treated with peginterferon alfa-2a and ribavirin

BACKGROUND & AIMS

A sustained virologic response (SVR) to therapy for hepatitis C virus (HCV) infection is defined as the inability to detect HCV RNA 24 weeks after completion of treatment. Although small studies have reported that the SVR is durable and lasts for long periods, it has not been conclusively shown.

METHODS

The durability of treatment responses was examined in patients originally enrolled in one of 9 randomized multicenter trials (n = 1343). The study included patients who received pegylated interferon (peginterferon) alfa-2a alone (n = 166) or in combination with ribavirin (n = 1077, including 79 patients with normal alanine aminotransferase levels and 100 patients who were coinfected with human immunodeficiency virus and HCV) and whose serum samples were negative for HCV RNA (<50 IU/mL) at their final assessment. Patients were assessed annually, from the date of last treatment, for a mean of 3.9 years (range, 0.8-7.1 years).

RESULTS

Most patients (99.1%) who achieved an SVR had undetectable levels of HCV RNA in serum samples throughout the follow-up period. Serum samples from 0.9% of the patients contained HCV RNA a mean of 1.8 years (range, 1.1-2.9 years) after treatment ended. It is not clear if these patients were reinfected or experienced a relapse.

CONCLUSIONS

In a large cohort of patients monitored for the durability of an SVR, the SVR was maintained for almost 4 years after treatment with peginterferon alfa-2a alone or in combination with ribavirin. In patients with chronic hepatitis C infection, the SVR is durable and these patients should be considered as cured.

Increased incidence of gastroesophageal reflux disease in patients with chronic hepatitis B virus infection

BACKGROUND

Although chronic liver disease is associated with gastroesophageal reflux disease (GERD), the impact of chronic hepatitis B virus (HBV) infection on this association remains unclear. We thus aimed to evaluate the relationship between chronic HBV infection and GERD.

METHODS

In this prospective population-based study, 1,001 adult subjects who underwent an upper gastrointestinal endoscopic examination in a health check-up and completed a gastroesophageal reflux questionnaire were consecutively enrolled. Endoscopic findings were classified according to the Los Angeles classification. Hepatitis B surface antigen was used as a marker of HBV infection. Univariate and multivariate approaches were used to evaluate the effects of chronic HBV infection on GERD.

RESULTS

Chronic HBV infection was associated with heartburn sensation [odds ratio (OR) 1.27, 95% confidence interval 1.01-1.61, P = 0.037], and erosive esophagitis (adjusted OR 1.75, 1.03-2.97, P = 0.037). Although male gender is a risk factor of erosive esophagitis, further analyses stratified by gender and aspartate aminotransferase to platelet ratio index (APRI) showed that chronic HBV infection was associated with erosive esophagitis in female subjects (adjusted OR 2.70, 1.14-6.39, P = 0.024) and those with APRI of more than 0.3 (adjusted OR 3.94, 1.73-8.96, P = 0.001). Moreover, higher serum aspartate aminotransferase (AST) and triglyceride (TG) levels were risk factors of erosive esophagitis in patients with chronic HBV infection.

CONCLUSIONS

Our findings indicate a close association between chronic HBV infection and GERD, especially in female subjects and those with higher APRI levels. Moreover, HBV carriers with higher AST or TG levels have higher incidence of erosive esophagitis. The interactions between chronic HBV infection and GERD need further studies.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s12072-010-9184-4) contains supplementary material, which is available to authorized users.

HBsAg profiles in patients receiving peginterferon alfa-2a plus ribavirin for the treatment of dual chronic infection with hepatitis B and C viruses

BACKGROUND

With use of peginterferon alfa-2a and ribavirin combination therapy in patients with dual chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, 11.2% of patients achieved clearance of hepatitis B surface antigen (HBsAg) at 6 months after treatment; however, reactivation of HBV DNA was observed in 36.3%. We investigated the predictive potential of HBsAg quantification.

METHODS

HBsAg quantification was performed in 120 e antigen-negative patients dually infected with HBV and hepatitis C virus and treated with peginterferon alfa-2a/ribavirin for 48 weeks (HCV genotype 1; n = 74) or 24 weeks (HCV genotype 2/3; n = 46). HBsAg was quantified at baseline, week 4, week 12, end of treatment, and 24 weeks after treatment.

RESULTS

The baseline median serum HBsAg level was 120 IU/mL and decreased gradually during treatment. Low baseline HBsAg was significantly associated with HBsAg clearance (40% for HBsAg level 20 IU/mL vs 2.2% for HBsAg level >20 IU/mL; P < .05). A decrease in HBsAg level from baseline to week 12 of 50% was associated with a reduced likelihood of HBV DNA reactivation in patients with baseline undetectable serum HBV DNA (positive predictive value, 89.5%).

CONCLUSIONS

HBsAg quantification appears to be a useful indicator of posttreatment outcome in patients dually infected with HBV and hepatitis C virus.

Association of metabolic profiles with hepatic fibrosis in chronic hepatitis C patients with genotype 1 or 2 infection

BACKGROUND AND AIMS

Metabolic profiles are associated with severity of liver histology in chronic hepatitis C (CHC) infection. However, the influence of hepatitis C virus (HCV) genotypes, especially genotype 1 and 2, on the association between metabolic profiles and hepatic fibrosis remains unknown.

METHODS

We consecutively enrolled 528 CHC patients infected by HCV genotype 1 or 2, and used univariate and multivariate approaches to determine the influence of HCV genotype on the association of metabolic characteristics with severity of liver histology.

RESULTS

In univariate analysis, diabetes mellitus, obesity, higher grades of hepatic steatosis, homeostasis model assessment-insulin resistance index and alanine aminotransferase level, but lower serum total cholesterol and low-density lipoprotein level, were associated with advanced hepatic fibrosis. Advanced hepatic fibrosis was associated with an adjusted odds ratio of 13.72 (95% confidence interval, 2.15-87.7) for serum fasting blood glucose, 1.07 (1.01 to 1.13) for body mass index (BMI), and 0.03 (0.00-0.32) for total cholesterol level. Older age, lower serum total cholesterol level and more necro-inflammatory activity were associated with advanced hepatic fibrosis in both genotype 1 and 2 patients (P < 0.05). Advanced hepatic fibrosis was associated with an adjusted odds ratio of 31.18 (2.31-421.4) for fasting blood glucose level in genotype 1 infection, whereas 1.16 (1.05-1.28) for BMI in genotype 2 infection.

CONCLUSIONS

Age, serum total cholesterol, and hepatic necro-inflammation have important associations with severity of hepatic fibrosis in CHC patients. Moreover, these associations are different between HCV genotype: the effects of fasting blood glucose level and BMI are increased on genotype 1 and genotype 2 patients, respectively.

Differential effects of interferon and lamivudine on serum HBV RNA inhibition in patients with chronic hepatitis B

BACKGROUND

Lamivudine and interferon have been widely used for the treatment of patients with chronic HBV infection. Serum HBV RNA is detected during lamivudine therapy as a consequence of interrupted reverse transcription and because RNA replicative intermediates are unaffected by the drug. In this study, we aimed to determine the detectability of serum HBV RNA during sequential combination therapy of interferon and lamivudine.

