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PubMed2002

Preliminary results: outcome of liver transplantation for hepatitis B virus varies by hepatitis B virus genotype.

Hepatitis B virus (HBV) is a leading cause of liver failure throughout the world. HBV has seven different genotypes based on variations within the viral nucleotide sequence. Initially, patients who underwent liver transplantation for HBV had high recurrence rates and poor survival. Recently, improved outcomes have been reported when patients are administered hepatitis B immunoglobulin (HBIg) infusions to maintain high serum hepatitis B surface antibody titers after transplantation. Unfortunately, recurrence rates are still high in patients with active pretransplant HBV replication. The aims of this study are to evaluate the impact of HBV genotype on pretransplantation HBV replication and posttransplantation HBV recurrence rate, morbidity, and mortality. Sera from 22 patients who underwent transplantation for HBV at our center were tested for HBV genotype by an enzyme-linked immunosorbent assay technique using monoclonal antibodies to the pre-S2 region. All patients were administered HBIg after transplantation; 5 patients were administered both lamivudine and HBIg. HBV genotypes were distributed as follows: genotype A (10 patients), genotype C (6 patients), genotype D (5 patients), and genotype E (1 patient). Pretransplantation HBV replication was most common with genotype A (80%), whereas less so with genotypes C (33%) and D (40%). Nine patients (41%) developed recurrent HBV infection: genotype A (2 patients; 20%), genotype C (3 patients; 50%), and genotype D (4 patients; 80%). Mortality was greatest with genotype D (40%). Our data suggest that patients with genotype A have the lowest risk for HBV recurrence despite having the highest rate of pretransplantation HBV viral replication. Patients with genotype D appear to have the highest risk for HBV recurrence and mortality. Additional larger multicenter studies are needed to confirm these findings.

Adult↗
PubMed2005

Epidemiological and virological characteristics of 2 subgroups of hepatitis B virus genotype C.

BACKGROUND: We aimed to investigate the characteristics of hepatitis B virus (HBV) genotype C subgroups in Hong Kong and their relationship with HBV genotype C in other parts of Asia. METHODS: Full-genome nucleotide sequences of 49 HBV genotype C isolates from Chinese patients with chronic hepatitis B were compared with the sequences of 69 HBV genotype C isolates and 12 non-genotype C isolates in the GenBank database. Phylogenetic analysis was performed to define the subgroups of HBV genotype C on the basis of >4% heterogeneity of the entire HBV genome. RESULTS: HBV in 80% of patients in Hong Kong belonged to a subgroup predominantly found in Southeast Asia (Vietnam, Thailand, Myanmar, and southern China) designated as HBV genotype "Cs," and HBV in the remaining 20% of patients belonged to another subgroup, predominantly found in the Far East (Korea, Japan, and northern China), designated as HBV genotype "Ce." Overall, the mean+/-SD nucleotide sequence difference between HBV genotype Cs and HBV genotype Ce was 4.2%+/-0.3%. When HBV genotype Cs and HBV genotype Ce were compared among patients in Hong Kong, HBV genotype Cs was associated with a higher tendency to develop basal core promoter mutations (80% vs. 50%; P=.14), a higher prevalence of C at nucleotide 1858 (95% vs. 0%; P<.001), and a lower prevalence of precore stop codon mutations (5% vs. 50%; P=.002). CONCLUSIONS: HBV genotype C can be differentiated into 2 subgroups--namely, genotype Ce and genotype Cs--that have different epidemiological distributions and virological characteristics.

Adult↗
PubMed1998

Genotype distribution of hepatitis C virus infection in Greece: correlation with different risk factors and response to interferon therapy.

