Natural evolution of hepatitis C virus infection in hemodialysis Tunisian patients and CTLA-4 SNP's

Hepatitis C in Tunisia from 1991 to 2019: A systematic review

BACKGROUND

Hepatitis C virus (HCV) is one of the leading causes of chronic liver disease and liver cancer related deaths in Tunisia.

AIM

Perform a systematic review on viral hepatitis C in Tunisia between 1991 and 2019.

METHODS

A global search of HCV-specific documentation in Tunisia (1991-2019) in bibliographic data search sites.

RESULTS

Tunisia is a low endemic country for hepatitis C with a prevalence that not exceed 1% in the general population. Several studies have focused on populations at risk of HCV contamination such as hemodialysis and polytransfused patients. The prevalence of hepatitis C is higher in these groups. In relatively small series, a clear predominance of genotype 1 and subtype 1b has been reported in Tunisia with a lower co-circulation of the other genotypes. Several polymorphisms of cytokine and chemokine genes can influence the clearance or persistence of HCV infection. Tunisian studies have focused on the efficacy of conventional dual therapy (pegylated IFN + ribavirin) by analyzing the predictive factors linked to SVR and mutations associated with resistance to viral inhibitors. No publication has discussed the effectiveness of new direct-acting antivirals in Tunisia.

CONCLUSION

This review of the literature provides an update on the status of hepatitis C in Tunisia and reveals a lack of investigations on new direct-acting antivirals.

Focus on hepatitis C virus genotype distribution in Tunisia prior to elimination: a 16-year retrospective study

With the introduction of direct-acting antiviral treatment (DAA), Tunisia has committed to achieving the international goal of eliminating viral hepatitis. Because the specific DAA prescribed depends on viral genotype, viral genotyping remains of great importance. The aim of the present study was to outline the trends in the distribution of HCV genotypes from 2002 to 2017 in the Tunisian general population in order to guide authorities towards the most appropriate therapeutic strategies for preventing HCV infection. A total of 2532 blood samples were collected over a 16-year period and from all regions of Tunisia. Genotyping showed that genotype 1 (subtype 1b) was the most prevalent genotype in the country (n = 2012; 79.5%), followed by genotype 2 (n = 339; 13.3%). Genotypes 3, 4 and 5 were detected in 4.8%, 2.2% and 0.1% of the country's population, respectively. Mixed infections with different HCV genotypes were detected in 0.1% of the population (one case each of genotypes 1b + 4, 1b + 2 and 2 + 4). Interestingly, a significant increase in genotypes 2, 3 and 4 was observed over time (p = 0.03). Sixteen different subtypes were detected over the study period, most of which were subtypes of genotype 2, and some of these subtypes appeared to be new. Patients infected with genotypes 1a, 3 and 4 were significantly younger than those infected with genotypes 1b and 2 (p < 0.01). Furthermore, genotypes 1b and 2 were detected more often in women than men, while genotypes 1a and 3 were detected mostly in men (P < 0.01). Our study confirms a large predominance of genotype1/subtype1b in Tunisia and shows a significant increase in the prevalence of other genotypes over time. These findings reinforce the need for an additional HCV genotype survey to improve the design of treatment strategies in Tunisia.

[Association between CTLA-4 gene polymorphism and Henoch-Schönlein purpura in children]

OBJECTIVE

To investigate the association between CTLA-4 gene polymorphism and Henoch-Schönlein purpura (HSP) in children.

METHODS

Sixty children who were diagnosed with HSP were enrolled as the case group, consisting of 33 males and 27 females. Thirty healthy children were enrolled as the control group. The patients were further divided into HSP nephritis (HSPN) and non-HSPN groups (n=30 each) according to the presence or absence of nephritis. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze the genotype and allele frequencies at +49 and -1722 loci.

RESULTS

AA, AG, and GG genotypes were detected at +49; neither genotype nor allele frequencies showed significant differences between the case and control groups, between the HSPN and non-HSPN groups, and between male and female patients (P>0.05). TT, TC, and CC genotypes were detected at -1722; neither genotype nor allele frequencies showed significant differences between the case and control groups and between male and female patients (P>0.05). There were significant differences in CC genotype frequency and T and C allele frequencies between the HSPN and non-HSPN groups (P<0.05). Combinational analysis of +49 A/G and -1722 T/C showed no significant differences in the genotype frequency between the case and control groups and between male and female patients (P>0.05). GG-CC combination showed a significant difference between the HSPN and non-HSPN groups (P<0.05).

CONCLUSIONS

CTLA-4 +49 A/G polymorphism is not associated with HSP. CC genotype and C allele of CTLA-4 -1722 and the combination of GG at +49 A/G and CC at -1722 T/C may be risk factors for HSPN.