The Comparison Of HBV Genotying Methods And The Relationship Between HBV Genotype And Clinical Significance

Objective :To compare the HBV genotyping method of direct sequencing of HBV DNA S gene with PCR microplate hybridization-ELISA technique, and to study the relationship between HBV genotypes and clinical outcome . Methods: The HBV genotype of 43 patients with HBV infection was determined by using of PCR microplate hybridization-ELISA technique and direct sequencing of HBV DNA S gene ,and the two HBV genotyping method were compared. Serum samples from 226 HBV infection including 39 asymptomatic HBV carriers(AsC), 14 patients with acute hepatitis B(AHB), 139 patients with chronic chronic hepatitis B(CHB), 23 patients with liver cirrhosis(LC), 11 patients with hepatocellular carcinoma(HCC) were collected and the HBV genotype were determined using of PCR microplate hybridization-ELISA technique. 56 patients with chronic hepatitis B undergoing lamivudine (100mg/day) treatment for 48 weeks,49 patients with chronic hepatitis B were given α-Interferon ( 3 MU/time ,every other day ) therapy for 48 weeks. The serological ,biochemical and virological symbols were measured before,during and after treatment in all patients.Results: The study showed that 39 of 43 sera samples (90.7%) could be correctly identified by PCR microplate hybridization-ELISA technique, and 42 of 43 sera samples (97.7%) could be correctly identified by direct sequencing of HBV DNA S gene . 209 of 226 sera samples (92.5%) could be correctly identified by PCR microplate hybridization-ELISA technique.Among 226 sera, 41(18.1%) were genotype B, 174 (77.0 % ) were genotype C,7 (3.1%) were mixed B and C, and the genotype of 4 patients (1.8%) could not be determined by using directsequencing of HBV DNA S gene and PCR microplate hybridization-ELISA technique.The percentage of genotypes B and C in AsC,AHB,CHB,LC and HCC patients were significantly different^2 = 9.999 , P = 0.040).Compared with genotype B, Patients with genotype C infection tend to have a higher frequency of HBeAg positivity and serume HBV DNA levels than those with genotype B infection (P=0.026,0.043,respectively) . .In a study of 56 patients with chronic hepatitis B treated with lamivudine for 12 months ,no significant difference in viral load reduction ,HBeAg loss or HBeAg seroconversion between patients with genotype B and C. In another study of 49 HBeAg-positive patients chronic hepatitis B treated with interferonfor 12 months, the rate of response to a-Interferon was significantly higher in patients with genotype B compared with those with genotype C. Conclusions:1. The HBV genotyping method of PCR microplate hybridization-ELISA technique is a very sensitive technique, it was proved to be sensitive andspecificity as well as S gene direct sequencing, it is a useful method for large-scale clinical or epidemiologic studies.2. This study suggests that the dominant genotype of HBV in Tianjin was type C,then was type B,type mixed B+C were rare,A,D,E,F,G and H genotypes were not found.3. The study of the relationship between HBV genotype and outcome of infection hepatitis B virus demonstrate that genotype C is associated with more advanced liver disease than genotype B .Patients with genotype C infection tend to have a higher frequency of HBeAg positivity and serume HBV DNA levels than those with genotype B infection.3. Our study show that 56 chronic hepatitis B patients treated with lamivudine for 12 months, no significant difference in viral load reduction or HBeAg...