Antinuclear antibodies (ANA) in chronic hepatitis C virus infection: correlates of positivity and clinical relevance

Antinuclear antibody (ANA) status predicts immune-related adverse events in liver cancer patients undergoing anti-PD-1 therapy

Immune-related adverse events (irAEs) clinically resemble autoimmune diseases, indicating autoantibodies could be potential biomarkers for the prediction of irAEs. This study aimed to assess the predictive value of peripheral blood antinuclear antibody (ANA) status for irAEs, considering the time and severity of irAEs, as well as treatment outcome in liver cancer patients administered anti-PD-1 therapy. Ninety-three patients with advanced primary liver cancer administered anti-PD-1 treatment were analyzed retrospectively. They were divided into the ANA positive (ANA+, titer ≥ 1:100) and negative (ANA-, titer < 1:100) groups. Development of irAEs, progression-free survival (PFS), and overall survival (OS) were assessed. Compared with ANA- patients, ANA+ cases were more prone to develop irAEs (43.3% vs. 19.2%, P = 0.031). With the increase of ANA titers, the frequency of irAEs increased. The time interval between anti-PD-1 therapy and the onset of irAEs was significantly shorter in ANA+ patients compared with the ANA- group (median, 1.7 months vs. 5.0 months, P = 0.022). Moreover, the time between anti-PD-1 therapy and irAE occurrence decreased with increasing ANA titer. In addition, PFS and OS were decreased in ANA+ patients compared with the ANA- group (median PFS, 2.8 months vs. 4.2 months, P = 0.043; median OS, 21.1 months vs. not reached, P = 0.041). IrAEs occur at higher frequency in ANA+ liver cancer patients undergoing anti-PD-1 therapy. ANA titer could help predict irAE development and treatment outcome in these patients.

The many faces and pathologic diagnostic challenges of autoimmune hepatitis

Autoimmune hepatitis (AIH) is an immune-mediated chronic inflammatory liver disease, characterized by hypergammaglobulinemia, the presence of specific autoantibodies, and typical abnormalities in liver histology. Prompt diagnosis and initiation of immunosuppressive treatment are necessary for both chronic and acute onset AIH to prevent progression to end-stage liver disease or fatal liver failure. However, the diagnosis of AIH is challenging mainly because of its heterogeneous clinical, serological and pathological features. Although portal lymphoplasmacytosis and interface hepatitis are the most typical histological features of AIH, many other histological features can be observed in AIH, including emperipolesis, hepatocyte rosettes, and Kupffer cell hyaline globules. Recent studies have questioned emperipolesis and hepatocyte rosette formation as typical features of AIH, and atypical clinical and histological presentations have also been recognized. This led an international working group to propose the modified AIH diagnostic criteria. However, it is well recognized that there are no pathognomonic characteristics that can be used to diagnose AIH and careful clinicopathological correlation is required to arrive at the correct diagnosis. The aim of this review is to summarize the histological features of AIH, its varied histopathologic spectrum, recent updates and major differential diagnoses in routine clinical practice.

A retrospective study of prevalence and pattern of international consensus on ANA patterns among patients with hepatitis C virus infection

Background

A previous study reported a 30% prevalence of various autoantibodies among patients with hepatitis C virus (HCV) infection. The International Consensus on Anti-Nuclear Antibody (ANA) Patterns was recently introduced to classify ANA patterns based on immunoassay on HEp-2 cells. There is no previous report with this newly developed classification to evaluate patients with HCV infection. The study aims to study the prevalence and pattern of ANA patterns among HCV-infected patients.

Methods

We retrospectively analyzed the medical records of patients with HCV infection from September 2020 to June 2021 at our institution. A positive ANA is defined as a titer of more than 1:320. We compared patient features among the positive and negative groups.

Results

Overall, 258 patients were enrolled-184 patients with negative ANA and 74 patients (28.7%) with positive ANA. The mean age was 67.3 in ANA positive group and 61.2 ANA negative group. Female was prominent with ANA positive and accounted for 63.5%. The most detected ANA pattern was AC-1(homogeneous) (25.9%), followed by AC-4(fine speckled) (25.2%) and AC-21(anti-mitochondrial antibody) (9.6%). In ANA positive group, we found a trend of lower HCV viral load (5.72 log₁₀ IU/ML vs. 6.02 log₁₀ IU/ML), lower alanine aminotransferase level (39.5 U/L vs. 44 U/L), and higher advanced fibrosis (F3 and F4) (38.5% vs. 26.1%). In addition, higher positive ANA (more than 1:640) is significantly associated with lower estimated glomerular filtration rate (eGFR) (77.76 vs. 87.94 mL/min/1.73 m², P = 0.044).

