Background: Distribution, clinical characteristics and clinical response to antiviral treatment vary among hepatitis B viral (HBV) genotypes. This study aimed to describe the prevalence, demography and clinical characteristics of the HBV genotypes among chronic hepatitis B patients who were not on treatment in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). Methods & Materials: A total of 1200 plasma samples received by the Molecular Biology Laboratory from 2015 to 2017 for HBV viral load were screened for volume adequacy and viral load of at least 1000 IU/mL. Records were traced to include cases not on any antiviral therapy, cases without co-infection with other hepatitis virus or HIV, and cases without other causes of liver disease. Real-time polymerase chain reaction with 3 steps melting curve analysis was done. Sequencing was done in a private laboratory for 7 samples with undifferentiated genotypes using the platform of ABI 3730 XL (Applied Biosystems). The association among genotypes, demographic and clinical characteristic data (viral load, HBeAg, AntiHBe, ALT, AFP, cirrhosis/HCC) were analysed. Results: Eighty samples (n=80) were successfully genotyped. Of these, 73% (n=59) were genotype B, 20% genotype C (n=16) and 2.5% genotype A (n=2). One sample which constituted 1.3% (n=1) each for genotype D, mixed genotype A+B and mixed genotype B+C. Sixty percent were female (48/80) and mean age was 49 years. Chinese ethnic group recorded the highest cases (78.8%), followed by Malays (17.5%). Majority of the study population (85%) had no cirrhosis by ultrasonography. Normal level of AFP and ALT were predominant (median AFP: 2.46 μg/mL; median ALT: 26 U/L). Anti-Hbe reactivity was significantly higher in those with genotype B than C with normal ultrasound findings (p = 0.035). Individuals infected by genotype A and mixed genotype B+C showed more benign clinical characteristics while genotype B, C, and mixed genotype A+B were more aggressive although not statistically significant. Genotype B was also the most prevalent among the subjects with advanced liver disease in 4 out of 6 subjects (66.7%). Conclusion: Genotypes B and C were most prevalent among chronic hepatitis B patients who were not on treatment in UKMMC. Genotype B was also most prevalent among subjects with advanced liver disease.
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