METHODS

HBV DNA and RNA in serum samples were quantified by reverse transcription of HBV nucleic acid extract and real-time PCR. Samples were analysed every 2 weeks to 3 months from three groups of patients: 10 male patients treated with nucleoside analogue monotherapy for 44-48 weeks (5 with lamivudine and 5 with entecavir), 6 males on sequential interferon and lamivudine combination therapy, and 3 males on lamivudine monotherapy for 20-24 weeks.

RESULTS

HBV RNA was not detectable in any patients before treatment, but became detectable in 15 during antiviral treatment. Among the three groups, pre-treatment HBV DNA (8.1 +/-2.4 versus 7.7 +/-1.4 versus 5.1 +/-0.3 log(10) copies/ml; P=0.06), treatment and follow-up durations (45.5 +/-2.0 versus 49.7 +/-5.6 versus 48.7 +/-6.4 weeks; P=0.32) were comparable. HBV RNA was detectable at the end of treatment or follow-up in all patients with monotherapy, but in none of those with sequential combination therapy (100% versus 0%; P<0.001).

CONCLUSIONS

Compared with lamivudine therapy with detectable serum HBV RNA in patients with chronic HBV infection, interferon treatment might reduce HBV DNA replication through the inhibition of HBV RNA replicative intermediates, resulting in the loss of serum HBV RNA.

Hepatitis B virus genotype B has an earlier emergence of lamivudine resistance than genotype C

BACKGROUND

Hepatitis B virus (HBV) genotype B and C seem not to affect the therapeutic response to lamivudine (3TC). Whether a given genotype has an earlier emergence of 3TC resistance remains unclear. We thus conducted this study to elucidate the association of HBV genotype with the emergence of 3TC-resistant strains in Taiwanese patients.

METHODS

Forty chronic hepatitis B patients who developed resistance after 3TC therapy were retrospectively enrolled. HBV genotype, serum alanine aminotransferase (ALT) and HBV DNA levels were determined at baseline. The presence of 3TC-resistant mutations was confirmed by direct sequencing whenever biochemical breakthrough developed.

RESULTS

The distribution of HBV genotype B and C in 40 patients receiving 3TC therapy were 60% and 40%, respectively. The mean interval to detect 3TC-resistant strain was 19.6 +/-1.7 months. By using multivariate analysis, HBV genotype B and higher pre-treatment HBV DNA level were independently associated with earlier detection of 3TC-resistant strains. In addition, genotype B was significantly associated with development of 3TC resistance within the first 12 months of 3TC therapy compared with genotype C (odds ratio 8.27; P=0.004).

CONCLUSIONS

Compared with HBV genotype C, genotype B appears to have an earlier biochemical resistance to 3TC than genotype C. Therefore, more frequent monitoring of viral load or genotypical resistance might be needed for patients with HBV genotype B infection receiving 3TC therapy, especially during the first year.

Hepatitis B virus basal core promoter mutation and DNA load correlate with expression of hepatitis B core antigen in patients with chronic hepatitis B

BACKGROUND

Expression of intrahepatic hepatitis B core antigen (HBcAg) is related to the immunopathogenesis of hepatitis B virus (HBV) infection. This study investigated the role that HBV genotype and basal core promoter (BCP) mutation play in the expression of HBcAg.

METHODS

A total of 70 hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis (genotype B in 52 patients and genotype C in 18 patients; BCP mutation T1762/A1764 in 16 patients) were enrolled. Clinical, virologic, and histologic features were compared with regard to localization and expression of intrahepatic HBcAg. The effects that HBV genotype and BCP mutation T1762/A1764 had on expression of HBcAg were further evaluated by in vitro assays.

RESULTS

Cytoplasmic, mixed cytoplasmic/nuclear, and nuclear localization of intrahepatic HBcAg was found in 38 (56.7%), 25 (37.3%), and 4 (6.0%) patients, respectively; HBcAg was not discernible in 3 patients. A total of 58 (82.9%) of these patients expressed a high level of HBcAg. In multivariate analysis, cytoplasmic localization of HBcAg correlated only with a low HBV load in serum (P = .045) and BCP mutation (P = .04). A high expression level of HBcAg also correlated with a high HBV load in serum (P = .015) and with BCP wild-type sequence (P = .037). In vitro assays indicated that the HBV BCP mutant strain had lower subcellular expression of HBcAg than did the BCP wild-type strain.

CONCLUSIONS

HBV BCP mutation and HBV load, but not genotype, contribute to the expression of intrahepatic HBcAg.

Human leukocyte antigen-DRB1*1101 correlates with less severe hepatitis in Taiwanese male carriers of hepatitis B virus

Human leukocyte antigen (HLA) class II molecules are associated with host immune responses against hepatitis B virus infection. Male gender is the apparent host factor when someone encounters with the severity of hepatitis. The aim of this study was to investigate the association of the most polymorphic HLA class II allele, human leukocyte antigen-DRB1, with the severity of hepatitis in male carriers of hepatitis B virus. In this prospective cohort study, a total of 204 carriers of hepatitis B virus (131 men and 73 women) who have been followed-up for more than 1 year at the outpatient clinic of a university hospital were collected consecutively. Fifty carriers of hepatitis B virus (group I) with alanine aminotransferase <2x upper limit of normal (mean follow-up 83.6 months) were compared with 154 chronic hepatitis B patients (group II) with alanine aminotransferase >/=2x upper limit of normal (mean follow-up 81.3 months). Alleles of HLA-DRB1 were typed by the polymerase chain reaction-sequence specific oligonucleotide probe hybridization and genotypes of hepatitis B virus by melting curve analysis. HLA-DRB1*1101 was found in 18% of group I versus 8% of group II in male carriers (OR 0.23, P = 0.020, after adjustment for age) and 4% versus 9.4% in female carriers (P = 0.094). In male carriers harboring DRB1*1101, the distribution of hepatitis B viral genotype was comparable between the two groups. HLA-DRB1*1101 correlates with less severe hepatitis in Taiwanese male carriers of hepatitis B virus.

Association of baseline viral factors with response to lamivudine therapy in chronic hepatitis B patients with high serum alanine aminotransferase levels

Background

With the exception of alanine aminotransferase (ALT) level, baseline factors predictive of therapeutic response to lamivudine in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) remain unknown. We thus studied the influence of pre-therapy viral factors on end-of-treatment responses to lamivudine.

Methods

A total of 116 treatment-naive HBeAg-positive CHB patients who had pre-therapy ALT level >5x the upper limit of normal (ULN) and received lamivudine for 12–18 months were enrolled. HBeAg seroclearance and combined HBeAg seroclearance, ALT normalization and undetectable hepatitis B virus DNA at the end of therapy were defined as primary and secondary endpoints, respectively. Pre-therapy viral factors including viral load, genotype, precore (PC) stop codon status, basal core promoter status and pre-S deletion were determined to correlate with therapeutic endpoints.