Conclusions

A high prevalence (28.7%) of ANA was found in patients with chronic hepatitis C. The presence of positive ANA is not related to the severity of their hepatic manifestation. However, higher positive ANA was significantly associated with lower eGFR.

High prevalence of antinuclear antibodies in patients with chronic hepatitis C virus infection

Background

Hepatitis C virus (HCV) infection is a serious public health concern due to its high prevalence and mortality rate. In chronic infection, HCV may induce autoimmune responses through the production of autoantibodies, including antinuclear antibodies (ANA).

Methods

We assessed the presence of ANA by indirect immunofluorescence using HEp-2 cells in 89 patients with chronic hepatitis C. We also collected data on epidemiological variables; clinical characteristics; and biochemical, hematological, molecular, and histopathological information from the patients to assess the impact of the presence of ANA in those patients.

Results

The prevalence of ANA in the patients was 20.2%, which was significantly higher than that found in healthy controls (2%). However, there was no association of this marker with epidemiological, clinical-laboratory, molecular or histopathological characteristics of hepatitis C, although a slightly higher prevalence of ANA was detected in women and in patients infected with subgenotype 1a. In a specific analysis, chronic HCV patients with the “rods and rings” cytoplasmic pattern had higher degrees of hepatic fibrosis than did ANA-negative patients.

Conclusions

The results confirm a greater predisposition to the presence of ANA in patients with HCV, which may be associated with a worse prognosis, especially in the presence of the “rods and rings” cytoplasmic pattern.

The Prevalence and Clinical Relevance of the DFS Immunofluorescence Staining Pattern in a Large ANA-Positive Cohort

Background

Although the dense fine speckled (DFS) immunofluorescence staining pattern has been studied by various researchers in recent years, its clinical associations remain unspecified. Thus, we performed a retrospective study in a non-selective population to explore the prevalence of this enigmatic antinuclear antibody (ANA) pattern and to determine its possible clinical associations with any identifiable pathology.

Methods

We retrieved the results of ANA testing ordered by various departments in 2019 to study the prevalence of DFS pattern. Demographic characteristics and clinical features of these participants were also collected from the electronic medical record system. Correlation analysis was made to study its clinical associations and a p-value < 0.05 was considered statistically significant.

Results

The prevalence of ANA positivity was 37.4% among 72,204 serum samples of which the median age was 44 (interquartile range: 31, 56) years old and 68.0% were women. The prevalence of the DFS staining pattern was 1.1% in the total population and accounted for 3.1% in the ANA-positive population. There were 97.6% of these cases displaying the DFS pattern with a low titer of ANA (≤1:320; starting serum dilution: 1:100). We found that this pattern correlated with several pathological conditions, such as skin disorders (25.1%), alopecia (4.6%), and obstetric complications (6.6%).

Conclusion

The presence of the DFS immunofluorescence staining pattern may accompany several pathological conditions and may be a signal of localized inflammation within certain organs or tissues, especially the skin.

Autoantibodies and Rheumatologic Manifestations in Hepatitis C Virus Infection

HCV is a virus that can cause chronic infection which can result in a systemic disease that may include many rheumatologic manifestations such as arthritis, myalgia, sicca syndrome, cryoglobulinemia vasculitis as well as other non-rheumatological disorders (renal failure, onco-haematological malignancies). In this population, the high frequency of rheumatoid factor (45-70%), antinuclear (10-40%) and anticardiolipin (15-20%) antibodies is a B-cell mediated finding sustained by the infection. However, the possibility that a primitive rheumatic pathology may coexist with the HCV infection is not to be excluded thus complicating a differential diagnosis between primitive and HCV-related disorders.

