Machine learning for individualized prediction of hepatocellular carcinoma development after the eradication of hepatitis C virus with antivirals.

BACKGROUND AND AIMS: Accurate risk stratification for hepatocellular carcinoma (HCC) after achieving a sustained viral response (SVR) is necessary for optimal surveillance. We aimed to develop and validate a machine learning (ML) model to predict the risk of HCC after achieving an SVR in individual patients. METHODS: In this multicenter cohort study, 1742 patients with chronic hepatitis C who achieved an SVR were enrolled. Five ML models were developed including DeepSurv, gradient boosting survival analysis, random survival forest (RSF), survival support vector machine, and a conventional Cox proportional hazard model. Model performance was evaluated using Harrel' c-index and was externally validated in an independent cohort (977 patients). RESULTS: During the mean observation period of 5.4 years, 122 patients developed HCC (83 in the derivation cohort and 39 in the external validation cohort). The RSF model showed the best discrimination ability using seven parameters at the achievement of an SVR with a c-index of 0.839 in the external validation cohort and a high discriminative ability when the patients were categorized into three risk groups (P <0.001). Furthermore, this RSF model enabled the generation of an individualized predictive curve for HCC occurrence for each patient with an app available online. CONCLUSIONS: We developed and externally validated an RSF model with good predictive performance for the risk of HCC after an SVR. The application of this novel model is available on the website. This model could provide the data to consider an effective surveillance method. Further studies are needed to make recommendations for surveillance policies tailored to the medical situation in each country. IMPACT AND IMPLICATIONS: A novel prediction model for HCC occurrence in patients after hepatitis C virus eradication was developed using machine learning algorithms. This model, using seven commonly measured parameters, has been shown to have a good predictive ability for HCC development and could provide a personalized surveillance system.

Impact of Obesity and Heavy Alcohol Consumption on Hepatocellular Carcinoma Development after HCV Eradication with Antivirals.

BACKGROUND AND AIMS: It remains unclear whether obesity increases the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C who achieved a sustained virological response (SVR) with antiviral therapy. METHODS: In this multicenter cohort study, we enrolled patients with chronic hepatitis C who achieved SVR with interferon (IFN)-based therapy (IFN group) or direct-acting antiviral (DAA) therapy (DAA group) between January 1, 1990, and December 31, 2018. The patients underwent regular surveillance for HCC. Cumulative incidence of and the risk factors for HCC development after SVR were assessed using the Kaplan-Meier method and Cox proportional hazard regression analysis, respectively. RESULTS: Among 2,055 patients (840 in the IFN group and 1,215 in the DAA group), 75 developed HCC (41 in the IFN group and 34 in the DAA group) during the mean observation period of 4.1 years. The incidence rates of HCC at 1, 2, and 3 years were 1.2, 1.9, and 3.0%, respectively. Multivariate analysis revealed that in addition to older age, lower albumin level, lower platelet count, higher alpha-fetoprotein level, and absence of dyslipidemia, obesity (body mass index ≥25 kg/m2) and heavy alcohol consumption (≥60 g/day) were independent risk factors for HCC development, with adjusted hazard ratio (HR) of 2.53 (95% confidence interval [CI]: 1.51-4.25) and 2.56 (95% CI: 1.14-5.75), respectively. The adjusted HR was not significant between the 2 groups (DAA vs. IFN; HR 1.19, 95% CI: 0.61-2.33). CONCLUSIONS: Obesity and heavy alcohol consumption increased the risk of HCC development after SVR.

Efficacy and safety of glecaprevir/pibrentasvir in patients with hepatitis C virus infection aged ≥75 years.