Results

The frequency of patients with detectable PC stop codon mutation (G1896A), basal core promoter mutation (A1762T/G1764A) and pre-S deletion at baseline was 22.4%, 21.6% and 12.1%, respectively. After the end of 12–18 months of lamivudine therapy, the overall HBeAg seroclearance rate was 56.0%. Patients with HBeAg seroclearance had a higher prevalence of baseline PC stop codon mutation than those without (30.8% versus 11.8%; P=0.015). By using multivariate analyses, the odds ratio of patients with the PC stop codon mutation to develop HBeAg seroclearance was 3.33 ( P=0.024). The presence of the PC stop codon mutation also correlated with the combined response.

Conclusions

For lamivudine-treated HBeAg-positive CHB patients with pre-therapy ALT levels >5xULN, the PC stop codon mutation could predict a higher HBeAg seroclearance rate at the end of 12–18 months of therapy.

Factors affecting early viral load decline of Asian chronic hepatitis C patients receiving pegylated interferon plus ribavirin therapy

BACKGROUND

Early viral load decline following pegylated interferon-alpha2a and ribavirin therapy is an important predictor of the treatment responses in chronic hepatitis C (CHC) patients, thus, it is essential to evaluate the influence of host and viral factors on early viral load decline.

METHODS

Clinical and serial virological data were collected from 145 consecutive Asian CHC patients with pegylated interferon-alpha2a plus ribavirin therapy. A dose of pegylated interferon-alpha2a was administered at week 1 and then weekly with daily oral ribavirin for 24 or 48 weeks. Genotyping and quantification of hepatitis C virus (HCV) RNA were done using molecular methods.

RESULTS

A total of 81 patients were infected with HCV genotype 1,61 with genotype 2 and 3 with both genotypes 1 and 2. At the end of follow-up, 110 patients attained sustained virological response (SVR). In multivariate analyses, body mass index (BMI) and genotype were related to viral load decline at day 2, baseline viral load and high-density lipoprotein (HDL) cholesterol levels were correlated with viral load decline between days 2 and 28. Genotype, baseline viral load, alanine aminotransferase (ALT) levels and BMI independently predicted rapid virological response, whereas only genotype 2, lower baseline viral load and more substantial viral load decline at day 28 predicted a higher SVR.

CONCLUSIONS

HCV genotype, baseline viral load, pretreatment BMI, HDL and ALT levels have a significant effect on early viral load decline of Asian CHC patients with interferon-based therapy. Only HCV genotype, baseline viral load and viral load decline at day 28 can independently predict SVR.

Association of baseline viral factors with response to lamivudine therapy in chronic hepatitis B patients with high serum alanine aminotransferase levels

BACKGROUND

With the exception of alanine aminotransferase (ALT) level, baseline factors predictive of therapeutic response to lamivudine in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) remain unknown. We thus studied the influence of pre-therapy viral factors on end-of-treatment responses to lamivudine.

METHODS

A total of 116 treatment-naive HBeAg-positive CHB patients who had pre-therapy ALT level >5x the upper limit of normal (ULN) and received lamivudine for 12-18 months were enrolled. HBeAg seroclearance and combined HBeAg seroclearance, ALT normalization and undetectable hepatitis B virus DNA at the end of therapy were defined as primary and secondary endpoints, respectively. Pre-therapy viral factors including viral load, genotype, precore (PC) stop codon status, basal core promoter status and pre-S deletion were determined to correlate with therapeutic endpoints.

RESULTS

The frequency of patients with detectable PC stop codon mutation (G1896A), basal core promoter mutation (A1762T/G1764A) and pre-S deletion at baseline was 22.4%, 21.6% and 12.1%, respectively. After the end of 12-18 months of lamivudine therapy, the overall HBeAg seroclearance rate was 56.0%. Patients with HBeAg seroclearance had a higher prevalence of baseline PC stop codon mutation than those without (30.8% versus 11.8%; P=0.015). By using multivariate analyses, the odds ratio of patients with the PC stop codon mutation to develop HBeAg seroclearance was 3.33 (P=0.024). The presence of the PC stop codon mutation also correlated with the combined response.

CONCLUSIONS

For lamivudine-treated HBeAg-positive CHB patients with pre-therapy ALT levels >5xULN, the PC stop codon mutation could predict a higher HBeAg seroclearance rate at the end of 12-18 months of therapy.

Factors affecting early viral load decline of Asian chronic hepatitis C patients receiving pegylated interferon plus ribavirin therapy

Background

Early viral load decline following pegylated interferon-α2a and ribavirin therapy is an important predictor of the treatment responses in chronic hepatitis C (CHC) patients, thus, it is essential to evaluate the influence of host and viral factors on early viral load decline.

Methods

Clinical and serial virological data were collected from 145 consecutive Asian CHC patients with pegylated interferon-α2a plus ribavirin therapy. A dose of pegylated interferon-α2a was administered at week 1 and then weekly with daily oral ribavirin for 24 or 48 weeks. Genotyping and quantification of hepatitis C virus (HCV) RNA were done using molecular methods.

Results

A total of 81 patients were infected with HCV genotype 1, 61 with genotype 2 and 3 with both genotypes 1 and 2. At the end of follow-up, 110 patients attained sustained virological response (SVR). In multivariate analyses, body mass index (BMI) and genotype were related to viral load decline at day 2, baseline viral load and high-density lipoprotein (HDL) cholesterol levels were correlated with viral load decline between days 2 and 28. Genotype, baseline viral load, alanine aminotransferase (ALT) levels and BMI independently predicted rapid virological response, whereas only genotype 2, lower baseline viral load and more substantial viral load decline at day 28 predicted a higher SVR.

Conclusions

HCV genotype, baseline viral load, pretreatment BMI, HDL and ALT levels have a significant effect on early viral load decline of Asian CHC patients with interferon-based therapy. Only HCV genotype, baseline viral load and viral load decline at day 28 can independently predict SVR.

The non-structural 5A protein of hepatitis C virus exhibits genotypic differences in interferon antagonism

BACKGROUND/AIMS

Patients infected with hepatitis C virus (HCV) genotype 2 or 3 usually respond better to interferon (IFN) treatment than those infected with genotype 1. In this study, we investigated whether the non-structural 5A protein (NS5A) of HCV genotypes 1 and 2 (1b-NS5A and 2a-NS5A, respectively) exerted differential counteractivities against IFN treatment.

METHODS

We compared the inhibitory effects of 1b-NS5As and 2a-NS5As on IFN activity. We also investigated the replication inhibition of HCV subgenomic replicons containing 1b-NS5A or 2a-NS5A in response to IFN treatment.