Hepatic pathological features in naïve patients with chronic hepatitis C who have developed thyroid disorder

Knowing the hepatic pathological features encountered in patients with chronic hepatitis C (CHC) and the fact that extrahepatic manifestations occur only in people with certain characteristics of the immune system, we tried to evaluate, qualitatively and semi-quantitatively, the liver pathological aspects encountered in 96 patients with CHC, previously untreated with Interferon (naïve), who showed or did not show signs of thyroid disorder (TD), hospitalized in the 2nd Medical Clinic of the Emergency County Hospital, Craiova, Romania, within a period of five years (2007-2012). Following hormonal, immunological, and thyroid ultrasound investigations, 14 (14.58%) of the 96 patients showed signs of TD. The main clinical forms of TD in the studied patients with CHC were autoimmune thyroiditis and subclinical hypothyroidism. In the patients with CHC with TD, we found mild chronic hepatitis in 14.28% of cases, the appearance of moderate chronic hepatitis was found in 71.42% patients, and the appearance of severe chronic hepatitis was found in 14.28% patients, while in the patients with CHC without TD we found chronic mild hepatitis in 62.19% of cases, the appearance of moderate chronic hepatitis was met in 32.92% patients, and the appearance of severe chronic hepatitis was found in 4.87% of patients. Mild and moderate fibrosis were found only in CHC patients without TD in a percentage of 25.6% and 65.85%, respectively, while severe fibrosis was found at 12.19% among CHC patients without TD and 92.85% among CHC patients with TD. The pathological aspect of liver cirrhosis was found only in those with TD (7.14%). In conclusion, the pathological features which define the liver necroinflammatory process, as encountered at the pathological examination in CHC patients with TD are the same as in any active chronic hepatitis, the differences being represented by the higher percentage of the periportal and the preseptal necrosis (piecemeal necrosis), as well as by the higher score of portal inflammation. In addition, the severe hepatic fibrosis and the histopathological appearance of the liver cirrhosis have only defined the cases of CHC with TD.

Anti-rods/rings autoantibody and IMPDH filaments: an update after fifteen years of discovery

Autoantibodies to unknown subcellular rod and ring-shaped structures were first discovered in sera from hepatitis C patients in 2005. Early studies showed a strong association between these anti-rods/rings antibodies (anti-RR) and the standard of care interferon-α plus ribavirin combination therapy (IFN/RBV), suggesting that anti-RR are drug-induced autoantibodies. In the context of hepatitis C, anti-RR have been linked with relapse from or lack of response to IFN/RBV in some patient cohorts. However, examples of anti-RR in other diseases and healthy individuals have also been reported over the years, although anti-RR remains a rare autoantibody response in general. The advent of new direct-acting antiviral drugs for chronic hepatitis C and studies of anti-RR from different parts of the world are also beginning to change the perception of anti-RR. The nucleotide biosynthetic enzyme inosine monophosphate dehydrogenase (IMPDH) has been identified as the major autoantigen recognized by anti-RR. Coincidentally, the assembly of IMPDH into micron-scale rod and ring-shaped structures was discovered around the same time as anti-RR. Knowledge of the fundamental biological properties and cellular functions of these structures, referred to as "IMPDH filaments" by cell biologists, has advanced in parallel to anti-RR antibodies. Recent studies have revealed that IMPDH filament assembly is a mechanism to prevent feedback inhibition of IMPDH and is therefore important for the increased nucleotide production required in hyperproliferating cells, like activated T cells. Fifteen years later, we review the history and current knowledge in both the anti-RR autoantibody and IMPDH filament fields. TAKE-HOME MESSAGE: Anti-rods/rings are recognized as an example of a drug-induced autoantibody in hepatitis C patients treated with interferon and ribavirin, although new studies suggest anti-rods/rings may be detected in other contexts and may depend on unknown environmental or genetic factors in different populations. Recent data suggest that the assembly of IMPDH into rod and ring structures, the targets of anti-rods/rings autoantibody, is a mechanism for hyperproliferating cells, like activated T cells, to maintain increased guanine nucleotide levels to support rapid cell division.