The aim of this study was to investigate the prevalence of HCV genotypes among Greek patients with chronic hepatitis C and to assess the influence of genotypes and quasi-species populations on efficacy of interferon therapy. Genotypes were determined in 65 patients (18 patients after kidney transplantation, 16 with thalassemia and 31 with no known risk factor) with elevated ALT for more than 6 months and histologically proven chronic hepatitis, using the Inno-Lipa strip assay. The quasi-species were determined using the fluorescence single-strand conformational polymorphism method. Most patients were infected with genotype 3a, namely 61% of patients with kidney transplants (n = 18), 50% of patients with thalassemia (n = 16) and 48% of patients without known risk factors (n = 31). Other genotypes were found including coinfection with different genotypes. In all patients with mixed infection, genotype 3a was present. Thirty-six patients from the last two groups received interferon (3Mio U 3x week) for 1 year. Biochemical and/or virological and histological responses were found in 11/19 patients with genotype 3a (58%), 3/5 with mixed infection, 2/4 with genotype 1b, 2/5 with genotype 2a, 1/4 with genotype 1a and 1/1 with genotype 4. The virus found in non-responders with genotype 3a was genetically more heterogeneous than in responders. These data indicate that (1) the genotype 3a is prevalent in Greek patients (68% of all patients), (2) there is no significant difference regarding genotypes among patients with different risk factors and (3) although based on a small number of patients, the genotype 3a seems to respond better to interferon therapy. Finally, the number of quasi-species may be a factor predictive of response.

Adult↗
PubMed2004

Double point mutation in the core promoter region of hepatitis B virus (HBV) genotype C may be related to liver deterioration in patients with chronic HBV infection.

BACKGROUND AND AIM: Hepatitis B virus (HBV) genotype C has a more severe pathogenesis than genotype B in Japan. We retrospectively investigated the relationship between HBV genotype and the core promoter (CP) (nt 1762 and 1764) and precore (PreC) (nt 1896) mutations of the HBV genome. METHODS: A total of 129 Japanese patients (42 genotype B and 87 genotype C) with chronic HBV infection, living in two different geographical areas in Japan, were evaluated (mean follow-up period 10.1 +/- 3.8 years). In 2000, CP and PreC HBV mutations were analyzed by direct sequencing from sera. Hepatitis B e antigen (HBeAg), HBV DNA and serial alanine aminotransferase (ALT) changes were followed and determined using serological methods. RESULTS: Genotype C patients had significantly higher rates of HBeAg (40.2%vs 2.4%), HBV DNA positivity (75.9%vs 7.1%) and ALT abnormality (71.3%vs 11.9%) than genotype B patients (all P < 0.05). Among genotype B patients, CP wild type (92.9%) was predominant and PreC mutation (88.1%) was predominant. However, among genotype C patients, CP mutation (75.9%) was predominant and PreC mutation (66.7%) was predominant. The CP mutation was found significantly more in genotype C than in genotype B (P < 0.05). Of the 67 patients with ALT abnormality, five (7.5%) genotype B and 62 (92.5%) genotype C patients (31 HBeAg positive and 31 negative) were found. Among the 31 genotype C patients who were HBeAg positive, the combination of CP mutation and PreC wild (54.8%) was predominant, while among the remaining 31 genotype C patients who were HBeAg negative, the combination of CP mutation and PreC mutant (71.0%) was predominant. CONCLUSION: Genotype C might be one of the worse prognostic markers in patients with chronic HBV infection, possibly because of mutation in the CP region.

Adult↗
PubMed2002

Comparative resistance of phage isolates of four genotypes of f-specific RNA bacteriophages to various inactivation processes.