RESULTS

1b-NS5As exerted more profound inhibitory effects on IFN activity than 2a-NS5As. The replication of the 2a-NS5A-containing replicons was more sensitive to IFN treatment than that of the 1b-NS5A-containing replicons. Deletion of the interferon sensitivity-determining region/protein kinase R-binding domain (PKR-BD), the V3 domain, or the C-terminus region of NS5A significantly abrogated its anti-IFN activity. Domain swapping between 1b-NS5A and 2a-NS5A in the V3 domain and/or the C-terminus region resulted in a transfer of their anti-IFN activity.

CONCLUSIONS

1b-NS5As exert higher magnitudes of IFN antagonism than do 2a-NS5As. The V3 and the C-terminus regions are responsible for the differential anti-IFN effects. This phenomenon may partly explain the genotype-linked differences in the response of HCV to IFN treatment.

Pegylated interferon-alpha-2a plus ribavirin for treatment-naive Asian patients with hepatitis C virus genotype 1 infection: a multicenter, randomized controlled trial

BACKGROUND

Comparable sustained virologic response (SVR) rates have been documented between Asian patients who received 24 weeks of pegylated interferon (IFN) plus ribavirin and white patients who received 48 weeks of combination therapy for hepatitis C virus genotype 1 (HCV-1) infection. Whether a 48-week course of combination therapy shows a better SVR rate than a 24-week course of such therapy among Asian patients with HCV-1 infection has not been confirmed in multicenter, randomized studies.

METHODS

In this multicenter, randomized trial, 308 treatment-naive HCV-1-infected Asian patients were randomly assigned to receive either 24 or 48 weeks of pegylated IFN-alpha-2a (180 microg per week) plus ribavirin (1000-1200 mg/day) therapy. The primary end point was SVR, defined as an undetectable serum HCV RNA level 24 weeks after discontinuation of therapy. In addition, rapid virologic response (RVR) was defined as an undetectable serum HCV RNA level at week 4 of therapy, and complete early virologic response was defined as an undetectable serum HCV RNA level at 12 weeks of therapy in the absence of RVR.

RESULTS

By intention-to-treat analysis, patients who received 48 weeks of therapy had a significantly higher SVR rate than did those who received 24 weeks of therapy (76% vs. 56%; P < .001). Among patients with a baseline serum HCV RNA level <800,000 IU/mL and RVR, SVR rates were comparable between 24- and 48-week courses of therapy (94% vs. 100%; P = .13). In contrast, 48 weeks of therapy was associated with a significantly higher SVR rate than was 24 weeks of therapy among patients without RVR (39% vs.16%; P = .01) and among those who achieved a complete early virologic response (44% vs. 20%; P = .02).

CONCLUSIONS

In treatment-naive Asian patients with HCV-1 infection, 48 weeks of pegylated IFN-alpha-2a plus ribavirin therapy is associated with a higher SVR rate, compared with 24 weeks of such therapy. Patients with a baseline serum HCV RNA level <800,000 IU/mL and who have achieved an RVR can receive a 24-week course of therapy without compromising the SVR rates; however, those who have not achieved an RVR but who have achieved a complete early virologic response should receive a 48-week course of therapy.

A higher alanine aminotransferase level correlates with earlier hepatitis B e antigen seroconversion in lamivudine-treated chronic hepatitis B patients

BACKGROUND/AIMS

A pretherapy serum alanine aminotransferase (ALT) level above five times the upper limit of normal (ULN) is known to predict hepatitis B e antigen (HBeAg) seroconversion during lamivudine therapy for chronic hepatitis B patients. However, whether an even higher pretherapy serum ALT value or other viral factors could affect treatment responses remains unclear.

PATIENTS AND METHODS

A total of 253 HBeAg-positive chronic hepatitis B patients who had a pretherapy serum ALT level over five times ULN and received lamivudine for 12-18 months were retrospectively collected. Among these patients, 38% had received prior lamivudine treatment. HBeAg seroconversion was the primary endpoint of treatment. Baseline clinical and viral features were compared between responders and non-responders at the end of treatment and 6 months post-treatment.

RESULTS

At the end of therapy, the overall HBeAg seroconversion rate was 33.6%. For lamivudine-naïve patients, the HBeAg seroconversion rate was 37.8%. Subgroup analysis showed that patients with pretherapy ALT levels over 10 times ULN had a significantly higher HBeAg seroconversion rate than those with a pretherapy ALT level between five and 10 times ULN at 3 months (P=0.045) and 6 months (P=0.037) of lamivudine treatment. No significant difference was found in terms of pretherapy serum ALT values, viral load and genotypes between seroconverters and non-seroconverters.

CONCLUSIONS

For lamivudine-treated HBeAg-positive patients with pretherapy ALT levels over five times ULN, an even higher ALT level could predict earlier HBeAg seroconversion; however, neither ALT levels nor viral factors correlate with higher response rates after 12-18 months of treatment.

Esophageal varices: noninvasive diagnosis with duplex Doppler US in patients with compensated cirrhosis

PURPOSE

To prospectively develop and evaluate the accuracy of a duplex Doppler ultrasonographic (US) index for predicting the presence or absence of esophageal varices in patients with compensated cirrhosis (Child-Pugh class A) by using endoscopy as the reference standard.

MATERIALS AND METHODS

The study had institutional review board approval; all participants gave informed consent. Data in a total of 383 prospectively enrolled patients who underwent duplex Doppler US and screening endoscopy were divided into training (n = 240) and validation (n = 143) sets. Duplex Doppler US indexes, including mean portal vein velocity (PVV), hepatic impedance indexes, splenic impedance indexes, and the splenic index were evaluated with univariate and multivariate logistic regression analyses to find the independent factors predictive of the presence of esophageal varices. Receiver operating characteristic (ROC) curves were constructed for these factors to evaluate diagnostic accuracy in the training set and reproducibility in the validation set.

RESULTS

Multivariate logistic regression analysis showed that splenic index and mean PVV were predictive of the presence of esophageal varices in the training set. A splenoportal index (SPI) was calculated as the splenic index divided by mean PVV to amplify the opposite effects on esophageal varices. Areas under ROC curves for SPI were significantly higher than those for the splenic index (0.93 vs 0.90, P = .02) and mean PVV (0.93 vs 0.67, P < .001) in the training set and in the validation set (0.96 vs 0.91 for splenic index, P = .01; 0.93 vs 0.80 for mean PVV, P < .001). An SPI threshold of 3.0 had 92% sensitivity, 93% specificity, 91% positive predictive value, and 94% negative predictive value for esophageal varices. Applying this cutoff value correctly predicted the presence or absence of esophageal varices in 92% of the patients without screening endoscopy.

CONCLUSION

SPI can serve as a useful noninvasive index to predict the presence or absence of esophageal varices.

Hepatitis B viral genotype in Taiwanese patients with acute hepatitis B

BACKGROUND/AIMS

The correlation of HBV genotype with clinical outcome has been recognized in chronic hepatitis B patients. However, there are few reports on the distribution and clinical significance of HBV genotypes in acute hepatitis B patients.

METHODOLOGY

Nineteen acute hepatitis B patients were identified and their HBV genotypes were determined. The serological and clinical data were thus compared between patients with different HBV genotypes.

