[Clinical course and outcomes of chronic viral hepatitis D in patients from Republic of Tuva as endemic region].

INTRODUCTION: Hepatitis D (delta, 5) is caused by an RNA virus (hepatitis D virus, HDV) from genus Deltavirus, and is the most severe and difficult to treat disease among both viral hepatitis and infectious diseases in general. The development of HDV infection in the host organism is possible only in the presence of hepatitis B virus (HBV). Coinfection with HBV and HDV is associated with a more rapid progression of chronic viral hepatitis (CVH) to liver cirrhosis (LC) and an unfavorable outcome in comparison with HBV monoinfection. Data on the influence of clinical, biochemical and virological factors on the infectious process in patients with hepatitis D are limited due to the insufficient amount of research on this theme.The study aimed to determine demographic, clinical, biochemical, and virological factors influencing the course and progression of CVH D in patients followed during 10 years, residing in the territory of the Tuva Republic, one of the endemic regions of the Russian Federation. MATERIAL AND METHODS: Changes in clinical and laboratory parameters were analyzed in dynamics in 121 HDV infected patients with a different course of the disease, who were under observation from 2009 to 2019. Three groups of patients were identified: group 1 - 61 patients with disease progression of chronic hepatitis to LC (Child-Pugh class B-C), group 2 - 49 patients with non-progressive chronic hepatitis, and group 3 - 11 patients with slowly progressive LC (class A). Demographic data, the presence of detectable HBV DNA, indicators of the functional state of the liver: alanine aminotransferase (ALT/GPT), aspartate aminotransferase (AST/GOT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), and total bilirubin content were analyzed. The severity of hepatic encephalopathy was assessed by the duration of the numbers connection test (NCT). RESULTS: All patients belonged to the same ethnic group (Tuvinians), were infected with HDV genotype 1 and were positive for HDV RNA throughout the entire follow-up period. There were no significant differences in sex ratio and mean age at the time of inclusion in the study between the groups. In group 1, the average number of years from inclusion in the study to the formation of LC was 3.65 ± 2.3 years, years to the lethal outcome: 4.5 ± 3 years. Significantly higher levels of AST/GOT, ALP, GGT, total bilirubin (TB) and NCT grade were found in group 1 compared to group 2. ALT/GPT levels did not differ significantly in these groups. When comparing groups with disease progression and slowly progressive LC (groups 1 and 3), no significant differences were found in any of the clinical and biochemical parameters. ALT/GPT, GGT, TB and NCT values were significantly higher in patients with slowly progressive LC (group 3) compared to group 2. No differences in AST/GOT and ALP levels were found between these groups. Detectable HBV DNA was significantly more frequent in patients with progressive disease and with chronic viral hepatitis than in patients with slowly progressive LC. There were no significant differences in the frequency of HBV DNA detection in patients from groups 1 and 2. CONCLUSION: The results obtained on a relatively homogeneous cohort demonstrated that age and gender are not the factors influencing the progression of chronic viral hepatitis D to cirrhosis. The lack of detectable HBV DNA is associated with the slow progression of LC. The revealed differences in clinical and biochemical parameters reflect the degree of functional liver damage in chronic viral hepatitis D and HDV-associated cirrhosis.

[Detection of markers of hepatitis B and D virus infection in biological media and dried blood spots.]

The aim of this study was to assess the rates of detection of the major markers of infection with hepatitis B and Delta (D) viruses in serum, saliva and dry blood dots (DBS) as a possible option for serological studies among the population of the endemic region in conditions of limited laboratory resources. For this purpose, paired samples of blood serum and DBS, blood serum and saliva from patients with chronic hepatitis B with Delta agent living in the Republic of Tyva, which is endemic for this disease. HBsAg was detected in 289 (100%) serum samples, in 88/92 (95.7%) saliva samples, in 60/80 (75%) DBS samples, stored three years at room temperature, and in 111/117 (94.9%) DBS stored one year at the same conditions. Anti-HBcore was detected in 209 (100%) serum samples, while in saliva and DBS samples this marker was detected in only 13.04% (12/92) and 19.7% (23/117), respectively. Anti-HDV antibodies in serum were detected in 209 (100%) samples collected from patients in 2017-2018. In saliva and DBS anti-HDV were not detected in any sample. This difference in the detection rates of anti-HBcore and anti-HDV might be accounted for the fact that the HBV core protein is a very strong immunogen, indusing the production of anti-HBcore in high concentrations. Probably, the concentration of anti-HDV is much lower, which explains its absence in saliva and DBS in patients with hepatitis B+D. Samples of biological media (saliva), as well as DBS can serve as an alternative material for the detection of HBsAg in screening and research prevalence studies. Meanwhile, the definition of anti-HDV in such media is not possible due to the false negative results. Due to the high probability of superinfection with HDV in patients with HBV in endemic areas, the detection of HBsAg in alternative media (saliva or DBS) should be followed by testing for anti-HDV in serum samples.