The effect of natural inactivation in freshwater, chlorination, ammonia, extreme pHs, temperature, and salt content on phage inactivation was evaluated on mixtures of F-specific RNA bacteriophage isolates belonging to genotypes I, II, III, and IV. The bacteriophages studied were previously but recently isolated from natural samples, characterized as F-specific RNA bacteriophages and genotyped by plaque hybridization with genotype-specific probes. Natural inactivation in river water was modeled by in situ incubation of bacteriophages inside submerged dialysis tubes. After several days bacteriophages of genotype I showed the highest persistence, which was significantly different from that of bacteriophages of genotype II, IV, or III. The pattern of resistance of phages belonging to the various genotypes to extreme pHs, ammonia, temperature, salt concentration, and chlorination was similar. In all cases, phages of genotype I showed the highest persistence, followed by the phages of genotypes II, III, and IV. The phages of genotypes III and IV were the least resistant to all treatments, and resistance of genotypes III and IV to the treatments was similar. Bacteriophages of genotype II showed intermediate resistance to some of the treatments. The resistance of four phages of genotype I to natural inactivation and chlorination did not differ significantly. These results indicate that genotypes III and IV are much more sensitive to environmental stresses and to treatments than the other genotypes, especially than genotype I. This should be taken into consideration in future studies aimed at using genotypes of F-specific RNA bacteriophages to fingerprint the origin of fecal pollution.

Ammonia↗
PubMed2004

Host cell tropism underlies species restriction of human and bovine Cryptosporidium parvum genotypes.

It has been recognized recently that human cryptosporidiosis is usually caused by Cryptosporidium parvum genotype I ("human" C. parvum), which is not found in animals. Compared to C. parvum genotype II, little is known of the biology of invasion of the human-restricted C. parvum genotype I. The aims of the present study were (i) to explore and compare with genotype II the pathogenesis of C. parvum genotype I infection by using an established in vitro model of infection and (ii) to examine the possibility that host-specific cell tropism determines species restriction among C. parvum genotypes by using a novel ex vivo small intestinal primary cell model of infection. Oocysts of C. parvum genotypes I and II were used to infect HCT-8 cells and primary intestinal epithelial cells in vitro. Primary cells were harvested from human endoscopic small-bowel biopsies and from bovine duodenum postmortem. C. parvum genotype I infected HCT-8 cells with lower efficiency than C. parvum genotype II. Actin colocalization at the host parasite interface and reduction in levels of invasion after treatment with microfilament inhibitors (cytochalasin B and cytochalasin D) were observed for both genotypes. C. parvum genotype II invaded primary intestinal epithelial cells, regardless of the species of origin. In contrast, C. parvum genotype I invaded only human small-bowel cells. The pathogenesis of C. parvum genotype I differs from C. parvum genotype II. C parvum genotype I does not enter primary bovine intestinal cells, suggesting that the species restriction of this genotype is due to host tissue tropism of the infecting isolate.

Actins↗
PubMed2005

Rapid genotyping of hepatitis C virus by primer-specific extension analysis.

Quick and accurate genotyping of hepatitis C virus (HCV) is becoming increasingly important for clinical management of chronic infection and as an epidemiological marker. Furthermore, the incidence of HCV infection with mixed genotypes has clinical significance that is not addressed by most genotyping methods. We have developed a fluorescence-based genotyping assay called primer-specific extension analysis (PSEA) for the most prevalent HCV genotypes and have demonstrated the capacity of PSEA-HCV for detecting mixed-genotype HCV infections. PSEA-HCV detects genotype-specific sequence differences in the 5' untranslated region of HCV in products amplified by the COBAS AMPLICOR HCV Test, v2.0. Simulated mixed HCV infection of plasma with RNase-resistant RNA controls demonstrates that PSEA-HCV can detect as many as five genotypes in one specimen. Furthermore, in dual-genotype simulations, PSEA-HCV can unequivocally detect both genotypes, with one genotype representing only 3.1% of the mixture (313/10,000 IU in starting plasma). Compared to INNO-LiPA HCV II, both assays determined the same genotype for 191/199 (96%) patient specimens (175 subtype and 16 genotype-only identifications). Following the initial evaluation, PSEA-HCV was used routinely to genotype HCV from patient specimens submitted to our laboratory (n=312). Seventeen (5.4%) mixed infections were identified. The distribution of single-infection HCV genotypes in our population was 60.9% type 1 (n=190), 12.8% type 2 (n=40), 20.2% type 3 (n=63), 0.3% type 4 (n=1), and 0.3% other (n=1). In conclusion, PSEA-HCV provides an inexpensive, high-throughput screening tool for rapid genotyping of HCV while reliably identifying mixed HCV infections.