RESULTS

Two HBV genotypes (B and C) were found in the patients. Genotype B was more predominant than genotype C (12 vs. 7). The age, serum alanine aminotransferase level, serum alpha-fetoprotein level, and serum HBV DNA level were not significantly different between patients infected with genotype B or C. None of them had persistent HBsAg for longer than 6 months.

CONCLUSIONS

Genotype B predominates in acute hepatitis B patients in Taiwan; however, the clinical features between genotype B and genotype C patients are comparable.

HBeAg-negative chronic hepatitis B: cost-effectiveness of peginterferon alfa-2a compared to lamivudine in Taiwan

OBJECTIVE

In Taiwan, the carrier rate of hepatitis B surface antigen is 15% to 20%, one of the highest in the world. Among chronic hepatitis B (CHB) patients, hepatitis B e antigen (HBeAg)-negative accounts for approximately 40% to 50% of these patients. A recent study found that peginterferon alfa-2a (40 KD) is more effective than lamivudine in treating HBeAg-negative CHB, but its cost-effectiveness has not been evaluated. Our objective is to evaluate the incremental cost-effectiveness of 48 weeks of peginterferon alfa-2a compared to 48 weeks of lamivudine, from the perspective of the Taiwan Bureau of National Health Insurance.

METHODS

A Markov model was used to simulate the natural history of HBeAg-negative CHB in a cohort of 40-year-old patients. Efficacy, disease progression, economic, and quality-of-life data were derived from published literature and a survey of clinical experts in Taiwan. Life expectancy, quality-adjusted life expectancy, lifetime costs in New Taiwan Dollars (NTD) (1 USD = 31.96 NTD), and incremental cost-effectiveness ratios (ICERs) were calculated.

RESULTS

The gain in quality-adjusted life-years (QALYs) for 48 weeks of peginterferon alfa-2a compared to 48 weeks of lamivudine was 0.45 at an additional cost of 157,000 NTD (4900 USD), resulting in an ICER of 347,000 NTD (10,900 USD) per QALY gained. The 95% central range for the ICER from a probabilistic sensitivity analysis was 228,000-566,000 NTD (7100-17,700 USD).

CONCLUSIONS

In HBeAg-negative CHB, 48 weeks of treatment with peginterferon alfa-2a compared to 48 weeks of lamivudine appears to offer life expectancy and quality-of-life improvements at an acceptable cost-effectiveness ratio.

Metabolic profiles in patients with chronic hepatitis C: a case-control study

BACKGROUND

The clinical implications of metabolic profiles in patients with chronic hepatitis C remain controversial. To study the association of metabolic abnormalities with chronic hepatitis C, we conducted a case-control study with special emphasis on serum lipid pattern, fasting blood glucose, and adiponectin.

METHODS

We enrolled 500 patients with chronic hepatitis C and 536 sex and age-matched controls. Unadjusted and adjusted associations of demographic and metabolic variables were estimated.

RESULTS

Chronic hepatitis C patients had higher alanine aminotransferase (ALT) and high-density lipoprotein-cholesterol levels, but lower total cholesterol (TC), triglyceride (TG), and low-density lipoprotein-cholesterol levels than controls. Stratifying ALT level according to its upper limit of normal, HCV infection was associated with younger age, female gender, and higher TC levels in chronic hepatitis C patients with normal ALT levels, but with lower TC and lower TG levels in those with abnormal ALT levels. By using multiple linear regression analyses for subjects with available adiponectin data, presence of HCV infection was independently associated with higher serum adiponectin levels.

CONCLUSIONS

Metabolic profiles of chronic hepatitis C patients are affected by age, gender, serum adiponectin, and ALT levels. Further longitudinal studies are needed to clarify the complex interplay between HCV infection and metabolic profiles.

High hepatitis C viral load is associated with insulin resistance in patients with chronic hepatitis C

BACKGROUND AND AIMS

Although insulin resistance affects liver fibrosis progression and treatment response in chronic hepatitis C (CHC), the relationship between chronic hepatitis C virus (HCV) infection and insulin resistance (IR) remains to be firmly established. We thus studied the impact of host, metabolic and viral factors on IR in CHC patients.

METHODS

A total of 162 CHC patients with complete clinical data were enrolled. Among them, 94 received histological examinations. Quantitative HCV RNA was assayed by a real-time polymerase chain reaction (PCR) assay. Genotyping was performed by reverse transcription PCR with type-specific primers. The pretreatment IR index was determined using homeostasis model assessment (HOMA), and an index value of more than 2.4 was designated IR. Unadjusted and adjusted association of the HCV RNA level and IR was further analysed.

RESULTS

In multivariate linear regression analysis, a dose-response relationship was observed between the log(10) HCV RNA level and the presence of IR. IR was positively correlated with body mass index, triglyceride, HCV RNA and alanine aminotransferase levels, but negatively correlated with adiponectin level. Subgroup analysis stratified by HCV genotype showed that there was a trend towards a higher HOMR-IR index value and lower adiponectin levels in genotype 1 patients. Histological analysis showed that IR was positively associated with the severity of hepatic steatosis.

CONCLUSIONS

Our data indicate that higher HCV RNA levels are associated with the presence of IR in CHC patients. Further studies are needed to clarify the interplays between HCV infection, IR and adiponectin in an attempt to develop new adjuvant therapy for CHC.

Noninvasive diagnosis of hepatic fibrosis in patients with chronic hepatitis C by splenic Doppler impedance index

BACKGROUND & AIMS

The value of Doppler ultrasonography to evaluate the severity of hepatic fibrosis in patients with chronic hepatitis C (CHC) remains controversial.

METHODS

Consecutive histologically proven patients with CHC over a 4-year period were divided into training (n = 335) and validation (n = 168) sets. Hepatic Doppler impedance index, splenic Doppler impedance index, and mean portal vein velocity were evaluated for all patients before liver biopsies. Multivariate logistic regression was performed to find the independent factors to predict patients with significant fibrosis (>/=F2) and cirrhosis (F4) in the training set. Receiver operating characteristic curves were constructed for these factors to evaluate the diagnostic accuracy of significant hepatic fibrosis and cirrhosis in the training set, and in the validation set to evaluate the reproducibility.

RESULTS

Multivariate logistic regression revealed that the splenic arterial pulsatility index (SAPI) and the mean portal vein velocity were predictive of significant fibrosis (>/=F2) and cirrhosis (F4). Receiver operating characteristic analysis showed the areas under the curves of regression models and SAPI were comparable in predicting significant fibrosis (0.88 vs 0.87, P = .22) and cirrhosis (0.92 vs 0.90, P = .12) in the training set. Areas under the curves of SAPI were 0.89 and 0.92 in predicting significant hepatic fibrosis and cirrhosis in the validation set. By choosing optimized cut-off levels, 54% and 76% of the patients with significant hepatic fibrosis and cirrhosis could be predicted correctly.

CONCLUSIONS

SAPI is accurate and reproducible for assessing the severity of hepatic fibrosis in patients with CHC. Applying this simple Doppler index can decrease the need for staging liver biopsy.

