Genotypes of hepatitis C virus in the Indian sub-continent: A decade-long experience from a tertiary care hospital in South India.

Background: Hepatitis C virus (HCV) is a leading cause of chronic liver disease (CLD) that can progress to cirrhosis and hepatocellular carcinoma. Genotypes of HCV can vary in pathogenicity and can impact on treatment outcome. Objectives: To study the different genotypes among patients with HCV related CLD attending a tertiary care hospital in south India during 2002-2012. Study Design: Study subjects were those referred to clinical virology from the liver clinic. Genotyping was performed using the genotype specifi c core primers in nested polymerase chain reaction (PCR), 5′ non-coding regions based PCR- restriction fragment length polymorphism and NS5B sequencing methods. With the latter method, obtained sequences were compared with published GenBank sequences to determine the genotype. Results: Of the 451 samples tested, HCV genotype 3 was found to be the most predominant (63.85%). Other genotypes detected were genotype 1 (25.72%), genotype 2 (0.002%), genotype 4 (7.5%) and genotype 6 (2.7%). Genotype 3 was the common genotype in patients from Eastern India while genotype 1 and 4 were mainly seen in South Indian patients. Genotype 6 was seen exclusively in patients from North-Eastern India. Two other patients were infected with recombinants of genotype 1 and 2. Conclusions: In this study spanning a decade, HCV genotype 3 and genotype 1 were found to be the predominant genotypes in the Indian sub-continent. Genotype 4 and genotype 6 appeared to show some geographic restriction. A continued monitoring of HCV genotypes is essential for the optimum management of these chronically infected patients. In addition, knowledge of circulating genotypes could impact on future vaccine formulations.

Significance of the hepatitis C virus (HCV) core antigen as an alternative plasma marker of active HCV infection.

PURPOSE: To evaluate the role of core antigen (Ortho trak-C assay) as a marker of active HCV infection in comparison to HCV RNA as detected by reverse transcription polymerase chain reaction (RT-PCR). METHODS: This evaluation was carried out during January 2000 to December 2003 in HCV infected individuals who were treatment naomicronve or were on anti-viral therapy. Additionally, sequential plasma samples from patients on clinical follow-up were included in this study. A total of 167 samples from 61 patients were tested by trak-C and RT-PCR. HCV RNA detection was achieved by a RT-PCR. Trak-C assay results were also compared in a limited proportion of these samples with known HCV viral load and genotype. RESULTS: Of 167 samples tested, 56.9% were RNA positive and 43.1% were RNA negative while 50.3% were trak-C positive and 49.7% were trak-C negative, yielding a sensitivity of 85.3% and a specificity of 95.8% for the trak-C assay (Kappa co-efficient = 0.8). The concentration of HCVcAg and HCV RNA showed significant correlation (n=38, r=0.334, P =0.04). The trak-C assay detected the most prevalent HCV genotypes in India without significant difference (P =0.335). The difference between mean absorbance values of HCV RNA positive samples compared to HCV RNA negative samples in the trak-C assay was highly significant (P < 0.000). Qualitative results of trak-C assay and RT-PCR were comparable in 93% of follow-up samples. CONCLUSIONS: Trak-C assay can be recommended for confirmation of HCV infection and follow-up in laboratories with resource-poor facilities.

Evaluation of an indigenously manufactured rapid immunochromatographic test for detection of HBsAg.

A 'rapid' one step immunochromatographic, visually read, antigen capture assay--the "HEPACARD" (J Mitra & Co. Ltd., New Delhi, India) used for rapid screening of HBsAg was evaluated. Thousand consecutive sera sent to our laboratory for the purpose of HBsAg screening were tested by this device and by a third generation enzyme immunoassay (EIA) (Auszyme Monoclonal, Abbott Laboratories, Chicago, Illinois) or an automated Axsym microparticle enzyme immunoassay (MEIA) (Axsym HBsAg V2, Abbott Laboratories, Abbott Park, Chicago, Illinois, ISA). Hepacard showed a sensitivity of 79% (CU: 57.3-92%) and specificity of 98.9% (CI: 97.9-99.4%) when compared to the findings by the third generation EIA assays. This study suggested that this particular rapid HBsAg test results have to be confirmed by either an EIA or MEIA where the facility exists. The test may be used only in a small hospital setting where the facilities for enzyme immuno assays do not exist.