5' Untranslated Regions↗
PubMed2006

Hepatitis B virus genotypes in chronic liver disease patients from New Delhi, India.

AIM: To study the Hepatitis B virus (HBV) genotypes and their effect on the progression and outcome in patients with chronic liver diseases from New Delhi, India. METHODS: Sera from 100 HBV-related chronic liver disease (CLDB) cases were tested for HBV genotype using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Type-specific primers-based PCR (TSP-PCR) targeting to the surface (S) gene encoding hepatitis B surface antigen. RESULTS: Only genotypes A and D were present and genotype D was dominant. Genotype D was present in all CLDB patient categories. The genotype distribution for the 100 patients with CLDB was as follows: genotype A, 16/100 (16%) (7/40- 17% chronic hepatitis B (CHB); 8/47, 17%, HBV-related cirrhosis (CRB); 1/13, 7.6%, HBV-related hepatocellular carcinoma (HCCB); genotype D- 84/100 (84%) (32/40- 80% CHB; 38/47- 81%, CRB; 11/13, 85%, HCCB); genotype A+D, 3/100 (3%) (1/40- 3% CHB; 1/47- 2%, CRB; 1/13, 7.6%, HCCB); C, 0; B, 0; E, 0; F, 0; G 0, H 0; (P<0.01, genotype D vs A). CONCLUSION: Only HBV genotypes A and D were present in patients with CLDB from New Delhi, India. Compared with genotype D, genotype A patients had no significant clinical or biochemical differences (P>0.05). Mixed infection with genotype A and D were seen in 3% of the cases. Genotype D was the dominant genotype prevalent in all patient categories.

Adult↗
PubMed2006

Differences in viral kinetics between genotypes 1 and 3 of hepatitis C virus and between cirrhotic and non-cirrhotic patients during antiviral therapy.

AIM: To evaluate the impact of hepatitis C virus (HCV) infection with genotype 1 or 3 and the presence or absence of liver cirrhosis (LC) in the early viral kinetics response to treatment. METHODS: Naive patients (n = 46) treated with interferon-alpha (IFN-alpha) and ribavirin and followed up with frequent early HCV-RNA determinations were analysed. Patients were infected with genotype 1 (n = 28, 7 with LC) or 3 (n = 18, 5 with LC). RESULTS: The first phase decline was larger in genotype 3 patients than in genotype 1 patients (1.72 vs 0.95 log IU/mL, P < 0.001). The second phase slope decline was also larger in genotype 3 patients than in genotype 1 patients (0.87 vs 0.15 log/wk, P < 0.001). Differences were found in both cirrhotic and non-cirrhotic patients. Genotype 1 cirrhotic patients had a slower 2nd phase slope than non-cirrhotic patients (0.06 vs 0.18 log/wk, P < 0.02). None of genotype 1 cirrhotic patients had a 1st phase decline larger than 1 log (non-cirrhotic patients: 55%, P < 0.02). A similar trend toward a slower 2nd phase slope was observed in genotype 3 cirrhotic patients but the 1st phase slope decline was not different. Sustained viral response was higher in genotype 3 patients than in genotype 1 patients (72% vs 14%, P < 0.001) and in genotype 1 non-cirrhotic patients than in genotype 1 cirrhotic patients (19% vs 0%). A second phase decline slower than 0.3 log/wk was predictive of non-response in all groups. CONCLUSION: Genotype 3 has faster early viral decline than genotype 1. Cirrhosis correlates with a slower 2nd phase decline and possibly with a lower 1st phase slope decline in genotype 1 patients.

Antiviral Agents↗
PubMed1999

HLA-DRB1 genotype influences risk for and severity of rheumatoid arthritis.