Subgenotypes of hepatitis B virus genotype C do not correlate with disease progression of chronic hepatitis B in Taiwan

BACKGROUND

Hepatitis B virus (HBV) genotype C (HBV/C) has two subgenotypes: HBV/Cs and Ce. The prevalence and clinical implications of subgenotype Cs and Ce in Taiwanese HBV carriers remain unknown.

METHODS

Subgenotypes of HBV/C were determined in 242 Taiwanese HBV carriers with various stages of liver disease. The clinical as well as virologic features between patients with HBV/Cs and HBV/Ce infection were further compared.

RESULTS

HBV/Ce was the predominant subgenotype in Taiwan. The prevalence of HBV/Ce was 93.6% in the inactive carriers group, 84.2% in chronic hepatitis patients, 81.2% in cirrhosis patients, 92.5% in hepatocellular carcinoma (HCC) patients without cirrhosis and 91.9% in HCC patients with cirrhosis. There was no significant difference in the distribution of the HBV/C subgenotypes among patients with different stages of liver disease.

CONCLUSIONS

Subgenotypes of HBV/C may not have a clinical impact on the disease progression of chronic hepatitis B in Taiwan.

Ribavirin up-regulates the activity of double-stranded RNA-activated protein kinase and enhances the action of interferon-alpha against hepatitis C virus

BACKGROUND

Ribavirin's mechanism of action in the treatment of chronic hepatitis C remains to be clarified. Double-stranded RNA-activated protein kinase (PKR) plays a role in cell defense against virus infection. This study investigated whether PKR is a mediator of the effectiveness of ribavirin, used either alone or in combination with interferon (IFN)- alpha , against hepatitis C virus (HCV) infection.

METHODS

Primary human hepatocytes and HCV-replicon cells were treated with ribavirin and/or IFN- alpha . PKR activity was assayed by immunoblotting. A pulse-chase assay of the half-life of PKR protein was performed to study whether ribavirin decreases PKR degradation. We used small-interference RNA (siRNA) to knock down PKR to assess its importance in the suppression of HCV-RNA replication in the replicon system.

RESULTS

Ribavirin was able to up-regulate the levels of phosphorylated PKR and phosphorylated eIF2 alpha , leading to suppression of HCV-RNA replication. The effects that treatment with ribavirin plus IFN- alpha had on PKR activity were greater than those observed for treatment with either ribavirin alone or IFN- alpha alone. Knockdown of PKR increased HCV-RNA replication, supporting the importance of PKR in the control of HCV-RNA replication. The pulse-chase experiment showed that ribavirin can reduce the degradation rate of PKR protein.

CONCLUSION

These results suggest that the anti-HCV action of ribavirin is partly attributable to its ability to up-regulate PKR activity.

Early Viral Kinetics during Treatment of Chronic Hepatitis C Virus Infection with Pegylated Interferon Alpha plus Ribavirin in Taiwan

OBJECTIVES

Early hepatitis C viral (HCV) kinetics following pegylated interferon-alpha (PEG-IFN) and ribavirin help to assess treatment in the Western world. Whether this functions in Taiwanese patients remains unknown. Studying the early HCV kinetics in Taiwanese patients may clarify this issue.

METHODS

Six chronic hepatitis C patients were enrolled. A PEG-IFN-alpha dose was administered at week 1, then it was administered weekly with daily ribavirin for 24 weeks. Serum HCV RNA levels were determined frequently during the trial and qualitatively at week 49. Kinetic parameters epsilon (effectiveness at inhibiting viral production)and delta (loss rate of infected cells) were estimated from viral loads and alanine aminotransferase (ALT) kinetics, respectively.

RESULTS

All serum HCV RNA levels became undetectable at week 12. The epsilon ranged from 0.4128 to 0.9904 and delta from 0.0019 to 0.1245. The log values of viral load differences between day 7 and 14 ranged from 0.15 to 1.21. Only 1 patient had an abnormal ALT level at week 49.

CONCLUSIONS

Viral kinetic parameters in Taiwanese patients were similar to those in Western studies. However, the early viral decline pattern and viral negativity rate in Taiwanese patients might be different from Caucasian patients. Further large-scale studies to clarify this issue are ongoing.

Association of pre-S deletion mutant of hepatitis B virus with risk of hepatocellular carcinoma

BACKGROUND

Pre-S deletion mutant of hepatitis B virus (HBV) affects the expression of middle and small surface proteins, resulting in intracellular accumulation of large surface protein. The correlation between pre-S deletion mutant and risk of hepatocellular carcinoma (HCC) in hepatitis B virus carriers remains unclear.

METHODS

Using molecular assays, pre-S deletion mutant of HBV were determined in 266 patients with chronic HBV genotype B or C infection. They included 202 asymptomatic carriers and 64 HCC patients.

RESULTS

The overall prevalence of pre-S deletion mutant was 16.5%. Hepatocellular carcinoma (odds ratio [OR], 3.23; 95% confidence interval [CI], 1.23-8.48, P = 0.02) and genotype C (OR, 3.19; 95%CI, 1.54-6.62, P = 0.002) were independently associated with the presence of pre-S deletion mutant. The prevalence of pre-S deletion mutant was comparable between HCC patients with genotype B and C infection. Nevertheless, in asymptomatic carriers, patients with genotype C infection were significantly associated with the presence of pre-S deletion mutant compared to those with genotype B infection (20.8% vs 7.2%, P = 0.007). Compared with age- and genotype B-matched asymptomatic carriers, young HCC patients (<50 years of age) had a significantly higher frequency of pre-S deletion (3.4% vs 20%, P = 0.04).

CONCLUSIONS

Pre-S deletion mutant is more frequent in HBV carriers with genotype C infection, and those with pre-S deletion mutant may be associated with the development of HCC, irrespective of HBV genotype.

Hepatitis B viral factors in HBeAg-negative carriers with persistently normal serum alanine aminotransferase levels

Chronic hepatitis B patients with high-normal serum ALT (levels of 0.5-1x upper limit of normal) are still at risk of liver disease progression. We thus investigated the correlation between serum ALT level and hepatitis B viral factors in HBeAg-negative carriers with persistently normal serum ALT level (PNALT). Baseline clinical and virological features of 414 HBeAg-negative carriers, including 176 (42.5%) with low-normal ALT (levels of less than 0.5x upper limit of normal) and 238 (57.5%) with high-normal ALT, were compared. Compared with HBV carriers with low-normal ALT, those with high-normal ALT were older (41 vs. 37 years, P<0.001) and had a greater frequency of serum HBV DNA level>10(4) copies/ml (63.4% vs. 47.5%, P<0.001) as well as a higher prevalence of basal core promoter T1762/A1764 mutant (36.5% vs. 24.2%, P=0.01). Multivariate analysis showed that factors associated with a high-normal serum ALT level included male sex [odds ratio (OR), 1.82; 95% confidence interval (CI), 1.10-3.01, P=0.019], increasing age (OR, <30 years: 1, reference; 30-39 years: 2.43, 95% CI, 1.18-5.03, P=0.016; 40-49 years: 4.22, 95% CI, 1.99-8.93, P<0.001; >or=50 years: 4.06, 95% CI, 1.69-9.78, P=0.002) and serum HBV DNA level>10(4) copies/ml (OR, 1.83; 95% CI, 1.07-3.13, P=0.027).