AIM: Opportunities to treat older patients with hepatitis C virus infection have increased. We investigated the efficacy and safety of glecaprevir/pibrentasvir in patients with HCV infection aged ≥75 years. METHODS: We retrospectively evaluated 131 patients with hepatitis C virus infection treated with glecaprevir/pibrentasvir at nine institutions in Japan. The patients were divided into two groups according to their age: the elderly group (n = 43, aged ≥75 years) and younger group (n = 88, aged <75 years). We compared the clinical characteristics, virologic response and adverse events between the two groups. The predictive factors for adverse events were also assessed. RESULTS: The presence of cirrhosis (27.9%), a history of hepatocellular carcinoma (23.3%) and comorbidities (88.4%) were more frequently observed in the elderly group than in the younger group. Six (14.0%) patients in the elderly group and 19 (21.6%) in the younger group dropped out before the sustained virologic response 12 assessment. In the intention-to-treat population, 86.0% in the elderly group and 78.4% in the younger group achieved sustained virologic response 12 (P = 0.30). In the modified intention-to-treat population, all patients achieved sustained virologic response 12. A total of 27.5% of patients experienced adverse events. The most frequently observed adverse events was pruritus, and was significantly associated with female sex, the presence of hemodialysis and serum albumin at baseline <4.0 g/dL. CONCLUSION: Glecaprevir/pibrentasvir therapy was effective and well tolerated, even in elderly patients with hepatitis C virus infection aged ≥75 years. Geriatr Gerontol Int 2020; ••: ••-••.

Impact of resistance-associated variant dominancy on treatment in patients with HCV genotype 1b receiving daclatasvir/asunaprevir.

Sustained virological responses (SVR) by daclatasvir (DCV) and asunaprevir (ASV) therapy for genotype 1b hepatitis C virus (HCV) infected patients has been significantly affected by pre-existence of Y93 H resistance-associated variants (RAVs) in the non-structural protein 5A (NS5A) region. The aim of this study was to elucidate the dominancy of naturally occurring RAVs in viral quasispecies on treatment outcomes in patients with HCV. In total, 138 patients were prospectively selected from 152 patients treated with DCV and ASV, where evaluation of treatment outcomes at 12 weeks post-treatment was possible. Pre-treatment RAVs in the non-structural protein 3 and NS5A regions were detected by polymerase chain reaction (PCR)-Invader assays, and the ratio of Y93H RAVs in viral quasispecies was measured by quantitative PCR-Invader assay. Among 25 patients detected the Y93H RAV, the Y93H ratio was 1-25% in 5 patients, 26-75% in 7 patients, and ≥76% in 13 patients. Overall, SVR at 12 weeks after the completion of treatment (SVR12) was 91% (125/138), and those with Y93H ratios of <1%, 1-25%, 26-75%, and ≥76% were 99%, 100%, 71%, and 23%, respectively. Thus, the SVR12 decreased as the HCV Y93H ratio increased (P < 0.0001). The dominancy of pre-treatment RAVs of DCV and ASV affected its treatment outcomes, suggesting that evaluating the dominancy of HCV RAVs could be required for every other direct-acting antiviral agent treatments. J. Med. Virol. 89:99-105, 2017. © 2016 Wiley Periodicals, Inc.

Resistance mutations of hepatitis B virus in entecavir-refractory patients.

The emergence of resistance mutations in the reverse transcriptase gene of hepatitis B virus (HBV) is associated with treatment failure. Entecavir (ETV) is one of the most potent anti-HBV reagents; it has a very low resistance rate and is used as the first-line treatment for chronic hepatitis B. In this study, we isolated HBVs in 4 ETV-refractory patients (2 with viral breakthrough, 1 with partial virological response, and 1 with flare-up) and assessed ETV resistance using replication-competent 1.38-fold HBV genome-length molecular clones. The full genome sequences of infected HBVs in ETV-refractory patients were determined. The HBV molecular clones were generated with the patient-derived sequences. After transfection of these molecular clones into HepG2 cells, viral replications and ETV susceptibilities were evaluated by measuring the amount of intracellular core-particle-associated HBV DNA using Southern blotting and real-time polymerase chain reaction. Among these cases, ETV-resistant variants were detected in 2 patients with viral breakthrough and responsible amino acid mutations in reverse transcriptase were successfully identified in these variants. No ETV-resistant mutation was detected in the other cases. The identified ETV-resistant mutations did not confer resistance to tenofovir disoproxil fumarate. Conclusion: The HBV replication model with patient-derived sequences is useful for assessing replication efficiency, susceptibility to anti-HBV reagents, and responsible resistance mutations and can aid in choosing the appropriate treatment strategy for treatment-failure cases of chronic hepatitis B. (Hepatology Communications 2017;1:110-121).