OBJECTIVE: To examine how HLA-DRB1 genotypes influence rheumatoid arthritis (RA) risk and clinical severity. METHODS: We performed polymerase chain reaction based DRB1 and tumor necrosis factor (TNF) genotyping of 309 Caucasian RA and 283 Caucasian control subjects. For risk analyses, we grouped the DRB1 alleles encoding each specific shared epitope: *0401 alone, *0404 with *0102, *0405 with *0408 and *0101, and *1001 alone. For estimates of RA outcome, we retrospectively obtained data regarding ARA classification criteria, age of disease onset and disease duration, number of slow acting antirheumatic drugs (SAARD) used, and rheumatoid factor (RF). RESULTS: Homozygous shared-epitope DRB1 genotypes, compound heterozygous genotypes, and simple heterozygous genotypes all conferred elevated relative risk (RR) for RA (RR 4.3, 11.7, and 3.5, respectively). However, compound heterozygous genotypes conferred more risk than either simple heterozygous genotype (RR 3.3, p = 0.004) or homozygous genotype (RR 2.8, p = 0.036). There was a trend toward more compound heterozygous genotypes in the male RA group than in the female RA group (p < 0.1), and male sex was associated with higher frequency of rheumatoid nodules (56 vs 35% for female RA). RA outcome was estimated by number of SAARD used; mean SAARD used was higher in male than in female RA (p < 0.01) and higher in genotypes containing one or 2 shared epitope DRB1 alleles than in those negative for shared epitope DRB1 alleles (p < 0.05). Analyses also suggested that shared epitope DRB1 genotype significantly influenced the occurrence of seropositive RA. Seropositive RA fraction was related to either number of shared epitope alleles (0, 1, or 2) represented in the DRB1 genotype, or, alternatively, to the combination of sex with shared epitope DRB1 genotype. The presence of one or 2 shared epitope DRB alleles influenced the occurrence of high titer seropositive RA as defined by sheep cell agglutination test (p < 0.01). TNFab microsatellite markers and TNF promoter polymorphisms did not influence SAARD number, seropositive RA, or high titer seropositive RA. CONCLUSION: Not all shared epitope DRB1 genotypes conferred the same relative risk, and the male RA group tended to have more compound heterozygous genotypes and more severe RA as indicated by rheumatoid nodules and SAARD usage. DRB1 genotypes with one or 2 shared epitope DRB1 alleles influenced the RA outcome as estimated by numbers of SAARD used and RF.

Alleles↗
PubMed2005

[Relationship between B virus hepatitis genotypes and therapeutic efficacy in early treatment for chronic hepatitis B by using lamivudine].

OBJECTIVE: To investigate the relationship between hepatitis B virus (HBV) genotype and therapeutic efficacy during the early phase of lamivudine treatment. METHODS: Totally 595 patients with chronic hepatitis B were treated with lamivudine 100 mg/day for 12 months. HBV genotypes, contents of HBV DNA, HBeAg/anti-HBe and YMDD mutation after lamivudine treatment for 12 months were determined. The data were analyzed with SPSS software. RESULTS: In 595 patients, 8 (1.4%) were genotype A; 53 (8.9%) genotype B; 360 (60.5%) genotype C; 112 (18.8%) were coinfection of genotype B and C; 14 (2.4%) of A and C; 15 (2.5%) A and B; 6 (1.0%) of A, B, and C, and remaining 27 (4.5%) were unspecified. Patients were treated with lamivudine 100 mg/day for 12 months. Genotype B with HBV DNA levels turned to be negative (HBV DNA < 0.1 ng/L) was 87.2%, genotype C was 89.51%, coinfection of genotype B and C was 93.04% (P > 0.05). HBeAg seroconversion of genotype B was 11.65%, of genotype C was 20.64%, and of coinfection of genotype B and C was 18.57% (P > 0.05). All 69 strains of YMDD mutation were detected after lamivudine treatment for 12 months, in which genotype B was in 16.98%, genotype C in 15.38%, and coinfection of genotype B and C was in 13.86% (P > 0.05). CONCLUSION: There was no difference in HBV genotypes and the rate of development of YMDD mutations, HBeAg seroconversion, descending of HBV DNA level in Chinese patients with chronic hepatitis B.

