The role of re-infection in determining rates of spontaneous clearance after hepatitis C exposure

Factors Associated with Spontaneous Clearance of Recently Acquired Hepatitis C Virus among HIV-Positive Men in Brazil

INTRODUCTION

The objective of the present study was to describe the clinical and epidemiological aspects of recently acquired hepatitis C virus (HCV) infection and the frequency of its spontaneous clearance in a people living with the human immunodeficiency virus (PLWH) cohort.

METHODS

We reviewed the medical records from all PLWH at the human immunodeficiency virus (HIV) outpatient reference clinic affiliated with the University of São Paulo, Brazil, and identified, by immunoassays and RNA-PCR individuals who acquired HCV infection between January 2015 and December 2017. The factors associated with subsequent spontaneous clearance of the infection in this group were identified and analyzed.

RESULTS

Among 3143 PLWH individuals, 362 (11.5%) were coinfected with HCV. Forty-eight (13.2%) of these subjects first became HCV-positive between January 2015 and December 2017. Spontaneous HCV clearance was documented in 23 individuals (47.9%). The majority of this latter group were male (83.3%), and the median age was 31 years (23-39). The main risk group for HCV acquisition was men who had sex with men (MSM) (89.5%). In a multivariate analysis, only an elevated CD4+ T lymphocyte count at the time of seroconversion was found to be associated with subsequent HCV clearance (p = 0.025).

CONCLUSIONS

In HIV-infected individuals in Sao Paulo, Brazil, most cases of recent HCV transmission were by sexual exposure. In PLWH, particularly in MSM, the individual's CD4+ T lymphocyte count is a determinant of whether an acquired HCV infection will be prolonged or will spontaneously clear.

Spontaneous viral clearance of hepatitis C virus (HCV) infection among people who inject drugs (PWID) and HIV-positive men who have sex with men (HIV+ MSM): a systematic review and meta-analysis

Background

Hepatitis C virus (HCV) infection causes significant morbidity and mortality among people who inject drugs (PWID) and HIV+ men who have sex with men (MSM). Characterizing spontaneous viral clearance of HCV infection among PWID and HIV+ MSM is important for assessing the burden of disease and treatment strategies in these populations.

Methods

Electronic and other searches of medical literature were conducted. Reports were eligible if they presented original data from upper-middle- and high-income countries on laboratory-confirmed HCV infection and spontaneous viral clearance among PWID or HIV+ MSM. Pooled estimates of spontaneous viral clearance were generated using fixed-effect and random-effects models. Meta-regression examined potential predictors related to individual characteristics and research methodology.

Results

The meta-analysis estimated that spontaneous viral clearance occurs in 24.4 % of PWID and 15.4 % of HIV+ MSM. In univariate meta-regression among PWID, male sex and age were significantly associated with spontaneous viral clearance, and in multivariate analysis, male sex and HIV positivity were predictors of spontaneous viral clearance; among HIV+ MSM no variables were found to affect spontaneous viral clearance.

Conclusion

The variability in estimates of spontaneous viral clearance between HIV+ MSM and PWID suggests the impact of HIV co-infection and HCV re-infection. Due to limited data on additional factors that may affect the natural history of HCV, more research is needed to further understand spontaneous viral clearance in these risk groups.

Protocol registration

The protocols for the PWID and HIV+ MSM research were registered with PROSPERO (CRD42014008805; CRD42013006462).

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1807-5) contains supplementary material, which is available to authorized users.

Spontaneous Clearance of the Hepatitis C Virus Among Men Who Have Sex With Men

BACKGROUND

The probability of spontaneous hepatitis C virus (HCV) clearance ranges from 11% to 49%. Our previous cross-sectional study suggests that mode of acquisition explains some of this heterogeneity. We performed this prospective study to determine factors associated with spontaneous HCV clearance among men who have sex with men (MSM).

METHODS

A mixture-cure model was used to evaluate the probability of spontaneous HCV clearance among 101 MSM in the Multicenter AIDS Cohort Study with acute HCV infection between 1984 and 2012.

