Cryptic HBV Replicative Activity Is Frequently Revealed in Anti-HBc-Positive/HBsAg-Negative Patients with HIV Infection by Highly Sensitive Molecular Assays, and Can Be Predicted by Integrating Classical and Novel Serological HBV Markers

Association between markers of hepatitis B virus infection and risk of virological rebound in people with HIV receiving antiretroviral therapy

OBJECTIVES

The aim of this analysis was to investigate the impact of hepatitis B virus (HBV) coinfection on the risk of HIV viral rebound (VR) after achieving suppression for the first time following initiation of antiretroviral therapy (ART) in the real-world setting.

DESIGN

Patients living with HIV (PLWH) who were enrolled in the ICONA Foundation Study cohort and achieved viral suppression ≤50 copies/mL for the first time after starting ART were prospectively evaluated and divided in three exposure groups according to serology test results: (a) HIV-monoinfected; (b) HIV-positive/HBcAb-positive/HBsAg-negative; (c) HIV-positive/HBsAg-positive. The occurrence of VR, defined as two consecutive HIV-RNA values >50 copies/mL after achieving viral suppression for the first time (baseline), was investigated.

METHODS

Standard survival analysis by means of Kaplan-Meier curves and Cox regression analysis with the serology exposure fitted as a time-fixed covariate measured at baseline was employed after controlling for key confounding factors.

RESULTS

Of a total of 5657 patients included, 4090 (72%) were HIV-monoinfected, 1342 (23.7%)were HBcAb-positive, and 225 (3.9%) were HbsAg-positive coinfected. Overall, 654 (11.5%) PLWH experienced VR > 50 copies/mL during follow-up. After controlling for all sources of measured confounding, coinfected PLWH showed an increased risk of experiencing VR compared with those who were HIV-monoinfected. In particular, the strongest associations were seen for the HIV/HBsAg-positive participants [adjusted hazard ratio (aHR) = 1.56, 95% confidence interval (CI): 1.03-2.38, p = 0.037] but an excess of risk was also seen in those who were HIV-positive/HBcAb-positive/HBsAg-negative (aHR = 1.25, 95% CI: 1.00-1.55, p = 0.047).

CONCLUSIONS

Coinfection with HBV seems to have an impact on the probability of maintaining HIV viral suppression achieved for the first time after ART initiation. Of note, even PLWH positive for HBcAb, a marker of inactive HBV infection, appeared to be at higher risk of VR compared with those who were HIV-monoinfected and their HIV-RNA should be carefully monitored.

HBcAb Positivity as a Risk Factor for Missing HIV RNA Undetectability after the 3TC+DTG Switch

Hepatitis B Core antibody (HBcAb) positivity is the surrogate marker of hepatitis B occult infection. This condition is not a contraindication for switching to two-drug (2DR) antiretroviral therapy; however, the removal of tenofovir may contribute to poor control of HBV replication. A multicentre retrospective cohort study investigated the impact of HBcAb positivity on HIV control in patients switching to a 2DR with Lamivudine and Dolutegravir (3TC-DTG). In this study, a comparison analysis was conducted between HBcAb-positive and -negative PLWH regarding HIV-RNA suppression, considering: (1): Target Not Detected (TND) < 20 cp/mL; (2) Target Detected (TD) < 20 cp/mL; and (3) Detectable > 20 cp/mL and <50 cp/mL and >50 copies/mL. A total of 267 patients on 2DR with 3TC-DTG were included. In comparison to HBcAb-negative, HBcAb-positive patients were older (45 years [35-54]) and had a lower CD4+ nadir (248 vs. 349 cells/mmc, p = 0.007). No difference in the maintenance of virological suppression was present in the two groups of patients before the switch. Although no patient had an HIV-RNA > 20 cp/mL after the switch, significantly fewer HBcAb-positive compared with -negative subjects resulted in TND at 12, 24, and 36 months after the switch: 52 (69.3%) versus 164 (85.4%), p = 0.004, 50 [72.5%] versus 143 [89.9%], p = 0.001, and 30 [66.7%] versus 90 [92.8%], p = 0.001, respectively. HBcAb positivity is associated with an increased risk of suboptimal HIV suppression during the 36 months after 3TC/DTG simplification. This finding reinforces the relevance of the OBI condition in PLWH and raises the issue of careful virological monitoring of such cases.