Acute hepatitis B of genotype H resulting in persistent infection.

A 47-year-old man presented with general fatigue and dark urine. The laboratory data showed increased levels of hepatic transaminases. The patient was positive for hepatitis B virus (HBV) markers and negative for anti-human immunodeficiency virus. The HBV-DNA titer was set to 7.7 log copies/mL. The patient was diagnosed with acute hepatitis B. The HBV infection route was obscure. The serum levels of hepatic transaminases decreased to normal ranges without any treatment, but the HBV-DNA status was maintained for at least 26 mo, indicating the presence of persistent infection. We isolated HBV from the acute-phase serum and determined the genome sequence. A phylogenetic analysis revealed that the isolated HBV was genotype H. In this patient, the elevated peak level of HBV-DNA and the risk alleles at human genome single nucleotide polymorphisms s3077 and rs9277535 in the human leukocyte antigen-DP locus were considered to be risk factors for chronic infection. This case suggests that there is a risk of persistent infection by HBV genotype H following acute hepatitis; further cases of HBV genotype H infection must be identified and characterized. Thus, the complete determination of the HBV genotype may be essential during routine clinical care of acute hepatitis B outpatients.

High levels of hepatitis B virus after the onset of disease lead to chronic infection in patients with acute hepatitis B.

BACKGROUND: Some patients with acute hepatitis B virus (HBV) infection develop chronic infection. However, the method for identifying these patients has not been established. METHODS: We followed 215 Japanese patients with acute HBV infection until the clearance of hepatitis B surface antigen (HBsAg) or the development of chronic infection. Levels of HBsAg and HBV DNA were serially monitored from the onset. RESULTS: Of the 215 patients, 113 (52.5%) possessed HBV genotype A, 26 (12.0%) genotype B, and 73 (34.0%) genotype C. Twenty-one of the 215 (9.8%) developed chronic infection, with the persistence of HBsAg for >6 months. The rate of chronicity of genotype A, B, and C was 12.4%, 3.8%, and 8.2%. Of the 21 patients, only 6 (2.8%) patients, including 5 with genotype A, failed to clear HBsAg within 12 months. Levels of HBsAg at 12 weeks and HBV DNA at 4 weeks were useful for distinguishing the patients who became chronic from those who did not (P < .001 and P < .001, respectively). Likewise, the levels of HBsAg at 12 weeks and HBV DNA at 8 weeks were useful for discriminating between the patients who lost HBsAg within 12 months and those who did not (P < .01 and P < .05, respectively). CONCLUSIONS: In acute HBV infection, clearance of HBV may happen between 6 and 12 months from the onset. Only those who fail to clear HBV within 12 months from the onset may develop chronic infection.

Short-term prolongation of pegylated interferon and ribavirin therapy for genotype 1b chronic hepatitis C patients with early viral response.

AIM: We tailored extended treatments using pegylated interferon (PEG IFN) and ribavirin (RBV) to viral responses after initiation of therapy and investigated the efficacy and safety of its therapy for chronic hepatitis C (CHC) patients. METHODS: Eighty-two genotype 1b CHC patients were enrolled in the present study. All patients received PEG IFN-alpha-2b and weight-based RBV therapy. We defined a viral response in which serum HCV-RNA is undetectable at week 4 as rapid viral response (RVR), detectable at week 4 and undetectable by week 12 as early viral response (EVR), and detectable at week 12 and undetectable by week 24 as late viral response (LVR). We set the treatment duration depending on viral response; 48 weeks for RVR patients and 72 weeks for LVR. Furthermore, EVR patients received a short-term extension of treatment duration to 52-60 weeks. We prospectively investigated sustained viral response (SVR) rates of these groups. RESULTS: Overall SVR rate for the total patient group was 57.3%. SVR rates of the RVR, EVR and LVR patients were 100%, 80.5% and 40.0%, respectively. Nine patients could not complete this treatment protocol. Baseline platelet count and mutation in the interferon sensitivity-determining region of NS5A were significant independent predictors of SVR, and amino acid substitution of the core region was a significant independent predictor of non-viral response by multivariate logistic regression analyses. CONCLUSION: The results indicate that short-treatment extension of PEG IFN plus RBV treatment protocols in EVR patients can improve overall SVR rates.

