Clinical significance of genetic diversity of hepatitis A virus

Abstract

Aim: to identify features of the clinical course of hepatitis A (HA) caused by viruses of different subtypes. Patients and methods: In the study there were included 195 patients with hepatitis A (130 males and 65 females) at the age from 15 to 72 years residing in the territories with various manifestations of the epidemic process of HA (Moscow, the Khabarovsk region, the Republic of Sakha (Yakutia), the Republic of Tajikistan and Ukraine). All patients were examined for the presence of Hepatitis A virus (HAV) RNA in blood, with following determination of the genotype of the virus by PCR. Biochemical blood tests (concentration of total and direct bilirubin, ALT activity) were performed from 2 to 9 times depending on the duration of hospital stay and severity of infection. The dynamics of biochemical indices was evaluated in accordance with the period of the disease: the first period -from the 1 st to 10 th day, the second -from 11 th to 20 th day, the third -from the 21 st day and later. Results: A direct moderate correlation (The Spearman correlation coefficient r = 0,3; p = 0,002) between the duration of jaundice and patients ’ age has been revealed. A significant relationship was observed in the group ofpatients with subtype IIIA (r = 0,4; p = 0,003) and was absent in patients with subtype IA. There were no statistically significant differences between the groups of patients with subtypes IA and IIIA, in dependence on the duration of hospitalization, the variant of the course ofprejaundice period, severity of the course disease, duration of the persistent jaundice and symptoms of intoxication. Absolute values and the dynamics of the reduction of total and direct bilirubin, as well as the dynamics of decrease of ALT activity in groups of patients with various subtypes were not differed significantly. Cholestatic forms of HA were observed only in patients with HAV isolates belonging to subtype IIIA. Conclusion: HAV subtype has no effect on the severity of the course of the disease neither major clinical symptoms and laboratory indices in patients from different age groups. A direct correlationship between the duration ofjaundice syndrome and age in patients with subtype IIIA may indicate a trend towards the formation of cholestatic forms of HA in patients with this subtype of the virus in older age groups.