Anti-rod and ring antibodies in patients with chronic hepatitis C using direct-acting antivirals

Anti-rods and rings (anti-RR) antibody induction is related to the combination of interferon and ribavirin in the treatment of hepatitis C virus (HCV) infection. If the main factor leading to this autoimmune reaction is the combination of these drugs, is not well known, but in vitro studies shows that ribavirin alone can induce rods and rings structures. New direct-acting antivirals (DAAs) permit HCV treatment without needing interferon but may be associated with ribavirin in the most difficult-to-treat patients. The aim of this study is to evaluate the occurrence of anti-RR in patients with chronic HCV infection, before and after 12 weeks of treatment with DAAs, with and without ribavirin. From Jun 2016 to Oct 2017, 52 HCV-infected patients were screened for anti-RR before and after DAA therapy, including sofosbuvir, daclatasvir, simeprevir, and ribavirin. Serum samples were analyzed using indirect immunofluorescence. The anti-RR was present in 11 (21%) of the 52 patients (51.9% male and mean age of 59.1 years) before using DAAs. All of them had been previously treated and previous exposed to interferon/ribavirin, with exposure time to ribavirin associated with the presence of anti-RR. After 12 weeks of DAA treatment, 3 patients (5.7%) developed the antibody in low titers, and two of them (66%) were interferon/ribavirin experienced. Only one of the 29 naïve patients (3.44%) developed anti-RR during the current treatment. Anti-RR was present in patients previously treated with interferon/ribavirin and can emerge after DAA treatment probably at a lower frequency than after interferon/ribavirin treatment.

Long-term persistence of anti-rods and rings antibodies in patients with chronic hepatitis C after antiviral treatment

Anti-rods and rings (anti-RR) antibodies are related to hepatitis C virus (HCV) in patients treated with pegylated interferon (PEG-IFN) and ribavirin (RBV). Only RBV induces rods/rings structures in vitro; but in vivo, the antibody appearance is related to the combination of these drugs, because data about patients using just one of these drugs alone is missing. Some studies suggest disappearance of these antibodies over time. The aim of this study was to describe the occurrence of anti-RR in patients with chronic hepatitis C treatment-naïve or previously PEG-IFN/RBV-experienced, evaluating the persistence of anti-RR antibodies long after PEG-IFN/RBV treatment. From 2016 to 2017, 70 HCV-infected patients were screened for anti-RR using indirect immunofluorescence. Demographic and clinical data about previous treatments against HCV were assessed. Thirty-four patients (49%) had been previously treated with PEG-IFN/RBV and the average time since they had received the last antiviral treatment was 85.4 months. Anti-RR seropositivity was detected in 16 patients (23%), and all of these had used PEG-IFN/RBV (corresponding to 47% of experienced patients). Previous antiviral treatment and previous exposure time to RBV were associated with anti-RR positivity. Median time elapsed since last treatment was similar between anti-RR-positive and anti-RR-negative patients. Anti-RR seropositivity was not observed in treatment-naïve patients, but was detected in almost half of patients previously treated with PEG-IFN and RBV, even after a long period without exposure to these drugs. This antibody was related to extended prior exposure to ribavirin.

Distinctive features of positive anti-cell antibody tests (indirect immunofluorescence on HEp-2 cells) in patients with non-autoimmune diseases

OBJECTIVE

The objective of this study was to determine whether characteristics of positive results in the indirect immunofluorescence assay on HEp-2 cells for anti-cell antibodies (HEp-2 IFA) differ between patients with non-autoimmune diseases (NADs) and patients with systemic autoimmune rheumatic diseases (SARDs).

METHODS

Cross-sectional observational study comparing HEp-2 IFA test results in three groups: (a) 558 NAD patients comprising four subgroups (cancer ( n = 95), infectious diseases ( n = 148), psychiatric diseases ( n = 163), common non-infectious chronic diseases ( n = 152)); (b) 194 SARD patients; (c) 1217 healthy individuals (HIs). Sera were tested at 1:80 dilution and diluted to the end titer. Slides were analyzed by two independent blinded examiners.

RESULTS

A positive HEp-2 IFA test occurred in 102 (18.3%) NAD patients, 170 (87.6%) SARD patients and 150 (12.3%) HIs. The four NAD subgroups did not differ regarding HEp-2 IFA frequency, titer or pattern. HEp-2 IFA titer was higher in NAD patients than in HIs and both had lower titer than SARD patients. Nuclear dense fine speckled pattern was more frequent in NAD patients and HIs than in SARD patients ( p < 0.001). Nuclear homogeneous and nuclear coarse speckled patterns were more frequent in SARD patients than in the other groups ( p < 0.001). The nuclear fine speckled pattern was prevalent in all three groups, but presented a gradient in titer across them; HIs and NAD patients had low and intermediary titers, which were significantly lower than in SARD patients ( p < 0.001).

