Peculiarity of Clinical Course of Childhood Hepatitis C Depending on the Viral Genotype

Abstract

Hepatitis C is a serious problem for Russian Federation. Determination of HCV genotype/subtype is needed for epidemic control, development of antiviral drugs, vaccines, and planning expenditures for treatment. The aims of the study were to establish the structure of HCV genotype in infected children in Moscow region and to analyse the features of hepatitis, induced by different viral subtypes. Methods. HCV RNA was detected by RT-PCA with a high sensitivity (15 ME/ml). Viral genotyping and determination of intergenotype recombination were done by sequencing HCV genome regions of 5'-NTR-core and NS5B. HCV nucleocapsid antigen (core-Ag) revealing and quantifing in serum were done by ELISA and immunochemioluminesent method. Antibodies to individual structural and nonstructural HCV antigens were determined by ELISA. The level of specific antibodies was determined by titration. Routes of HCV transmission was established by a survey by of parents using the standard protocol. Results. The average age of 63 infected children was 11.3 ± 0.78 years. The main HCV subtypes were 3a (46.03%), 1b (33.3%), and 1a (11.6%). Three children (4.8%) showed intergenotype recombinant RF_2k/1b. Most children have been infected by vertical transmission (69.8%). In order to identify significant differences in hepatitis features we analyzed three groups of children with chronic hepatitis C: the first group - 10 children with subtype 3a, the second group - 10 patients with subtype 1b, and the third group - 7 participants with subtype 1a. There are no significant differences in the symptoms, syndromes and biochemical parameters in these groups. The value of viral load and core-Ag were significantly higher in patients with subtype 3a (P < 0.1) than in the groups of children infected with subtype 1a or 1b. Anti-HCV IgM, anti-NS4 IgG and anti-NS5 IgG in patients, chronically infected by subtype 3a, were detected less often (p < 0.05) than in the other groups. conclusion. The proportion of HCV subtype 3a has increased in infected children in the Moscow region. Intergenotype recombinant RF_2k/1b was firstly detected in children. Patients, infected by HCV subtype 3a, displayed higher viral load and often lack of anti-HCV IgM, anti-NS4ab IgG, and anti-NS5a IgG. Children, infected by HCV subtypes 1a, 1b, and 3a, have no significant differences in the symptoms, syndromes and liver biochemical parameters.