Noninvasive markers of liver fibrosis are highly predictive of liver-related death in a cohort of HCV-infected individuals with and without HIV infection

Higher levels of CRP, D-dimer, IL-6, and hyaluronic acid before initiation of antiretroviral therapy (ART) are associated with increased risk of AIDS or death

BACKGROUND

Substantial morbidity occurs during the first year of antiretroviral therapy (ART) in persons with advanced human immunodeficiency virus (HIV) disease despite HIV suppression. Biomarkers may identify high-risk groups.

METHODS

Pre-ART and 1-month samples from an initial ART trial were evaluated for biomarkers associated with AIDS events or death within 1-12 months. Case patients (n = 63) and control patients (n = 126) were 1:2 matched on baseline CD4 cell count, hepatitis status, and randomization date. All had ≥ 1 log(10) HIV RNA level decrease at 1 month.

RESULTS

Case patients had more frequent prior AIDS events, compared with control patients (P = .004), but similar HIV RNA levels at baseline. Pre-ART and 1-month C-reactive protein (CRP), D-dimer, and interleukin 6 (IL-6) levels and pre-ART hyaluronic acid (HA) levels were associated with new AIDS events or death (P ≤ .01). Patients who experienced immune reconstitution inflammatory syndrome (IRIS) events had higher pre-ART tumor necrosis factor α (TNF-α) and HIV RNA levels and significant 1-month increases in CRP, D-dimer, IL-6, interleukin 8, CXCL10, TNF-α, and interferon-γ levels, compared with patients who experienced non-IRIS events (P ≤ .03). Individuals with baseline CRP and HA levels above the cohort median (>2.1 mg/L and >50.0 ng/mL, respectively) had increased risk of AIDS or death (OR, 4.6 [95% CI, 2.0-10.3]; P < .001) and IRIS (OR, 8.7 [95% CI, 2.2-34.8] P = .002).

CONCLUSIONS

Biomarkers of Inflammation (CRP, IL-6), coagulation (D-dimer), and tissue fibrosis (HA) measured pre-ART and at 1 month are associated with higher risk of AIDS events, IRIS, or death, warranting additional study as risk stratification strategies.

The relation of HLA genotype to hepatitis C viral load and markers of liver fibrosis in HIV-infected and HIV-uninfected women

BACKGROUND

Human leukocyte antigen (HLA) class I and II genotype is associated with clearance of hepatitis C virus (HCV) infection, but little is known regarding its relation with HCV viral load or risk of liver disease in patients with persistent HCV infection.

METHODS

High-resolution HLA class I and II genotyping was conducted in a prospective cohort of 519 human immunodeficiency virus (HIV)-seropositive and 100 HIV-seronegative women with persistent HCV infection. The end points were baseline HCV viral load and 2 noninvasive indexes of liver disease, fibrosis-4 (FIB-4), and the aspartate aminotransferase to platelet ratio index (APRI), measured at baseline and prospectively.

RESULTS

DQB1*0301 was associated with low baseline HCV load (β = -.4; 95% confidence interval [CI], -.6 to -.3; P < .00001), as well as with low odds of FIB-4-defined (odds ratio [OR], .5; 95% CI, .2-.9; P = .02) and APRI-defined liver fibrosis (OR, .5; 95% CI, .3-1.0; P = .06) at baseline and/or during follow-up. Most additional associations with HCV viral load also involved HLA class II alleles. Additional associations with FIB-4 and APRI primarily involved class I alleles, for example, the relation of B*1503 with APRI-defined fibrosis had an OR of 2.0 (95% CI, 1.0-3.7; P = .04).

CONCLUSIONS

HLA genotype may influence HCV viral load and risk of liver disease, including DQB1*0301, which was associated with HCV clearance in prior studies.

Noninvasive tests for fibrosis and liver stiffness predict 5-year outcomes of patients with chronic hepatitis C

BACKGROUND & AIMS

Liver stiffness can be measured noninvasively to assess liver fibrosis in patients with chronic hepatitis C. In patients with chronic liver diseases, level of fibrosis predicts liver-related complications and survival. We evaluated the abilities of liver stiffness, results from noninvasive tests for fibrosis, and liver biopsy analyses to predict overall survival or survival without liver-related death with a 5-year period.

METHODS

In a consecutive cohort of 1457 patients with chronic hepatitis C, we assessed fibrosis and, on the same day, liver stiffness, performed noninvasive tests of fibrosis (FibroTest, the aspartate aminotransferase to platelet ratio index, FIB-4), and analyzed liver biopsy samples. We analyzed data on death, liver-related death, and liver transplantation collected during a 5-year follow-up period.

