INNO-LiPA HBV genotyping is highly consistent with direct sequencing and sensitive in detecting B/C mixed genotype infection in Chinese chronic hepatitis B patients and asymptomatic HBV carriers

Background: Different HBV genotypes have effect on the progression and outcome of chronic hepatitis B (CHB) and on the response to antiviral therapy. Accurate and sensitive genotyping methods are needed in clinical practice.

Methods: In this multicenter retrospective study, 504 HBV DNA positive serum or plasma samples of CHB patients or asymptomatic carriers were genotyped by INNO-LiPA HBV genotyping and direct sequencing. A part of the consistent and discrepant results were confirmed by clonal sequencing.

Results: Except two samples with indeterminate results by INNO-LiPA, 463 had the same genotype results by INNO-LiPA and direct sequencing with a concordance of 92.23% (463/502). However 24 had completely inconsistent results by the two methods, seven of which were confirmed by clonal sequencing as the same genotype as by direct sequencing. Fifteen samples were determined as B/C mixed genotypes by INNO-LiPA but singe B or C genotype by direct sequencing, five of which were confirmed by clonal sequencing as B/C mixed infection. Further studies showed INNO-LiPA could detect 6% of genotype B and genotype C among mixed genotype samples at HBV DNA ≥3×10(3) IU/ml.

Conclusions: INNO-LiPA is accurate and sensitive in detecting B, C, D and B/C mixed genotype infection in Chinese CHB patients and asymptomatic carriers.