Effect of treatment with interferon alpha-2b and ribavirin in patients infected with genotype 2 hepatitis C virus.

AIM: Nearly 20% of chronic hepatitis C (CHC) patients with genotype 2 hepatitis C virus (HCV) infection are not curable, even by interferon (IFN)-ribavirin combination therapy. The aim of this study is to investigate the factors that determine the efficacy of combination therapy in patients with genotype 2 HCV infection. METHODS: Fifty patients with CHC who underwent a treatment of 6 MU IFN alpha-2b with ribavirin for 24 weeks were retrospectively analyzed. RESULTS: All the patients showed no serum HCV-RNA within 12 weeks after starting the therapy. Forty-one of the 50 patients (82%) achieved a sustained virological response (SVR). The age, sex, genotype (2a vs. 2b) and grade/stage of the liver by histopathology and pretreatment viral load werenot different between the sustained responders and relapsers. Univariate analysis showed that an earlier viral clearance from blood and a larger number of amino acid substitutions in the interferon sensitivity determining region (ISDR) were predictors of SVR. Multivariate analysis showed that a large number of amino acid substitutions in the ISDR was a predictor of SVR. CONCLUSION: The characterization of the amino acid sequences of ISDR may be helpful for predicting a relapse after combination therapy in patients with genotype 2 HCV infection.

Amino acid substitutions in the S region of hepatitis B virus in sera from patients with acute hepatitis.

BACKGROUND: An increase in the number of acute hepatitis patients with hepatitis B virus (HBV) of non-indigenous genotypes may reduce the efficacy of vaccination against HBV. METHODS: We have determined the amino acid (aa) sequences in the major hydrophilic region (MHR) in the S region of HBV in patients with acute hepatitis B and compared those with the ones from HBV strains used for the production of HBV vaccines commercially available in Japan. RESULTS: Of 48 patients studied, 11 were infected with genotype A, 11 with genotype B and 26 with genotype C HBV. The aa sequences of the nine genotype A isolates were the same as the aa sequence of J02205 which is used for the production of one of the commercially available recombinant vaccines. The aa sequences of the 11 genotype B isolates differed from the aa sequence of J02205 in two or three amino acids. Of the26 genotype C isolates, 22 had the same aa sequence as X01587 which is used for the production of another recombinant vaccine. The remaining genotype C isolates had aa substitutions at aa131, which have a potential to alter the hydropathy and the three-dimensional structure of the MHR. The differences among the three current HBV vaccines in aa sequences in the MHR theoretically alter the hydropathy and three-dimensional structure. CONCLUSION: Our results suggest that the transmission of HBV isolates with different genotypes or with aa substitutions in the MHR might reduce the efficacy of currently available HBV vaccines in the protection of HBV infections.

Molecular epidemiology of hepatitis A virus in metropolitan areas in Japan.