RESULTS

At 5 years, 77 patients had died (39 liver-related deaths) and 16 patients had undergone liver transplantation. Overall survival was 91.7% and survival without liver-related death was 94.4%. Survival was significantly decreased among patients diagnosed with severe fibrosis, regardless of the noninvasive method of analysis. All methods were able to predict shorter survival times in this large population; liver stiffness and results of FibroTest had higher predictive values. Patient outcomes worsened as liver stiffness and FibroTest values increased. Prognostic values of stiffness (P<.0001) and FibroTest results (P<.0001) remained after they were adjusted for treatment response, patient age, and estimates of necroinflammatory grade.

CONCLUSIONS

Noninvasive tests for liver fibrosis (measurement of liver stiffness or FibroTest) can predict 5-year survival of patients with chronic hepatitis C. These tools might help physicians determine prognosis at earlier stages and discuss specific treatments, such as liver transplantation.

Noninvasive tools to assess liver disease

PURPOSE OF REVIEW

To improve understanding of recent developments in the noninvasive assessment of fibrosis and their potential clinical application to a range of chronic liver diseases.

RECENT FINDINGS

Many noninvasive tests have evolved from their primary validation in chronic hepatitis C virus (HCV) infection to integration into clinical management algorithms for chronic liver disease of varying cause. Recent studies consider the use of these techniques in sequence or in combination, and compare the performance of serum and imaging-based noninvasive techniques to identify patients with significant fibrosis, or those at most risk of clinical sequelae from advanced-stage disease. Methods developed in chronic hepatitis C have now been applied in different chronic liver diseases, including nonalcoholic fatty liver disease, alcoholic liver disease, HIV/HCV co-infection and primary biliary cirrhosis. A number of new management algorithms have been developed to facilitate the integration of noninvasive techniques into clinical practice.

SUMMARY

Noninvasive tools to assess liver diseases continue to evolve. New imaging technologies have been developed. Existing biomarkers and imaging modalities have been better integrated into clinical practice algorithms, and applied to different chronic liver diseases. Noninvasive techniques will likely continue to be refined and play an important role in the future management of patients with chronic liver disease.

Biomarkers of liver fibrosis

Fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. Blood-based biomarkers offer a number of advantages over the traditional standard of fibrosis assessment of liver biopsy, including safety, cost-savings and wide spread accessibility. Current biomarker algorithms include indirect surrogate measures of fibrosis, including aminotransaminases and platelet count, or direct measures of fibrinogenesis or fibrinolysis such as hyaluronic acid and tissue inhibitor of metalloproteinase-1. A number of algorithms have now been validated across a range of chronic liver disease including chronic viral hepatitis, alcoholic and non-alcoholic fatty liver disease. Furthermore, several models have been demonstrated to be dynamic to changes in fibrosis over time and are predictive of liver-related survival and overall survival to a greater degree than liver biopsy. Current limitations of biomarker models include a significant indeterminate range, and a predictive ability that is limited to only a few stages of fibrosis. Utilization of these biomarker models requires knowledge of patient co-morbidities which may produce false positive or negative results in a small proportion of individuals. Furthermore, knowledge of the underlying prevalence of fibrosis in the patient population is required for interpretation of the positive or negative predictive values of a test result. Novel proteins identified by proteomic technology and genetic polymorphisms from genome association studies offer the possibility for further refinement and individualization of biomarker fibrosis models in the future.

Invasive and non-invasive methods for the assessment of fibrosis and disease progression in chronic liver disease

Chronic liver diseases represent a major public health problem, accounting for significant morbidity and mortality worldwide. Their prognosis and management greatly depend on the amount and progression of liver fibrosis with the risk of developing cirrhosis. Liver biopsy, traditionally considered as the reference standard for staging of fibrosis, has been challenged over the past decade by the development of novel non invasive methodologies. These methods rely on two distinct but complementary approaches: i) a 'biological' approach based on the dosage of serum biomarkers of fibrosis; ii) a 'physical' approach based on the measurement of liver stiffness using transient elastography (TE). Non invasive methods have been initially studied and validated in chronic hepatitis C but are now increasingly used in other chronic liver diseases, resulting in a significant decrease in the need for liver biopsy. However, they will likely not completely abolish the need for liver biopsy and they should rather be employed as an integrated system with liver biopsy. This review is aimed at discussing the advantages and inconveniences of non invasive methods in comparison with liver biopsy for the management of patients with chronic liver diseases.

