Data concerning the occurrence of particular HCV types and subtypes in Poland are incomplete and refer mainly to adult patients. The aim of this work was to analyse HCV genotypes in children and young adults with chronic hepatitis. The study was conducted on 54 patients (27 boys and 27 girls) aged 3-20 years, suffering from chronic hepatitis C diagnosed on the basis of serological investigations (over 6-month presence of anti HCV-test UBI, LIATEK and HCV-RNA with the use of RT-PCR method) as well as histopathological evaluation of liver bioptates (according to modified Scheuer classification). HCV genotypes were investigated with the use of Line Probe Assay (INNO - Lipa HCV, Innogenetics) and systematised according to Simmonds classification. Analysis of the frequency of certain HCV genotypes revealed the presence of 1b subtype in 29 patients (53.7%), 1a subtype - in 9 (16.7%), 1 - in 1 (1.8%), 3a - in 3 (5.6%) and 4 - in 12 (22.2%) patients. Mean AlAT activity was 89.6 U/l in subjects with 1a genotype, 68 U/l - in those with 1b, 64 U/L - in patients with genotype 1.43 U/l - in patients with genotype 3a, and 78 U/l - in those with genotype 4. In histopathological picture, trace or slight lesions prevailed, while inflammatory activity of moderate intensification was observed in 14 patients (28%) with various HCV genotypes in a similar percentage of cases. No features of fibrosis were found in the majority of patients, irrespective of HCV type. Type 1 is a dominant genotype in the population of children and young adults with chronic hepatitis C, while clinical picture and the advancement of histopathological lesions in the liver are similar in patients with different genotypes.

Keywords: children and young adults, chronic hepatitis C, HCV genotype