GENOTYPIC PROFILE AND DYNAMICS OF VIRAL LOAD IN PATIENTS WITH CHRONIC HEPATITIS C DURING STANDARD ANTIVIRAL THERAPY IN THE REPRESENTATIVES OF KAZAKH AND SLAVIC POPULATIONS IN THE REPUBLIC OF KAZAKHSTAN

Objective. To identify the genotypic profile and features of a virologic response to standard antiviral therapy (AVT) in patients with chronic hepatitis C (CHC) who belong to the indigenous and non-indigenous populations of the Republic of Kazakhstan. Subjects and methods. 221 patients aged 18 to 60 years with CHCfrom different regions of Kazakhstan were examined. Of them there were 143 ethnic Kazakh patients and 78 non-indigenous (Slavic) patients. Results. Equal proportions of genotypes 1b and non-1 (genotypes 2 and 3) of hepatitis C virus (HCV) were found among both the indigenous and non-indigenous populations of the Republic of Kazakhstan. With HCV genotype 1b in the Slavic group on AVT, the viral load declined more slowly than in the Kazakh group and was higher at weeks 4, 12, 24, and 36 of AVT. All the patients achieved a virologic response by the end of treatment. A sustained virologic response (SVR) was achieved in 85.0% of the Kazakhs and 71.6% of the Slavs. With HCV genotypes 2 and 3 in both groups on AVT, the viral load significantly decreased just by week 4 of treatment. In the ethnic Kazakh patients, the decrease was considerably higher. By the end of treatment (at week 24), both groups showed a viral load drop to an undetectable level. SVR was achieved in 87.5% of the indigenous patients and in 76.9% of the non-indigenous ones. Conclusion. HCV genotypes 1b and non-1 (genotypes 2 and 3) are detected with virtually equal frequency in patients with HCV in Kazakhstan. Kazakh ethnicity should be considered as a positive predictor of successful AVT in HCV patients.

chronic hepatitis C, virus genotypes, hepatitis C virus RNA, viral load, polymerase chain reaction, antiviral therapy