CONCLUSION

Positive HEp-2 IFA frequency, pattern and titer present differential features in NAD and SARD patients, and this attribute adds value to the test in the diagnosis of SARDs.

Divergent Roles of Antiself Antibodies during Infection

Antiself antibodies are most commonly associated with autoimmune disorders, but a large body of evidence indicates that they are also present in numerous infectious diseases. These autoimmune antibodies appear transiently during infection with a number of viruses, bacteria, and parasites and in some cases have been associated with the development of autoimmune disorders that develop after infection has been cleared. Traditionally these infection-associated autoantibodies are considered an erroneous byproduct of a legitimate immune response, but their possible role in the clearance of microbes and infected cells or inhibition of host-cell invasion suggests that they may be present because of their beneficial protective role against various infections.

High prevalence of a variety of autoantibodies in a population of hepatitis C virus-infected individuals

Hepatitis C virus (HCV) infection has been related to self-reactivity, extrahepatic manifestations and autoimmune diseases. The main goals of this work were to study the prevalence of autoantibodies and their relationship with viral titers and biochemical markers of hepatic damage in patients infected with HCV. Autoantibodies (ANA, AMA, SMA, APC, LKM, DNAds, ANCA, ATG and RF) were determined in 73 individuals with chronic HCV infection and 44 healthy volunteers. The presence of these antibodies was related to demographic variables, viral titers and biochemical parameters. A high prevalence of autoantibodies, particularly for RF, that was associated with female gender was observed in HCV-infected patients. In addition, SMA, ANA and ATG showed increased frequencies in HCV infection. Interestingly, the concurrent detection of SMA and more than one autoantibody was associated with high gGT levels. Notably, concurrent higher gGT, HCV and SMA levels were observed in male patients as compared to their female counterparts. These results indicate a relationship between HCV infection and the concurrent detection of various autoantibodies in the absence of symptoms of autoimmune diseases. They also suggest a link among the presence of a variety of autoantibodies simultaneously with SMA, increased gGT levels and HCV titers in a population of male patients.

Autoantibodies in chronic hepatitis C virus infection: impact on clinical outcomes and extrahepatic manifestations

Goals

To examine the role that autoantibodies (auto-abs) play in chronic hepatitis C virus (HCV) regarding demographics, presence of extrahepatic manifestations and long-term outcomes in a large US cohort.

Background

Auto-abs have been reported to be prevalent in patients with chronic HCV infection, but data on the natural history of these patients are limited.

Study

The study included 1556 consecutive patients with HCV without concurrent HIV and/or HBV who had testing for antinuclear antibody (ANA), antimitochondrial antibody (AMA), antismooth muscle antibody (ASMA) and/or antiliver kidney microsomal antibody (LKM). Primary outcomes included development of cirrhosis, hepatic decompensations, hepatocellular carcinoma (HCC), mortality and/or sustained virological response (SVR) to antiviral therapy.

Results

A total of 388 patients tested positive for any auto-ab (ANA 21.8%, ASMA 13.3%, AMA 2.2% and LKM 1.2%). Patients who tested positive versus negative were more likely to be women (29.3% vs 20.9%, p<0.001) and less likely to achieve SVR with most treated patients receiving interferon-based therapies (37.2% vs 47.1%, p=0.031). There was no difference between groups for baseline laboratory data, disease state or rate of extrahepatic manifestations (42.8% vs 45.0%, p=0.44). Kaplan-Meier analysis revealed no statistically significant difference between groups for the 10-year development of cirrhosis, hepatic decompensations, HCC nor survival. Furthermore, auto-ab positivity was only found to be a predictor for a lower rate of SVR on multivariate analysis (adjusted OR=1.61, 95 %  CI 1.00 to 2.58, p=0.048).

Conclusions

In our cohort, auto-ab positivity was common, especially in women, and predicted a lower rate of SVR but otherwise had no impact on the natural history of chronic HCV or presence of extrahepatic manifestations.

ANA testing in the presence of acute and chronic infections

Autoantibody testing is performed to help diagnose patients who have clinical symptoms suggestive of possible autoimmune diseases. Antinuclear antibodies (ANA) are present in many systemic autoimmune conditions such as systemic lupus erythematosus (SLE). However, a positive ANA test may also be seen with non-autoimmune inflammatory diseases, including both acute and chronic infections. When the ANA test is used as an initial screen in patients with non-specific clinical symptoms, such as fever, joint pain, myalgias, fatigue, rash, or anemia, the likelihood of a positive result due to infection will increase, especially in children. This article identifies acute and chronic infectious diseases that are likely to produce a positive ANA result and summarizes recent literature addressing both the causes and consequences of these findings.