RESULTS

Spontaneous HCV clearance occurred in 46% of MSM (49% in non-injection drug users [IDUs] and 23% in IDUs). In the multivariable analysis, age <30 years (clearance ratio [CR] = 2.43; 95% confidence interval [CI], 1.53-3.87) and being human immunodeficiency virus (HIV) uninfected (CR = 2.97; 95% CI, 1.98-4.46) were independently associated with spontaneous clearance. Among men aged ≥30 years, being HIV uninfected, not having unprotected anal intercourse, older age, and being on highly active antiretroviral therapy were independently associated with higher clearance. The interferon lambda rs12979860 single nucleotide polymorphism (SNP) was not associated with spontaneous clearance among the 88 MSM who were not active IDUs (CR = 0.74; 95% CI, .46-1.21 for CC vs CT/TT genotype).

CONCLUSIONS

The high probability of spontaneous HCV clearance together with the lack of an association between the rs12979860 SNP and spontaneous clearance among MSM who do not use injection drugs suggests that the immune mechanisms involved with a successful response to acute HCV differ by mode of virus acquisition. Understanding potential mechanistic differences could be important for HCV vaccine development.

Differences in hepatitis C virus prevalence and clearance by mode of acquisition among men who have sex with men

We examined the characteristics associated with hepatitis C virus (HCV) antibody (anti-HCV) prevalence and HCV clearance between injection drug using (IDU) and non-IDU men who have sex with men (MSM). Stored serum and plasma samples were tested for anti-HCV and HCV RNA to determine the HCV status of 6925 MSM at enrolment into the Multicentre AIDS Cohort Study (MACS). Prevalence and clearance ratios were calculated to determine the characteristics associated with HCV prevalence and clearance. Multivariable analyses were performed using Poisson regression methods with robust variance estimation. Anti-HCV prevalence was significantly higher among IDU than among non-IDU MSM (42.9% vs 4.0%), while clearance was significantly lower among IDU MSM (11.5% vs 34.5% among non-IDU MSM). HIV infection, Black race, and older age were independently associated with higher prevalence in both groups, while smoking, transfusion history, and syphilis were significantly associated with prevalence only among non-IDU MSM. The rs12979860-C/C genotype was the only characteristic independently associated with HCV clearance in both groups, but the effects of both rs12979860-C/C genotype [clearance ratio (CR) = 4.16 IDUs vs 1.71 non-IDUs; P = 0.03] and HBsAg positivity (CR = 5.06 IDUs vs 1.62 non-IDUs; P = 0.03) were significantly larger among IDU MSM. HIV infection was independently associated with lower HCV clearance only among non-IDU MSM (CR = 0.59, 95% CI = 0.40-0.87). IDU MSM have higher anti-HCV prevalence and lower HCV clearance than non-IDU MSM. Differences in the factors associated with HCV clearance suggest that the mechanisms driving the response to HCV may differ according to the mode of acquisition.

The ABCs of viral hepatitis that define biomarker signatures of acute viral hepatitis

Viral hepatitis is the leading cause of liver disease worldwide and can be caused by several agents, including hepatitis A (HAV), B (HBV), and C (HCV) virus. We employed multiplexed protein immune assays to identify biomarker signatures of viral hepatitis in order to define unique and common responses for three different acute viral infections of the liver. We performed multianalyte profiling, measuring the concentrations of 182 serum proteins obtained from acute HAV- (18), HBV- (18), and HCV-infected (28) individuals, recruited as part of a hospital-based surveillance program in Cairo, Egypt. Virus-specific biomarker signatures were identified and validation was performed using a unique patient population. A core signature of 46 plasma proteins was commonly modulated in all three infections, as compared to healthy controls. Principle component analysis (PCA) revealed a host response based upon 34 proteins, which could distinguish HCV patients from HAV- and HBV-infected individuals or healthy controls. When HAV and HBV groups were compared directly, 34 differentially expressed serum proteins allowed the separation of these two patient groups. A validation study was performed on an additional 111 patients, confirming the relevance of our initial findings, and defining the 17 analytes that reproducibly segregated the patient populations.

CONCLUSIONS

This combined discovery and biomarker validation approach revealed a previously unrecognized virus-specific induction of host proteins. The identification of hepatitis virus specific signatures provides a foundation for functional studies and the identification of potential correlates of viral clearance.