[FAMILIAL CLUSTERS OF HEPATITIS DELTA IN ENDEMIC REGION (REPUBLIC TYVA)].

AIM: Clinical and virological characteristic of hepatitis delta familial clusters in region of Russia that is endemic for this infection (Republic Tuva). MATERIALS AND METHODS: Total 383 patients with HBV/HDV coinfection and their family members (3 generations) were followed. Serum samples for HDV and HBV markers testing were available for 42 patients from 18 families. HBsAg, anti-HBc, HBeAg, anti-HBe and anti-HDV were tested using commercial ELISA tests; HDV RNA and HBV DNA were tested using in house nested PCR tests. RESULTS: 30 family (63 people) clusters were identified, in which close living persons have been infected with HDV and HBV. The biological material for determining of HDV and HBV markers has been available from 18 families (42 people belonging to 1-3 generations (parents and children, husband and wife, brother and sister). The mean age was 35 ± 14 years (10-58 years). Chronic hepatitis (CH) was in 30 (71.4%) patients, liver cirrhosis (LC)--in 10 (23.8%) and HCC was developed in 2 (4.8%) person on the background of long infections. The incidence of HBeAg was 14.3% (6/42), HBV DNA--19% (8/42); HDV RNA--35.7% (15/42). In 2 cases (mother) replication markers of both viruses were found, it contributed to the increased risk of infection in children. So HDV RNA was detected in the blood serum of their daughters (15 and 17), that does not exclude the possibility of vertical transmission. An illustration describes four families. CONCLUSION: The epidemic process of delta infection in the Republic of Tyva is characterized by intrafamilial infection of HBV and HDV.

[Serum lactoferrin levels in children with viral hepatitis A].

Serum lactoferrin levels were studied in 79 healthy children and 80 children with viral hepatitis A in the Republic of Tyva. No statistically significant age- and gender-related differences were found in the healthy children. In viral hepatitis A, the level of the protein was shown to decrease with disease severity and to return to the normal values after 6 months.

[Epidemiological and molecular biological analysis of causes of rise of hepatitis A incidence in Republic of Tuva in 2008].

AIM: Analysis of hepatitis A (HA) incidence in Tyva Republic in 2008 exploiting traditional epidemiological and molecular methods. MATERIALS AND METHODS: Epidemiological analysis of HA cases and contact persons in Erzinsky and Kyzyl regions of Tyva Republic was performed. Class M and G antibodies to HAV were determined in serum samples (n = 28), and HAV RNA--in stool samples (n = 16). Phylogenetic analysis of HAV RNA sequence was performed for VP1/2A region of the HAV genome with length 394 nucleotides. RESULTS: Cases of HA were registered during 3.5 months. Water supply sources did not have deviations from established standards. According to results of interviews, common food factor, which was able to cause the rise of HA incidence, was not determined. Signs of fecal contamination were revealed on environmental objects in preschool institutions and schools that demonstrate the low level of hygienic behaviour. It was shown that all cases of HA are related with different variants of the virus belonged to genotype IA that points to the absence of common source of infection. CONCLUSION: Results of epidemiological and genetic analysis of HAV demonstrate that observed rise in HA incidence in Tyva Republic are connected with phase of seasonal rise of HA incidence, which is characteristic for its perennial dynamics with active realization of contact route of virus transmission.