Autoantibody profiles in autoimmune hepatitis and chronic hepatitis C identifies similarities in patients with severe disease

AIM

To determine how the auto-antibodies (Abs) profiles overlap in chronic hepatitis C infection (CHC) and autoimmune hepatitis (AIH) and correlate to liver disease.

METHODS

Levels of antinuclear Ab, smooth muscle antibody (SMA) and liver/kidney microsomal-1 (LKM-1) Ab and markers of liver damage were determined in the sera of 50 patients with CHC infection, 20 AIH patients and 20 healthy controls using enzyme linked immunosorbent assay and other immune assays.

RESULTS

We found that AIH patients had more severe liver disease as determined by elevation of total IgG, alkaline phosphatase, total serum bilirubin and serum transaminases and significantly higher prevalence of the three non-organ-specific autoantibodies (auto-Abs) than CHC patients. Antinuclear Ab, SMA and LKM-1 Ab were also present in 36% of CHC patients and related to disease severity. CHC cases positive for auto-Abs were directly comparable to AIH in respect of most markers of liver damage and total IgG. These cases had longer disease duration compared with auto-Ab negative cases, but there was no difference in gender, age or viral load. KLM-1⁺ Ab CHC cases showed best overlap with AIH.

CONCLUSION

Auto-Ab levels in CHC may be important markers of disease severity and positive cases have a disease similar to AIH. Auto-Abs might have a pathogenic role as indicated by elevated markers of liver damage. Future studies will unravel any novel associations between these two diseases, whether genetic or other.

The prevalence of autoantibody and its relationship with genotypes of hepatitis C virus in patients with chronic hepatitis C virus infection

The prevalence of autoantibody in the patients with chronic hepatitis C infection, and the relationship between the autoantibodies and HCV genotypes were investigated in this study. One hundred and eight anti-HCV positive and 86 anti-HCV negative patients were included in the study. Anti-HCV were studied by enzyme immunassay (EIA). HCV RNA was determined by real time polymerase chain reaction (PCR) and HCV genotypes were determined by a reverse-line blot hybridization. Anti-nuclear antibodies (ANA), anti-smooth muscle antibodies (ASMA), Anti-mitochondrial antibodies (AMA), liver kidney microsomal antibodies (LKM) were detected by indirect immunofluorescence assay. Among patients, 13 (12.03%) of 108 were positive for at least one autoantibody. The positivity was not observed in control group. The most prevalent autoantibody in anti-HCV positive group was ANA. ANA was positive in six HCV patients with genotype 1. In HCV patients with genotype 1, the frequencies of ANA, ASMA, AMA and LKM1 were six, two, three and one, respectively. In HCV patients with genotype 2, ANA was positive one patient and ASMA, AMA and LKM1 were not detected in HCV patients with genotype 2. In conclusion, the autoantibodies in patients with chronic hepatitis C in the study were low as compared to those reported in previous studies.

Algorithmic Approach With Clinical Pathology Consultation Improves Access to Specialty Care for Patients With Systemic Lupus Erythematosus

OBJECTIVES

Harris Health System (HHS) is a safety net system providing health care to the underserved of Harris County, Texas. There was a 6-month waiting period for a rheumatologist consult for patients with suspected systemic lupus erythematosus (SLE). The objective of the intervention was to improve access to specialty care.

METHODS

An algorithmic approach to testing for SLE was implemented initially through the HHS referral center. The algorithm was further offered as a "one-click" order for physicians, with automated reflex testing, interpretation, and case triaging by clinical pathology.

RESULTS

Data review revealed that prior to the intervention, 80% of patients did not have complete laboratory workups available at the first rheumatology visit. Implementation of algorithmic testing and triaging of referrals by pathologists resulted in decreasing the waiting time for a rheumatologist by 50%.

CONCLUSIONS

Clinical pathology intervention and case triaging can improve access to care in a county health care system.