CONCLUSION

HBeAg-negative patients with persistently normal ALT are not a homogenous group, and those with high-normal ALT share some of the characteristics that have been associated with adverse long-term outcomes.

Dynamics of hepatitis B e antigen index ratio correlate with treatment response in chronic hepatitis B patients

BACKGROUND/AIM

Hepatitis B e antigen (HBeAg) seroconversion is an important event in the natural history of chronic hepatitis B virus (HBV) infection. Whether early dynamics of HBeAg index ratio could predict therapeutic endpoint of HBeAg seroconversion in patients receiving lamivudine remains unclear and thus deserves investigation.

METHODS

A total of 52 patients (males/females, 40/12; mean age, 31.1+/-7.5 years) with HBeAg-positive chronic hepatitis B and serum alanine aminotransferase (ALT) level > or = 5 x upper limit of normal were enrolled. They received daily 100 mg lamivudine for at least 1 year. Pretreatment HBeAg index ratio and the dynamics during treatment [early serologic response (ESR) and serologic breakthrough (SB)] between responders and non-responders were compared.

RESULTS

Of these 52 patients, mean pretreatment serum ALT level was 580 IU/l and baseline HBeAg index ratio (S/N) was 37.9. The overall 1-year on-treatment combined response rate was 50%. By using linear regression analysis, HBeAg index ratio was positively correlated with serum HBV DNA level (Pearson's correlation coefficient: 0.62, P<0.0001). By using multivariate logistic regression analysis, ESR could predict the success of treatment response (P=0.0302), and SB had a 90% positive predictive value of treatment failure.

CONCLUSIONS

HBeAg index ratio is closely correlated with serum HBV DNA level, and the dynamics of HBeAg index ratio may predict 1-year on-treatment combined response to lamivudine in HBeAg-positive chronic hepatitis B patients.

Discontinuation of lamivudine treatment for hepatitis flare after kidney or heart transplantation in hepatitis B surface antigen-positive patients: A retrospective case series

BACKGROUND

Limited data are available on the clinical course of hepatitis B virus (HBV) infection after discontinuation of lamivudine prescribed for kidney or heart posttransplantation hepatitis flare

OBJECTIVE

The purpose of this study was to investigate the reasons for discontinuation, subsequent reappearance of HBV DNA, and mortality in heart and kidney transplant recipients who discontinued lamivudine treatment.

METHODS

This retrospective case series followed up male and female hepatitis B surface antigen (HBsAg)-positive Taiwanese transplant recipients from the National Taiwan University Hospital, Taipei, Taiwan, between July 1989 and January 1999. Biochemical, virologic, and serologic parameters and liver-related mortality of patients who discontinued lamivudine 100 mg QD prescribed for posttransplantation hepatitis flare were compared with those in a group of patients who continued use of lamivudine administered for the same indication over the same period of time. Serum HBV DNA levels were checked in all patients before and after discontinuation of lamivudine, and after resumption of lamivudine treatment and in patients with breakthrough hepatitis flare.

RESULTS

A total of 39 HBsAg-positive transplant recipients (mean [SD] age, 45 [10.0] years) were identified during regular follow-up visits. Nine patients discontinued lamivudine use; 11 patients who continued it were selected as a control group. No significant between-group differences were observed in mean (SD) age (46 [14.0] vs 45 [6.9] years), sex (men/women,vs 1), type of transplant received (heart/kidney,vs ), or pretransplantation liver function test results. The reasons for discontinuation were informed patient decision (4 patients); YMDD mutation (2); self-discontinuation without physician consultation (2); and pregnancy (1). Of those who discontinued lamivudine, serum HBV DNA was undetectable at a mean of 30 (range, 9-47) months' follow-up in 6 (66.7%) of 9 patients. Lamivudine treatment was resumed in 3 patients on reappearance of HBV DNA, and a subsequent rapid decline in the serum HBV DNA was observed. The liver-related mortality rate was not significantly higher in patients who discontinued treatment compared with continuously treated patients (both, 0%). The between-group difference in overall mortality rates was not significant (22.2% and 18.2%, respectively).

CONCLUSIONS

This case series illustrated a variety of clinical situations in which discontinuation of lamivudine treatment prescribed for posttransplantation hepatitis flare may occur. However, liver-related mortality was not increased in these patients compared with those who continued lamivudine treatment.

High prevalence of occult hepatitis B virus infection in Taiwanese intravenous drug users

The epidemiology and impact of occult HBV infection in intravenous drug users remain largely unknown. The aim of the study was to investigate the prevalence of occult HBV infection among intravenous drug users in Taiwan. Molecular assays were used to determine the level of serum HBV DNA and the genotype in 304 intravenous drug users negative for both HBsAg and anti-HCV. Of 304 intravenous drug users, 125 (41.1%) were positive for serum HBV DNA. The genotype distribution of HBV was as follows: B, 55 (44%); C, 29 (23%); and mixed B and C infections, 41 (33%). The mean and median serum HBV DNA levels in 125 intravenous drug users with occult HBV infection were 4.0 +/- 0.6 and 4.0 log(10) copies/ml, respectively. The mean serum HBV DNA level in carriers with mixed genotype B and C infections was significantly higher than those infected with HBV genotype B or genotype C alone (mean, 4.2 +/- 0.6 log(10) vs. 3.9 +/- 0.5 log(10), and 3.9 +/- 0.7 log(10) copies/ml, P = 0.01 and 0.05, respectively). The amino acid sequence determination of HBV surface gene in 20 intravenous drug users with occult HBV infection selected at random showed no mutation of amino acid at codon 145. In conclusion, the prevalence of occult HBV infection and mixed HBV genotype infections are not uncommon in intravenous drug users residing in an HBV endemic areas. In addition, intravenous drug users with occult mixed genotype B and C infections have significantly higher viral loads than those with occult infection of single HBV genotype.

Noninvasive tests for the prediction of significant hepatic fibrosis in hepatitis C virus carriers with persistently normal alanine aminotransferases

BACKGROUND

The diagnostic value of Doppler and various noninvasive indices in predicting significant hepatic fibrosis in hepatitis C virus (HCV) carriers with persistently normal alanine aminotransferases (PNALT) is unknown.

METHODS

Seventy-nine treatment-naïve HCV carriers with PNALT, who received Doppler ultrasonography and percutaneous liver biopsies, were enrolled in the study. Doppler indices, including portal vein velocity (PVV), hepatic arterial resistive index (HARI), hepatic arterial pulsatility index (HAPI), splenic arterial resistive index (SARI), and splenic arterial pulsatility index (SAPI), were compared with known biochemical indices used in HCV carriers with elevated ALT levels, including aspartate aminotransferase (AST) to platelet ratio index (APRI), age-platelet index (API), and AST to ALT ratio (AAR), for the diagnostic accuracy of significant hepatic fibrosis.