Clinical Utility of Quantitative HBV Core Antibodies for Solving Diagnostic Dilemmas

The present-day management of hepatitis B virus (HBV) infection relies on constant and appropriate monitoring of viral activity, disease progression and treatment response. Traditional HBV infection biomarkers have many limitations in predicting clinical outcomes or therapy success. Quantitation of HBV core antibodies (qAnti-HBc) is a new non-invasive biomarker that can be used in solving multiple diagnostic problems. It was shown to correlate well with infection phases, level of hepatic inflammation and fibrosis, exacerbations during chronic infection and presence of occult infection. Further, the level of qAnti-HBc was recognised as predictive of spontaneous or therapy-induced HBeAg and HBsAg seroclearance, relapse after therapy discontinuation, re-infection after liver transplantation and viral reactivation upon immunosuppression. However, qAnti-HBc cannot be relied upon as a single diagnostic test to solve all dilemmas, and its diagnostic and prognostic power can be much improved when combined with other diagnostic biomarkers (HBV DNA, HBeAg, qHBsAg and anti-HBs antibodies). The availability of commercial qAnti-HBc diagnostic kits still needs to be improved. The comparison of results from different studies and definitions of universal cut-off values continue to be hindered because many methods are only semi-quantitative. The clinical utility of qAnti-HBc and the methods used for its measurement are the focus of this review.

Highly Sensitive HBsAg, Anti-HBc and Anti HBsAg Titres in Early Diagnosis of HBV Reactivation in Anti-HBc-Positive Onco-Haematological Patients

The role of novel HBV markers in predicting Hepatitis B virus reactivation (HBV-R) in HBsAg-negative/anti-HBc-positive oncohaematological patients was examined. One hundred and seven HBsAg-negative/anti-HBc-positive oncohaematological patients, receiving anti-HBV prophylaxis for >18 months, were included. At baseline, all patients had undetectable HBV DNA, and 67.3% were anti-HBs positive. HBV-R occurred in 17 (15.9%) patients: 6 during and 11 after the prophylaxis period. At HBV-R, the median (IQR) HBV-DNA was 44 (27–40509) IU/mL, and the alanine aminotransferase upper limit of normal (ULN) was 44% (median (IQR): 81 (49–541) U/L). An anti-HBc > 3 cut-off index (COI) plus anti-HBs persistently/declining to <50 mIU/mL was predictive for HBV-R (OR (95% CI): 9.1 (2.7–30.2); 63% of patients with vs. 15% without this combination experienced HBV-R (p < 0.001)). The detection of highly sensitive (HS) HBsAg and/or HBV-DNA confirmed at >2 time points, also predicts HBV-R (OR (95% CI): 13.8 (3.6–52.6); 50% of positive vs. 7% of negative patients to these markers experienced HBV-R (p = 0.001)). HS-HBs and anti-HBc titration proved to be useful early markers of HBV-R. The use of these markers demonstrated that HBV-R frequently occurs in oncohaematological patients with signs of resolved HBV infection, raising issues of proper HBV-R monitoring.