China↗
PubMed2005

[Hepatitis B virus genotypes and the response to lamivudine therapy].

Hepatitis B virus (HBV) can be classified into eight major genotypes (A-H) that have mainly a geographic distribution. The HBV genotype may influence disease progression, HBeAg seroconversion rates, response to antiviral treatment. The aim of study was to analyze the distribution and frequency of genotypes in patients with chronic hepatitis B. Response to lamivudine 100 mg daily therapy was examined in respect to genotype. Sixty six patients (45 (68,2%) male, 21 (31,8%) female) with chronic hepatits B were enrolled. HBV genotypes were assigned before treatment with INNO-LiPA HBV Genotyping, Innogenetics, N. V., Ghent assay, which is a line probe test based on the reverse hybridization principle. In baseline and after 12 months of treatment serological markers of HBV infection, alanine aminotransferase (ALT) activities and HBV DNA serum levels were tested. Patients with chronic hepatitis B were infected predominantly with genotype A. HBV genotype distribution was: 78,8% for genotype A, 13,6% for genotype D, 1,5% for mixed infection with genotypes A and D. Distribution of genotypes A and D was asymmetrically regardless of sex, HBeAg status, ALT and HBV DNA levels. Four (6,1%) specimens had indeterminate A results by LiPA. There were no significant differences between patients with genotypes A and D regarding age and sex. There were also no significant differences between these two groups regarding rates of HBeAg and anti-HBe positivity, ALT activity and viral load. Twenty months of lamivudine (100 mg daily) therapy resulted in significant decreases in serum HBV DNA and ALT activities in patients with genotype A as well as with genotype D. After 12 months of treatment there were no statistical differences in HBeAg seroconversion rates, ALT activities, viral loads, frequency of HBeAg and anti-HBe between genotypes A and D.

Adult↗
PubMedDate not supplied

High prevalence of hepatitis C virus (HCV) genotype 2 in Italian patients with chronic liver disease.

The prevalence of different genotypes of Hepatitis C virus may vary between geographic areas and it is possible that various genotypes have different pathogenic characteristics. Therefore, 90 consecutive Italian patients anti-Hepatitis C Virus positive with a broad spectrum of chronic liver disease, have been analysed to observe prevalence of various genotypes of Hepatitis C Virus. Genotyping was performed by polymerase chain reaction with a set of nested biotinylated primers, located in 5'UTR region. Genotype 1b and genotype 2a were the most commonly encountered (respectively, 50% and 37%) whereas other genotypes were rare. The unexpected high prevalence of genotype 2a allowed direct comparison of clinical characteristics and response to therapy between patients with genotype 2a and those with 1b. Genotype 1b was more prevalent than 2a in patients over 60 years (29 vs 12) and in those with more severe liver disease (34 vs 16). In a univariate analysis, genotype 2a was associated with less severe liver disease (p = 0.02) and younger age (p = 0.018), in comparison with genotype 1b. Patients with genotype 2a responded to interferon alpha therapy better than those with 1b (p = 0.007). In a multivariate analysis, only younger age was associated with genotype 2a. Genotype 2a (in comparison with 1b) and absence of cirrhosis were independent predictors of response to interferon alpha. In conclusion, genotype 2a is playing an emerging role in younger Italian patients and seems more sensitive than 1b to interferon alpha therapy.

Antiviral Agents↗
PubMed2002

Clinical features and viral sequences of various genotypes of hepatitis B virus compared among patients with acute hepatitis B.