HIV/HCV co-infection: pathogenesis, clinical complications, treatment, and new therapeutic technologies

World-wide, hepatitis C virus (HCV) accounts for approximately 130 million chronic infections, with an overall 3% prevalence. Four to 5 million persons are co-infected with HIV. It is well established that HIV has a negative impact on the natural history of HCV, including a higher rate of viral persistence, increased viral load, and more rapid progression to fibrosis, end-stage liver disease, and death. Whether HCV has a negative impact on HIV disease progression continues to be debated. However, following the introduction of effective combination antiretroviral therapy, the survival of coinfected individuals has significantly improved and HCV-associated diseases have emerged as the most important co-morbidities. In this review, we summarize the newest studies regarding the pathogenesis of HIV/HCV coinfection, including effects of coinfection on HIV disease progression, HCV-associated liver disease, the immune system, kidney and cardiovascular disease, and neurologic status; and effectiveness of current anti-HIV and HCV therapies and proposed new treatment strategies.

Noninvasive assessment of liver fibrosis

Liver biopsy has long been an important tool for assessing the degree of liver fibrosis. Information on the presence and degree of liver fibrosis is useful before making therapeutic decisions or predicting disease outcomes. The need to stage liver fibrosis, however, should decrease as treatment options become more successful (as has occurred with viral hepatitis). In recent years, noninvasive tests have demonstrated a reasonable ability to identify significant fibrosis, cirrhosis in particular, nor is it surprising that liver disease specialists and patients favor a noninvasive approach. However, only those tests with the highest diagnostic accuracy, cost-effectiveness, and availability should be implemented. Apart from their diagnostic accuracy, the potential ability of these tests to predict disease outcomes (a more relevant endpoint) should be compared with that of liver biopsy. Indeed, the use of a standardized system to evaluate the utility of biomarkers would facilitate their implementation in clinical practice.

HCV-specific T cells in HCV/HIV co-infection show elevated frequencies of dual Tim-3/PD-1 expression that correlate with liver disease progression

Co-infection of HCV with HIV has been associated with more rapid progression of HCV-related disease. HCV-specific T-cell immune responses, which are essential for disease control, are attenuated in co-infection with HIV. T-cell exhaustion has recently been implicated in the deficient control of chronic viral infections. In the current study, we investigated the role of programmed death-1 (PD-1) and T-cell immunoglobulin and mucin domain-containing molecule-3 (Tim-3) expression in T-cell exhaustion during HCV/HIV co-infection. We show that in HCV/HIV co-infection, both total and HCV-specific T cells co-express Tim-3 and PD-1 in significantly higher frequencies, compared with HCV mono-infection. Co-expression of these two markers on HCV-specific CD8(+) T cells positively correlated with a clinical parameter of liver disease progression. HCV-specific CD8(+) T cells showed greater frequencies of Tim-3/PD-1 co-expression than HIV-specific CD8(+) T cells, which may indicate a greater degree of exhaustion in the former. Blocking Tim-3 or PD-1 pathways restored both HIV- and HCV-specific CD8(+) T-cell expansion in the blood of co-infected individuals. These data demonstrate that co-expression of Tim-3 and PD-1 may play a significant role in HCV-specific T-cell dysfunction, especially in the setting of HIV co-infection.

Characterization of cross-reactive CD8+ T-cell recognition of HLA-A2-restricted HIV-Gag (SLYNTVATL) and HCV-NS5b (ALYDVVSKL) epitopes in individuals infected with human immunodeficiency and hepatitis C viruses

The immunologic mechanisms underlying the faster progression of hepatitis C virus (HCV) disease in the presence of human immunodeficiency virus (HIV) coinfection are not clearly understood. T-cell cross-reactivity between HCV and influenza virus-specific epitopes has been associated with rapid progression of HCV disease (S. Urbani, B. Amadei, P. Fisicaro, M. Pilli, G. Missale, A. Bertoletti, and C. Ferrari, J. Exp. Med. 201:675-680, 2005). We asked whether T-cell cross-reactivity between HCV and HIV could exist during HCV/HIV coinfection and affect pathogenesis. Our search for amino acid sequence homology between the HCV and HIV proteomes revealed two similar HLA-A2-restricted epitopes, HIV-Gag (SLYNTVATL [HIV-SL9]) and HCV-NS5b (ALYDVVSKL [HCV-AL9]). We found that 4 out of 20 HLA-A2-positive (HLA-A2(+)) HIV-infected individuals had CD8(+) T cells that recognized both the HIV-SL9 and HCV-AL9 epitopes. However, the AL9 epitope was generally shown to be a weak agonist. Although HCV-monoinfected individuals in our study did not show AL9-specific responses, we found that about half of HCV/HIV-coinfected individuals had dual responses to both epitopes. High dual T-cell recognition among coinfected subjects was usually due to separate T-cell populations targeting each epitope, as determined by pentamer staining. The one individual demonstrating cross-reactive T cells to both epitopes showed the most advanced degree of liver disease. In coinfected individuals, we observed a positive correlation between the magnitudes of T-cell responses to both the SL9 and the AL9 epitopes, which was also positively associated with the clinical parameter of liver damage. Thus, we find that HIV infection induces T cells that can cross-react to heterologous viruses or prime for T cells that are closely related in sequence. However, the induction of cross-reactive T cells may not be associated with control of disease caused by the heterologous virus. This demonstrates that degeneracy of HIV-specific T cells may play a role in the immunopathology of HCV/HIV coinfection.