Significance of anti-HBc serological status in primary immune thrombocytopenia

The association of previous hepatitis B virus (HBV) exposure [hepatitis B surface antigen (HBsAg) negative, hepatitis B core antibody (anti-HBc/HBcAb) positive] with disease severity and decision on treatment option in primary immune thrombocytopenia (ITP) patients remains unclear. Data from 725 patients diagnosed with ITP were analyzed to elucidate the association between anti-HBc serological status and disease severity. Data from a published prospective study [high-dose dexamethasone (HD-DXM), HD-DXM plus recombinant human thrombopoietin, NCT01734044] and two retrospective studies (standard-dose and low-dose rituximab) were rearranged to evaluate the impact of anti-HBc serological status on the response and outcome to ITP-specific treatments and the risk of HBV reactivation related to these treatments. The prevalence of HBsAg^- HBcAb⁺ and HBsAg^- HBcAb^- in ITP patients was 51·03% and 48·97% respectively. Compared to the HBsAg^- HBcAb^- group, patients in the HBsAg^- HBcAb⁺ group had lower platelet count, higher bleeding score, and longer hospitalization (P = 0·002, 0·033, and 0·008 respectively). Moreover, the initial complete response rate of HBsAg^- HBcAb⁺ patients was lower than that of HBsAg^- HBcAb^- patients (45·2% vs 59·8%, P = 0·027). In conclusion, previous HBV exposure was correlated with disease severity and hospitalization in ITP patients. Anti-HBc positivity may be considered as a predictor for poor response to ITP-specific treatments.

Hepatitis B, Hepatitis C, tuberculosis and sexually-transmitted infections among HIV positive patients in Kazakhstan

In contrast with global trends, HIV prevalence in Kazakhstan and other Central Asian countries has been rising in recent years. In this study, we analyzed hepatitis B (HBV), hepatitis C (HCV), tuberculosis (TB) and sexually-transmitted (STI) co-infections among 500 HIV positive study participants recruited from all regions of Kazakhstan. Among our study participants, 27%, 8%, 2%, and 5% were coinfected with, respectively, HCV, TB, HBV, and STI. A considerable proportion of the study participants was also found with triple or quadruple infections of HCV/TB (12%), TB/STI (0.8%), HCV/STI (2%), HCV/HBV (1%), HBV/TB (0.4%), HBV/STI (0.2%), HBV/HCV/TB (0.4%), HBV/HCV/STI (0.2%), or HCV/TB/STI (0.2%). Strong associations were found of certain age groups, duration of HIV infection, and practices of injection drug use and sexual contact with PLWH, with co-infections of HIV/HCV and HIV/TB. The odds of having death was 4.07 times higher with TB/HIV as compared to other co-infections. Co-occurrence of HIV with HCV, HBV, and TB infections among participants of this study highlights the necessity of regular screening for HCV infection among HIV infected patients, together with implementation of vigilant vaccination protocols against HBV and TB. Additionally, persons who inject drugs especially need to be focused for harm reduction efforts that include opiate substitution therapy, needle or syringe exchange programs, regular screening, and increased availability of ART and direct acting antivirals.

HBcAb Positivity Is a Risk Factor for an Increased Detectability of HIV RNA after Switching to a Two-Drug Regimen Lamivudine-Based (2DR-3TC-Based) Treatment: Analysis of a Multicenter Italian Cohort

The aim of this study was to evaluate whether the presence of anti-hepatitis B (HBV) c antibodies (HBcAb positivity) could influence the control of Human Immunodeficiency Virus (HIV) viremia in patients living with HIV (PLWH) who switch a to two-drug antiretroviral therapy (2DR) containing lamivudine (3TC) (2DR-3TC). A retrospective observational multicenter study was conducted on 166 PLWH switching to the 2DR-3TC-based regimen: 58 HBcAb-positive and 108 HBcAb-negative patients. The HBcAb-positive PLWH group demonstrated a significantly higher percentage of subjects with very low-level viremia at all time points after switching (6th month: <31% vs. 17.6%, p = 0.047; 12th month 34% vs. 27.5%, p = 0.001; 24th month 37% vs. 34.2, p = 0.003 of the HBcAb-positive and HBcAb-negative groups, respectively) and a higher percentage of subjects with detectable HIV RNA greater than 20 copies/mL 12 and 24 months after switching (12 months 32% vs. 11%, p = 0.001; 24 months 37% vs. 13.9%, p = 0.003 of the HBcAb-positive and HBcAb-negative groups, respectively). Logistic regression analysis showed that an increase in age of ten years (OR 2.48 (95% CI 1.58–3.89), p < 0.0001) and the presence of HBcAb positivity (OR 2.7 (5% CI 1.05–6.9), p = 0.038) increased the risk of detectability of HIV RNA by nearly three-fold after switching to 2DR-3TC.