Clinical manifestations and viral sequences of core promoter and precore/core region were compared among various genotypes of hepatitis B virus (HBV) in 25 patients with acute hepatitis. The genotype in patients with acute hepatitis was distributed differently from that among chronic hepatitis patients in Japan, which are predominantly genotypes B and C. Of 25 patients with acute hepatitis, 14 had genotype A, five genotype B and six genotype C. Serum total bilirubin levels were significantly higher in patients with genotype A than in those with genotype C. Prothrombin time was shorter in patients with genotype B than those with genotype A or C. Total bilirubin was lower in patients with short duration of acute hepatitis. The serum ALT value remained above 1000 IU/l for over 10 days in 79% of patients with genotype A. This prolonged duration of hepatitis in patients with genotype A may contribute to hyperbilirubinemia. Sequence analysis revealed no difference in the number of mutations in precore/core regions among the three genotypes. Although the double mutation, A-T and G-A at 1762 and 1764, respectively, was found in two patients each with genotype A and C, these mutations were not related to the hepatitis B e antibody (HbeAg)/hepatitis B e antibody (HbeAb) phenotype. Two of seven patients with thymidine at 1858 also had a G to A mutation at 1896. Thus, the difference in the genotype little influenced the HBeAg/HBeAb phenotype in acute hepatitis patients. Understanding the viral genotypes in acute HBV infection may be valuable in predicting the clinical course of acute hepatitis B (AHB).

Journal Article↗
PubMed2004

Chronic hepatitis C. Genotypes and response to anti-viral therapy among Saudi patients.

OBJECTIVE: The aim of this study is to compare the response of hepatitis C virus (HCV) genotype 4 with other genotypes to anti-viral treatment among Saudi patients in a prospective randomized trial. METHODS: The study was conducted in the Department of Hepatobiliary Sciences at King Abdul-Aziz Medical City, King Fahad National Guard Hospital, Riyadh, Kingdom of Saudi Arabia from March 1997 to January 2000. Sixty-two patients (33 males and 29 females) aged > or =18 with chronic hepatitis C not treated previously were tested for HCV genotype and randomly assigned to receive interferon (IFN) alfa 2b 3 million units 3 times per week alone or in combination with ribavirin 1000-1200 mg orally per day for 48 weeks. All patients were monitored for safety and efficacy of the therapy at 4 week intervals during treatment and followed up for at least 24 weeks after completion of treatment. The primary end point was loss of detectable HCV-RNA 24 weeks after treatment completion, defined as sustained virological response (SVR). RESULTS: Hepatitis C virus genotype 4 was seen among (64.5%) HCV Saudi patients. Hepatitis C virus genotype 1 was the next most common (30.6%). A SVR of 42.8% (9 out of 21) was seen in HCV genotype 4 and 40% (4 out of 10) among other HCV genotypes with combination therapy of IFN and ribavirin (p>0.1). With IFN alone the sustained response rate was 15.7% for genotype 4 and 16.6% for other genotypes mainly genotype 1 (p>0.1). CONCLUSION: We concluded that HCV genotype 4 is the most prevalent genotype among HCV infected Saudi patients. Genotype 1 was the next most common while genotypes 2, 3 and 5 were least prevalent. There is no statistically significant difference in response rate of patients with HCV genotype 4 to either IFN alone or IFN plus ribavirin when compared with genotype 1 of HCV.

Adult↗
PubMed2004

Hepatitis B virus genotypes and spontaneous hepatitis B e antigen seroconversion in Taiwanese hepatitis B carriers.

Hepatitis B virus (HBV) is classified into eight genotypes (A-H), and genotype C is associated with more aggressive liver disease compared to genotype B. However, the mechanisms responsible for the clinical differences remain unclear. To test whether genotype C patients had with lower rates of spontaneous hepatitis B ge antigen (HBeAg) seroconversion than genotype B patients, stored serum samples from 146 Taiwanese adult HBeAg-positive hepatitis B carriers followed-up for a mean of 52 months (range, 12-120 months) were tested for HBV genotype by a molecular method. Genotype C patients were significantly older than genotype B patients (mean age, 37 +/- 12 vs. 29 +/- 10 years, P < 0.001). During the follow-up period, genotype C patients had a significantly lower rate of spontaneous HBeAg seroconversion than genotype B patients (27 vs. 47%, P < 0.025). Spontaneous HBeAg seroconversion occurred one decade later in genotype C patients compared with genotype B patients. Multivariate analyses identified age < or =35 years (odds ratio: 2.08; 95% confidence interval [CI], 1.07-4.0; P < 0.05), high baseline serum alanine aminotransferase level (odds ratio: 2.34; 95%CI, 1.39-4.09; P < 0.005), and HBV genotype B (odds ratio: 1.94; 95%CI, 1.03-3.63; P < 0.05) as independent factors associated with spontaneous HBeAg seroconversion. In conclusion, genotype C patients, compared to genotype B patients, have a delayed HBeAg seroconversion in the immune clearance phase of chronic HBV infection, which may contribute to a more progressive liver disease and more refractory to antiviral therapy.