Autoantibodies in chronic hepatitis C: A clinical perspective

Non-organ-specific autoantibodies and thyroid autoantibodies have been frequently found in chronic carriers of hepatitis C virus (HCV). With respect to endomysial antibodies and tissue transglutaminase, it is controversial whether the prevalence of gluten-related seromarkers is higher in patients with HCV. In such cases, in addition to acknowledging any currently existing autoimmune disease, recognizing the risk of the patient developing an autoimmune disease during interferon (IFN)-based treatment must be a principle concern. From a clinical point-of-view, the presence of autoantibodies arouses suspicion that an autoimmune disease may be present or may be precipitated by IFN-based HCV treatment. In this paper, we review the prevalence of autoantibodies in individuals with hepatitis C, the clinical significance of these autoantibodies, and the approach recommended for such situations.

Serum autoantibodies positivity prevalence in patients with chronic HCV and impact on pegylated interferon and ribavirin treatment response

BACKGROUND & AIMS

Prevalence of serum autoantibodies in chronic hepatitis C (HCV) patients is higher than that in the general population. Interferon may induce autoimmune manifestations in patients treated with peg-interferon and ribavirin. Effect of autoantibody seropositivity and treatment response are limited and controversial. To detect the prevalence of serum autoantibodies in patients with chronic HCV and impact on histopathology and treatment response.

METHODS

Retrospective study including 3673 Egyptian chronic HCV naïve patients enrolled in the Egyptian national programme for HCV treatment with pegylated interferon and ribavirin in the years 2007-2010. Antinuclear antibody (ANA) was determined by ELISA considered positive with a titre ≥ 1:40 by indirect immunofluorescence. ANA-positive patients pre treatment workup including serum aminotransferases, thyroid profile and liver biopsy, follow-up during treatment and sustained virological response (SVR) were assessed compared to ANA-negative patients.

RESULTS

Serum ANA was positive in 1.6% of the studied patients. There were no statistically significant differences concerning the demographic, biochemical and histopathological data in ANA positive and negative patients. SVR was comparable between ANA-positive and ANA-negative patients (67.8% and 61.3% respectively). Follow-up treatment; ANA-positive patients' did not experience statistically significant haematological complications, flare-up of serum transaminases, thyroid dysfunction. No systemic autoimmune disorders developed during follow-up.

CONCLUSIONS

ANA positivity is not a factor in chronic HCV disease progression and does not affect the treatment response. Pegylated interferon and ribavirin therapy is safe and effective in autoantibodies-positive chronic HCV patients with no need for further follow-up or worry during the treatment in absence of systemic autoimmune disorders.

Autoantibody profile in individuals with chronic hepatitis C

INTRODUCTION

Autoantibodies are often produced during infection with chronic hepatitis C virus (HCV), but it remains controversial whether they influence the biochemical profile and histological features of this disease. Therefore, this current study sought to describe these autoantibodies and evaluate their impact on the clinical and histological presentation of hepatitis C.

METHODS

This cross-sectional analytical study assessed patients with HCV (RNA+) from October 2011 to July 2012.

RESULTS

This study included 66 patients, with a mean age of 53.2±10.5 years. Of these patients, 60.6% were male, and 54.3% presented with genotype 1. Non-organ-specific autoantibodies (NOSA) were detected in 24% of the patients; of these, 7.6% were anti-mitochondrial antibodies (AMA+), 26.7% were anti-smooth muscle antibodies (SMA+) and 6.8% were liver kidney microsomal type 1 antibodies (LKM1+). With respect to the thyroid autoantibodies, 7.4% were anti-peroxidase (ATPO+) antibodies, and none were anti-thyroglobulin (ATG+) antibodies. Regarding celiac disease autoantibodies, 5.8% were endomysial antibodies (EMA+), and no transglutaminase (TTG+) antibodies were detected. Cryoglobulins were found in 2.1% of patients. When NOSA+ individuals were compared to patients without the presence of NOSAs, they exhibited higher median alkaline phosphatase (0.7 vs. 0.6 xULN; p=0.041), lower median platelet counts (141,500.0 vs. 180,500.0/mm 3 ; p=0.036), lower mean prothrombin activity (72.6±11.5% vs. 82.2±16.0%; p=0.012) and an increased prevalence of significant fibrosis (E≥2) (45.5% vs. 18.2%; p=0.012). There was also a tendency for a greater proportion of NOSA+ cases to have marked periportal activity (APP≥3) (44.5% vs. 15.6%; p=0.087).