BACKGROUND: Transmission routes of hepatitis A virus (HAV) in Japan have changed. The present study investigated changes of transmission routes in relation to genetic drift. METHODS: All 60 patients who were admitted between 1993 and 2003 with a diagnosis of hepatitis A were retrospectively analyzed. Nucleotide sequences of the VP1/2A region of the HAV recovered from their sera were determined. RESULTS: The suspected transmission routes were household contact, 19 (31%); food or waterborne, 16 (27%); homosexual activity, 11 (18%); international travel, 4 (7%); and unknown 10. (17%). The 11 patients presumably infected through homosexual activity were found exclusively in 1998 and 1999. The proportion of patients exposed through homosexual behavior and household contact was higher in those 2 years than in other years. Nucleotide sequences could be determined for 58 patients. Fifty-seven of the 58 sequences belonged to genotype IA HAV, with less than 10% nucleotide diversity. Of the 27 sequences isolated during 1998 and 1999, 25 had an identical nucleotide sequence regardless of the suspected transmission route. In contrast, sequences obtained in the other years differed from one another. A phylogenetic tree constructed from sequences recovered from patients without a history of travel abroad showed several clusters. CONCLUSIONS: Our results suggest that (1) HAV acquired through homosexual activity may be transmitted to nonhomosexual individuals; (2) hepatitis A in metropolitan areas in Japan is caused mainly by sporadic infection with genotype IA HAV; and (3) several subtypes of genotype IA HAV are endemic in Japan.

Risk factors for retinopathy associated with interferon alpha-2b and ribavirin combination therapy in patients with chronic hepatitis C.

AIM: To elucidate the frequency and risk factors for retinopathy in patients with chronic hepatitis C who are treated by interferon-ribavirin combination therapy. METHODS: We prospectively analyzed 73 patients with histologically confirmed chronic hepatitis C, who underwent combination therapy for 24 wk. Optic fundi were examined before, and 2, 4, 12 and 24 wk after the start of combination therapy. RESULTS: Fourteen patients (19%) developed retinopathy, which was initially diagnosed by the appearance of a cotton wool spot in 12 patients. Retinal hemorrhage was observed in 5 patients. No patient complained of visual disturbance. Retinopathy disappeared in 9 patients (64%) despite the continuation of combination therapy. However, retinopathy persisted in 5 patients with retinal hemorrhage. A comparison of the clinical background between the groups with and without retinopathy showed no significant differences in age, gender, viral genotype, RNA level, white blood cell count, platelet count, prothrombin time, complications by diabetes mellitus or hypertension, or pretreatment arteriosclerotic changes in the optic fundi. However, multiple logistic regression analysis revealed that complication by hypertension was observed with a high frequency in the group with retinopathy (P = 0.004, OR = 245.918, 95% CI = 5.6-10786.2). CONCLUSION: Retinopathy associated with combination therapy of interferon alpha-2b and ribavirin tends to develop in patients with hypertension.

Distinct geographic distributions of hepatitis B virus genotypes in patients with acute infection in Japan.

Genotypes of hepatitis B virus (HBV) were determined in 145 patients with acute hepatitis B from various districts in Japan to establish their geographic distribution and evaluating the influence on the clinical illness and outcome. Genotypes were A in 27 (19%) patients, B in 8 (5%), C in 109 (75%) and mixed with B and C in the remaining one (1%). Genotype A was more frequent in metropolitan than the other areas (21/69 (30%) vs. 6/76 (8%), P < 0.001). On phylogenetic analysis, seven of the nine (78%) HBV/A isolates selected at random clustered with those from Europe and the United States, while the remaining two with those of subgroup A' prevalent in Asia and Africa. Maximum ALT levels were lower (2069 +/- 1075 vs. 2889 +/- 1867 IU/L, P = 0.03) and baseline HBV DNA titers were higher (5.90 +/- 1.45 vs. 5.13 +/- 1.36 log genome equivalents (LGE)/ml, P = 0.002) in patients infected with genotype A than C. Hepatitis B surface antigen persisted longer in patients infected with genotype A than C (1.95 +/- 1.09 vs. 1.28 +/- 1.42 months, P = 0.02). HBV infection became chronic in one (4%) patient with genotype A and one (1%) with genotype C infection. Fulminant hepatic failure developed in none of the patients with genotype A, one (13%) with genotype B and five (5%) with genotype C. The point mutation in the precore region (A1896) or the double mutations in the basic core promoter (BCP) region (T1762/A1764) were detected in none of the patients with genotype A, two (25%) with genotype B and 27 (26%) with genotype C. In conclusion, genotype A is frequent in patients with acute hepatitis B in metropolitan areas of Japan, probably reflecting particular transmission routes, and associated with longer and milder clinical course than genotype C.