Infrequent occurrence of silent HBV infection among Indian patients with chronic liver disease.

OBJECTIVE: To investigate the occurrence of silent hepatitis B virus (HBV) infection among patients with chronic liver disease (CLD). METHODS: Plasma samples from 71 CLD patients including 9 HBsAg-positive individuals were tested for HBV DNA by nested polymerase chain reaction (nPCR), and for HBV serum markers, i.e., anti-HBc antibody, HBeAg and anti-HBe antibody. The individuals were also tested for hepatitis C virus (HCV) RNA and anti-HCV antibody. RESULTS: Among 62 HBsAg-negative patients, silent HBV infection was seen in only two (3.2%). Silent HBV infection was not found in any of the 26 patients who had evidence of HCV infection. One HBsAg-positive patient was positive for anti-HCV in the absence of HCV RNA. CONCLUSIONS: There is a low rate of silent HBV infection among patients with CLD in India, where HBV is moderately endemic. Silent HBV infection is not associated with HCV-related CLD, which is in contrast to reports from other HBV-endemic areas in Asia.

Prevalence of enterically transmitted hepatitis viruses in patients attending a tertiary--care hospital in south India.

The prevalance of enterically transmitted hepatitis viruses, namely, hepatitis A virus (HAV) and hepatitis E virus (HEV) were studied in 404 patients with acute hepatitis attending a tertiary-care hospital in south India. Presence of current HAV/HEV infection was ascertained by the demonstration of IgM antibodies. In 381 patients tested for both agents, HAV IgM was present in 51(13.3%) and HEV IgM present in 66(17.3%). There was dual infection in 3 males (0.8%). HEV infection was seen mostly in older children and adults with only 5.5% occurring in children < 12 years of age. HAV infection was commonly seen to occur in < 12 years of age group (52.7%). One hundred and twenty-six patients were from the Vellore region, among whom HAV and/or HEV aetiology was observed in 28.5%. In this region there did not appear to be any correlation between occurrence of acute hepatitis due to these viruses and rainfall or environmental temperature. Acute hepatitis due to enteric hepatitis viruses was seen throughout the year.

Role of molecular techniques in the detection of HBV DNA & HCV RNA among renal transplant recipients in India.

In this study we have investigated the occurrence of hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) infections among 68 renal transplant recipients. Replicative HBV and replicative HCV infections were seen in 12 (17.6%) and 38 (55.9%) patients respectively, the difference was statistically significant (P < 0.001). Among the 38 HCV RNA+ individuals, anti-HCV was present only in 23. Anti-HCV in the absence of HCV RNA was detected in one patient. Anti-HDV antibody was seen in 2 (15.4%) of the 13 HBV infected individuals. Nine (13.2%) of the 68 individuals had replicative dual infection with HBV and HCV. Triple infection (HBV DNA+, HCV RNA+, anti-HDV+) was seen in 2 transplant recipients. There was significantly higher demonstration of replicative HCV (P < 0.001) in transplant recipients having elevated liver enzymes (n = 34) as compared to transplant recipients having normal liver enzyme levels (n = 34). Though not significant, a higher detection rate was also seen with replicative HBV infection and replicative dual infection among transplant recipients with elevated liver enzymes. The higher detection of HCV in renal transplant recipients by molecular techniques, emphasizes the need for HCV RNA testing. Further deliberate attempts to change practices to reduce this problem may also improve graft and patient survival in recipients.