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Detection of Low Copy Number Integrated Viral DNA Formed by In Vitro Hepatitis B Infection
Published on: November 7, 2018
Hepatitis B virus reverse transcriptase mutations in treatment Naïve chronic hepatitis B patients
Bhupesh Singla1, Anuradha Chakraborti, Bal Krishan Sharma
1Departments of Hepatology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
Journal of Medical Virology
|August 7, 2013
Summary
Pre-existing mutations in the hepatitis B virus (HBV) reverse transcriptase (RT) region were found in nearly half of treatment-naïve patients. These HBV RT mutations may reduce susceptibility to antiviral drugs, necessitating genotypic testing before therapy initiation.
Area of Science:
- Hepatology and Virology
- Molecular Biology
- Infectious Diseases
Background:
- Hepatitis B virus (HBV) infection is a global health concern.
- Nucleos(t)ide analogs are key treatments for chronic HBV infection.
- Mutations in the HBV reverse transcriptase (RT) region can confer resistance to these drugs.
Purpose of the Study:
- To detect and analyze pre-existing HBV RT mutations in treatment-naïve patients with chronic hepatitis B.
- To assess the prevalence of specific HBV RT mutations and their potential impact on antiviral susceptibility.
- To provide evidence supporting pre-treatment genotypic testing in chronic hepatitis B patients.
Main Methods:
- Enrollment of 71 treatment-naïve chronic hepatitis B patients.
- HBV RT sequencing using direct bidirectional sequencing of semi-nested PCR products.
- HBV genotyping performed via multiplex PCR.
Main Results:
- HBV Genotype D was predominant (90.1%), followed by C and A.
- Mutations in the HBV RT region were detected in 47.9% of patients.
- The rtH248N mutation was the most frequent (47.1% of mutated samples); primary drug resistance mutations were found in 8.8% of patients.
Conclusions:
- Amino acid substitutions in the HBV RT region are present in a significant proportion of treatment-naïve patients.
- These pre-existing mutations may compromise the efficacy of oral antiviral therapies.
- Genotypic testing prior to initiating antiviral therapy is recommended for optimal drug selection in naïve patients.
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