Short-term lamivudine for the treatment of chronic hepatitis B.

Short-term lamivudine and its withdrawal were evaluated as regards an immunomodulatory therapy of chronic hepatitis B. Lamivudine was given for 3 or 6 months to 23 patients with chronic hepatitis B who were infected with hepatitis B virus (HBV) genotype C, including 15 with hepatitis B e antigen (HBeAg) and 8 without it. It decreased serum levels of alanine aminotransferase (ALT) and HBV DNA in HBeAg-positive patients. Flare-ups of ALT and HBV DNA after treatment were observed in most patients, and 4 of the 12 (33%) patients with 6-month lamivudine treatment remained in remission 6 months after withdrawal of the therapy. In HBeAg-negative patients, however, flare-ups of ALT and HBV DNA were mild. Normalization of ALT and a decrease in serum HBV DNA were accomplished in 6 of the 9 (75%) patients. Breakthroughs or serious side effects were not observed in any patients. Short-term lamivudine is safe and may offer a therapeutic option to patients with chronic hepatitis B.

Detection, using a novel method, of a high prevalence of cryoglobulinemia in persistent hepatitis C virus infection.

To elucidate precisely the prevalence and significance of cryoglobulinemia in hepatitis C, we examined the prevalence of serum cryoglobulin (CG) among 232 consecutive hepatitis C virus carriers (23 asymptomatic carriers, 164 with chronic hepatitis, 45 with cirrhosis), 30 consecutive hepatitis B virus carriers and 100 age- and sex-matched healthy volunteers. We used a gel-diffusion procedure that detects CG with greater sensitivity and specificity than the conventional precipitation method. Among the 232 patients, 166 were tested for the presence or absence of CG by the precipitation method also, which showed 60 (36.1%) patients to be positive for CG. On the other hand, 164 of the 232 patients (70.7%) were positive for CG using the diffusion method. 5 (16.7%) of the 30 HBV carriers and 2 (2%) of the healthy volunteers also were positive for CG using the gel-diffusion procedure. CG was detected more frequently among the patients with chronic hepatitis or cirrhosis than the asymptomatic carriers. In spite of the high prevalence of CG positivity, only one patient had symptoms related to cryoglobulinemia. Positivity for CG was not related to viral serogroup, viral load or the presence of antinuclear antibody, but it was related closely to CH50: 58 of 63 (92.1%) patients with lower levels of CH50 were positive for serum CG. In conclusion, cryoglobulinemia is a very common feature of chronic hepatitis C.

Precore and core promoter mutations, hepatitis B virus DNA levels and progressive liver injury in chronic hepatitis B.

BACKGROUND/AIMS: To elucidate the viral factors responsible for progressive liver injury in chronic hepatitis B. METHODS: We analyzed 179 persistently infected patients (21 asymptomatic carriers, 126 with chronic hepatitis and 32 with cirrhosis) with genotype C hepatitis B virus (HBV). HBeAg/anti-HBe, levels of HBV DNA, mutations in the basic core promoter (BCP) region at nucleotides 1762/1764 and mutation in the precore (preC) region at nucleotide 1896 were determined. Serial samples from 18 patients also were analyzed. RESULTS: HBeAg/anti-HBe and HBV DNA levels per se were not related to liver fibrosis. The frequency of BCP mutations increased with progression of liver fibrosis. Although the preC mutation was detected more often among the LC group, the role of this mutation in progression of fibrosis seems less than that of the BCP mutations. Sequential analysis showed that (1) rapidly progressing cases were positive continuously for double mutations in the BCP with a wild-type precore sequence, and (2) asymptomatic cases with anti-HBe acquired the preC mutation during their clinical course. CONCLUSIONS: Double mutations in the BCP region at nucleotide 1762/1764 are closely related to progression of chronic liver disease. Acquisition of mutation in the preC region at nucleotide 1896 may contribute to inactivation of chronic liver disease.