RESULTS

SAPI was the most discriminatory index among the Doppler indices (P<0.001). By comparing areas under the receiver-operating characteristic (AUROC) of SAPI with various biochemical indices, SAPI was superior to APRI, API, and AAR for predicting significant fibrosis (> or =F2) (0.862 vs. 0.673, 0.639, 0.504). SAPI set at 0.85 and 1.10 had a sensitivity of 96.7% and 66.7%, a specificity of 44.6% and 96.0%, a positive predictive value of 41.4% and 87.1%, and an negative predictive value of 97% and 87.7% in predicting significant fibrosis.

CONCLUSIONS

This study indicates that SAPI is the most useful index among Doppler and biochemical indices for the detection of significant hepatic fibrosis in HCV carriers with PNALT levels.

Viral factors correlate with hepatitis B e antigen seroconverson in patients with chronic hepatitis B

BACKGROUND/AIMS

Seroconversion (SC) from hepatitis B envelope antigen (HBeAg) to anti-HBe usually indicates lower viral loads, resolved hepatitis activity and improved long-term outcomes. However, the role of viral factors in the development of SC remains largely unknown. We thus comprehensively studied these factors in 25 patients with sustained HBeAg SC and seven control patients with sustained loss of HBeAg.

METHODS

We determined viral factors in serum samples obtained 1 year before, 6 months before, 3 months before, at the time of, 6 months after and 1 year after HBeAg SC or HBeAg loss. Precore A1896 and basal core promoter T1762/A1764 mutants were determined by polymerase chain reaction (PCR)-based assays. Serum HBV levels were determined by a real-time PCR assay.

RESULTS

We found that decline of serum viral load, frequently accompanied by hepatitis exacerbation, occurred within 1 year before HBeAg SC. The proportions of precore and BCP mutations also increased gradually throughout the process of HBeAg SC. The virologic features were similar between HBeAg SC group and HBeAg loss group. Before HBeAg SC or loss, genotype B patients had higher serum viral loads and lower proportions of BCP mutation compared with genotype C patients.

CONCLUSION

Our findings suggested that viral factors correlate with the development of sustained HBeAg SC or loss.

Inhibition of 12-lipoxygenase during baicalein-induced human lung nonsmall carcinoma H460 cell apoptosis

Baicalein is known as a 12-lipoxygenase (12-LOX) inhibitor. The 12-LOX is found to be involved in the progression of human cancers and the inhibitor of 12-LOX offers a target for the prevention cancer. We demonstrated the inhibitory effect of baicalein on the gene and protein expression of 12-LOX in H460 human lung nonsmall carcinoma cell line. Treatment of baicalein inhibited the growth of H460 cells in a dose-dependent manner. Following 24h exposure to 50muM baicalein, cell cycle analysis revealed an increase in the cell population in S-phase. During the S-phase arrest, baicalein decreased the protein levels of cdk1 and cyclin B1, which are the regulating proteins of S-phase transition to G2/M-phase, in this study. Furthermore, baicalein induced the most of H460 cell apoptosis after treatment for 48h. H460 cells formed vesicles and apoptotic body, and then floated after treatment with baicalein. Baicalein-induced H460 cell apoptosis was confirmed by DNA condensation and fragmentation. Baicalein-induced apoptosis were also accompanied by decreasing in Bcl-2 and proform of caspase-3 and increasing p53 and Bax protein levels. Pretreatment with a specific caspase-3 inhibitor, Ac-DEVD-CHO, partially reduced baicalein-induced cell death, indicating baicalein induces apoptosis is partially dependent on caspase-3 pathway in H460 cells. These data suggest that baicalein, a 12-LOX inhibitor, inhibits the proliferation of H460 cells via S-phase arrest and induces apoptosis in association with the regulation of molecules in the cell cycle and apoptosis-related proteins.

Successful Treatment of Hepatitis B Virus Infection With Lamivudine After Heart Transplantation

Patients with hepatitis B virus (HBV) infection have a higher morbidity and mortality after heart transplantation (HT). HBV infection is endemic in Taiwan. We studied the effect of lamivudine treatment of HBV infection after HT. From July 1987 to July 2005, 252 patients underwent HT. All recipients and donors underwent routine screening of hepatitis B surface antigen (HBsAg), hepatitis B e antigen, antibody to hepatitis B surface antigen, antibody to hepatitis B core antigen, antibody to hepatitis B e antigen, and an alanine aminotransferase (ALT) level before HT. When ALT was two times greater than the upper limit of normal or serum bilirubin was higher than 3 mg/dL in HBsAg-positive patients, HBV-DNA were checked by a branched DNA assay or polymerase chain reaction. When HVB-DNA was greater than 100,000 copies/mL, lamivudine (100 mg per day) was prescribed indefinitely. There were 14 patients under lamivudine treatment after HT, among whom, none suffered severe adverse reactions from lamivudine. Four patients died: one due to end-stage cirrhosis while awaiting liver transplantation at 14 months after HT. Two died of sudden death at 54 months and 138 months after HT. Another died of diffuse B cell lymphoma at 62 months after HT. All the survivors have normal ALT and undetectable HBV-DNA after lamivudine treatment. But the YMDD mutant was detected in two patients. With successful treatment of HBV infection in HT, it is not necessary to exclude HBV infection patients from HT.

Role of hepatitis B virus precore/core promoter mutations and serum viral load on noncirrhotic hepatocellular carcinoma: a case-control study

BACKGROUND

Apart from the presence of liver cirrhosis, hepatitis B virus (HBV) factors have also been shown to play a role in the development of hepatocellular carcinoma (HCC). Studying HBV-related noncirrhotic HCC may help clarify the effect of viral factors.

METHODS

In a hospital-based, age- and genotype-matched study, we aimed to determine the role played by basal core promoter (BCP) T1762/A1764 mutation, precore A1896 mutation, and serum viral load in noncirrhotic hepatocarcinogenesis by comparing 44 patients with HBV-related noncirrhotic HCC, 45 patients with chronic hepatitis B, and 42 patients with HBV-related cirrhotic HCC. HBV genotype, precore and BCP mutations, and viral load were determined by molecular assays.

RESULTS

In univariate analysis, statistically significant odds ratios were obtained for male sex (P=.005) and BCP T1762/A1764 mutation (P=.0003) in patients with noncirrhotic HCC, compared with patients with chronic hepatitis B. By multiple logistic regression analysis, male sex, BCP T1762/A1764 mutation, and viral load >or=10(5) copies/mL were independently associated with the risk of noncirrhotic HCC. The virologic characteristics were similar between patients with cirrhotic HCC and those with noncirrhotic HCC.

CONCLUSIONS

Our results suggest that BCP T1762/A1764 mutation and higher viral load may be involved in the carcinogenesis of cirrhotic and noncirrhotic HCC.