Preserved MHC-II antigen processing and presentation function in chronic HCV infection

Individuals with chronic HCV infection have impaired response to vaccine, though the etiology remains to be elucidated. Dendritic cells (DC) and monocytes (MN) provide antigen uptake, processing, presentation, and costimulatory functions necessary to achieve optimal immune responses. The integrity of antigen processing and presentation function within these antigen presenting cells (APC) in the setting of HCV infection has been unclear. We used a novel T cell hybridoma system that specifically measures MHC-II antigen processing and presentation function of human APC. Results demonstrate MHC-II antigen processing and presentation function is preserved in both myeloid DC (mDC) and MN in the peripheral blood of chronically HCV-infected individuals, and indicates that an alteration in this function does not likely underlie the defective HCV-infected host response to vaccination.

Fibrosis and AST to platelet ratio index predict post-operative prognosis for solitary small hepatitis B-related hepatocellular carcinoma

PURPOSE

Although advanced liver fibrosis is crucial in the development of hepatocellular carcinoma (HCC) for patients with chronic hepatitis B, whether it is associated with the recurrence of HCC after resection remains obscure. This study was aimed to compare the outcomes for patients with minimal or advanced fibrosis in solitary small hepatitis B virus (HBV)-related HCC.

METHODS

This study enrolled 76 patients with small (<5 cm) solitary HBV-related HCC who underwent resection. The outcomes of patients with minimal and advanced fibrosis in non-tumor areas were compared. Serum markers were tested to assess the stage of hepatic fibrosis and to predict prognosis.

RESULTS

Fourteen patients with an Ishak fibrosis score of 0 or 1 were defined as having minimal fibrosis; the remaining 62 patients were defined as having advanced fibrosis. During a follow-up period of 77.0 ± 50.7 months, 41 patients died. The overall survival rate was significantly higher (P = 0.018) and recurrence rate was lower (P = 0.018) for patients in the minimal fibrosis group. Aspartate aminotransferase-platelet ratio index (APRI) exhibited the most reliable discriminative ability for predicting advanced fibrosis. The overall survival rate was significantly higher (P = 0.003) and recurrence rate was lower (P = 0.005) for patients with an APRI of 0.47 or less.

CONCLUSIONS

For patients with solitary small HBV-related HCC who underwent resection, minimal fibrosis is associated with a lower incidence of recurrence and with better survival. APRI could serve as a reliable marker for assessing hepatic fibrosis and predicting survival.

Evolving challenges in hepatic fibrosis

Continued elucidation of the mechanisms of hepatic fibrosis has yielded a comprehensive and nuanced portrait of fibrosis progression and regression. The paradigm of hepatic stellate cell (HSC) activation remains the foundation for defining events in hepatic fibrosis and has been complemented by progress in a number of new areas. Cellular sources of extracellular matrix beyond HSCs have been identified. In addition, the role of chemokine, adipokine, neuroendocrine, angiogenic and NAPDH oxidase signaling in the pathogenesis of hepatic fibrosis has been uncovered, as has the contribution of extracellular matrix stiffness to fibrogenesis. There is also increased awareness of the contribution of innate immunity and greater understanding of the complexity of gene regulation in HSCs and myofibroblasts. Finally, both apoptosis and senescence have been recognized as orchestrated programs that eliminate fibrogenic cells during resolution of liver fibrosis. Ironically, the progress that has been made has highlighted the growing disparity between advances in the experimental setting and their translation into new diagnostic tools and treatments. As a result, focus is shifting towards overcoming key translational challenges in order to accelerate the development of new therapies for patients with chronic liver disease.