Distribution of Hepatitis B Virus Genotypes and Its Association with Severity of Liver Disease in Patients with Chronic Hepatitis B in Uttar Pradesh, India

Abstract

The present study was designed to investigate the distribution of genotypes and its association with severity of liver disease in patients with Chronic Hepatitis B (CHB) in Uttar Pradesh, India. One hundred five HBsAg positive patients were selected for the study. The DNA was extracted by using pure viral DNA extraction kit. The genotype of Hepatitis B virus (HBV) was identified by using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) method, by using AvaII and DpnII restriction enzyme to see the different patterns of cleavage that would occur at this specific site. Among 105 HBsAg positive chronic liver disease patients 58 patients were positive for HBeAg and 47 samples were HBeAg negative. Genotyping was done successfully in 91 samples. Genotype A was identified in 22% and genotype D in 78% CHB patients. Genotype A showed elevated liver enzymes much more than genotype D. The Child Pugh classification of 20 patients with genotype A was class A (n = 2), B (n = 9), C (n = 9) and of genotype D was class A (n = 13), B (n = 50) and C (n = 8). In conclusion our results showed that Genotype D was the commonest genotype in Uttar Pradesh, whereas genotype A had significantly more elevated ALT/AST levels than genotype D. (P \ 0.05). Child Pugh Grade B was significantly more in patients with genotype D, whereas Child Pugh Grade C was more in genotype A.

Hepatitis B genotyping: The utility for the clinicians

“…These studies have mostly looked at association between the specific HBV genotypes and liver disease severity. A few studies from India reported that genotype D was associated with severe disease compared with genotype A [22,23]. However, another study revealed no difference in clinical and histological severity between genotypes A and D [24].…”

Factors in enhancing blood safety by nucleic acid technology testing for human immunodeficiency virus, hepatitis C virus and hepatitis B virus

“…[ 6 33 38 40 41 43 ] Globally, HBV NAT testing has been gaining acceptance for several reasons including: (a) HBsAg, the commonly diagnosed serology marker, unlike antibody markers, is a transiently expressed viral protein detectable late in infection at 30 days and lasting up to 63 days,[ 10 31 ] (b) mutations in HBsAg result in serology misses,[ 33 ] (c) in certain genotypes such as G, the HBsAg negative WP is substantially prolonged and will be missed by serology tests,[ 37 ] (d) in countries with moderate to high HBV prevalence, positivity for antibody markers will be high resulting in high discard rate, which is not viable for blood supply[ 29 30 44 ] and finally (e) several studies have demonstrated the benefit of high sensitivity ID NAT testing to detect WP and OBI infections. [ 30 ] Factors that necessitate highly sensitive HBV NAT testing in India include (a) relatively high HBsAg positivity of 1.2% in the donor population,[ 8 ] (b) a 10-30% anti-Hepatitis B core (HBc) prevalence,[ 44 ] (c) the major HBV type being Genotype D, followed by A and C,[ 45 46 ] with genotypes D and A documented to remain at low viral load[ 6 34 ] and (d) the additional association of HBV genotype D with high occult HBV infections, which is characterized by fluctuating low viral load. [ 6 35 39 41 42 ]…”