Adolescent↗
PubMed2001

Molecular characterization of hepatitis C virus genotype 2a from the entire sequences of four isolates.

Genotype 2a hepatitis C virus (HCV) has different characteristics from genotype 1b, such as responsiveness to interferon therapy. Such type-specific characteristics appear to be due to differences in the HCV genome sequence. The complete sequences of genotype 2a HCV genome isolated from four patients with chronic hepatitis C were determined, and nucleotide and deduced amino acid sequences were compared within genotype 2a, as well as between genotype 2a and 1b. Whereas the amino acid sequence similarity of the core region was highest within genotype 1b, the NS3 and NS4B regions of exhibited greater similarity than the core region in genotype 2a. The serine protease and helicase motifs in the NS3 region were well conserved in genotype 2a to the same degree as in genotype 1b. However, the putative secondary structure of 2a isolates was significantly different from that of the 1b isolates. Analysis of amino acid similarity between genotypes 2a and 1b revealed the lowest degree of similarity in the E1 region, followed by the NS2 and NS5A region. Sequences of genotype 2a in the interferon-sensitivity determining region (ISDR) located in the NS5A region had a deletion of four amino acids compared with that of genotype 1b. When the ISDR of the genotype 2a was aligned for maximal similarity, it exhibited similarity of only 52.5-55.0% when compared with that of HCV-J, which belongs to genotype 1b. These findings for the entire sequences of genotype 2a isolates will contribute to virological studies of HCV.

Amino Acid Sequence↗
PubMed2005

Increased hepatocarcinogenic potential of hepatitis B virus genotype A in Bantu-speaking sub-saharan Africans.

Genotypes A, D, and E of the hepatitis B virus (HBV) circulate in southern Africa, with genotype A predominating. Their hepatocarcinogenic potential in Bantu-speaking sub-saharan Africans is, however, unknown. Using a case/control format, we investigated the hepatocarcinogenic potential of these genotypes and subgenotype A1 of genotype A, which accounts for the great majority of genotype A isolates. HBV isolates from 111 unselected Bantu-speaking sub-saharan Africans with hepatocellular carcinoma (HCC) and 111 matched asymptomatic chronic carriers, serving as controls, were genotyped using the method of [Lindh et al. (1997): J Infect Dis 175:1285-1293]. Subgenotypes of genotype A were determined using an in-house restriction fragment length polymorphism assay. Genotype A was present in 96 (86.5%) of patients with HCC and 76 (68.5%) of the carriers, giving a 4.5-fold (95% confidence limits: 1.86, 10.90) increased risk of HCC in carriers infected with genotype A compared with those infected with non-A genotypes. HCC patients infected with genotype A were significantly younger than those infected with non-A genotypes (P = 0.02). The distributions between these two groups according to sex, geographic background, and tribe were not significantly different. Subgenotype A1 was present in all of the 77 cancer patients and 69 of 70 carriers analyzed, yielding a relative risk of 4.21 (95% confidence limits: 1.73,10.23) of HCC in those infected with subgenotype A1 compared with those infected with non-A genotypes. Genotype A has a greater hepatocarcinogenic potential than non-A genotypes in Bantu-speaking sub-saharan Africans and this is entirely attributable to subgenotype A1.

Adolescent↗