CONCLUSIONS

In addition to the high prevalence of autoantibodies associated with HCV infection, it was observed that NOSA positivity was associated with a more severe histological and biochemical profile of hepatitis C infection.

Screening for autoantibodies in chronic hepatitis C patients has no effect on treatment initiation or outcome

Autoantibodies in hepatitis C virus-infected patients may indicate autoimmune hepatitis or other immune-mediated diseases. This may impact safety and efficacy of interferon-based therapy of chronic hepatitis C. We investigated the association between a positive test result for a variety of autoantibodies and the initiation and efficacy of therapy for chronic hepatitis C. We analysed an observational cohort of 24 306 patients for an association between autoantibodies and treatment outcome. 8241 patients were tested simultaneously for antinuclear antibodies (ANA), liver kidney microsomal antibodies (LKM), smooth muscle antibodies (SMA) and antimitochondrial antibodies (AMA). Matched-pair analysis was performed matching one autoantibody-positive patient to three controls. Control patients had negative tests for all four antibodies. Analyses were performed for patients with a single positive autoantibody test and for patients with multiple positive autoantibody tests. A positive test result for ANA, LKM, SMA or AMA did not affect the physician's decision to initiate therapy with pegylated interferon and ribavirin. In addition, a positive test for one or multiple autoantibodies did not adversely affect sustained virologic response. There was no difference in fibrosis stage or alanine transaminase at baseline or during therapy irrespective of antibody status. Thyroid dysfunction was more frequent in patients with positive LKM antibodies (P = 0.004). Initiation of therapy for chronic hepatitis C and outcome were not affected by the presence of ANA, LKM, SMA or AMA. Routine testing of these autoantibodies seems not warranted. Determination of autoantibodies should be guided by individualized clinical decisions.

Clinical associations and potential novel antigenic targets of autoantibodies directed against rods and rings in chronic hepatitis C infection

Background

Chronic hepatitis C virus (HCV) infection is frequently associated with extrahepatic autoimmune disorders while interferon (IFN) and ribavirin treatment may exacerbate these conditions. Autoantibodies from HCV patients identify a novel indirect immunofluorescence (IIF) pattern on HEp-2 cells characterized by cytoplasmic rods and rings (RR). Our objectives were to determine the prevalence and clinical associations of RR autoantibodies in HCV patients, and identify related novel autoantibody targets.

Methods

Sera from 315 patients with HCV (301 treatment naive, 14 treated with interferon and/or ribavirin) were analyzed for the presence of RR antibodies by IIF on commercially available HEp-2 cell substrates. Antibodies to inosine monophosphate dehydrogenase 2 (IMPDH2) and cytidine triphosphate synthase 1 (CTPS1) were detected by addressable laser bead assay and other potential targets were identified by immunoscreening a protein microarray. Clinical and demographic data including HCV genotype, mode of infection, prior antiviral therapy, and histological findings were compared between RR antibody positive (RR+) and negative (RR-) patients.

Results

The median age of the HCV cohort was 51 years, 61% were male, and 76% were infected with HCV genotype 1 (G1). Four percent (n=14) had been treated with IFN-based therapy (IFN monotherapy, n=3; IFN/ribavirin, n=11); all had a sustained virologic response. In total, 15 patients (5% of the cohort) were RR+. RR+ and RR- patients had similar demographic and clinical characteristics including age, sex, mode of HCV infection, prevalence of the G1 HCV genotype, and moderate to severe fibrosis. Nevertheless, RR+ patients were significantly more likely than RR- cases to have been treated with IFN-based therapy (33% vs. 3%; adjusted odds ratio 20.5 [95% confidence interval 5.1-83.2]; P<0.0005). Only 1/10 RR positive sera had detectable antibodies to IMPHD2 and none had antibodies to CTPS1. Potentially important autoantibody targets identified on protein arrays included Myc-associated zinc finger protein (MAZI) and ankyrin repeat motif.

Conclusion

The majority of HCV patients with RR autoantibodies previously received IFN/ribavirin antiviral therapy. Further studies are necessary to determine the genesis of intracellular RR and elucidate the clinically relevant autoantigens as well as the clinical and prognostic significance of their cognate autoantibodies.

Hepatitis C virus infection and autoimmunity

According to the WHO estimates, the rate of hepatitis C virus (HCV) infection is approximately 3% in the world, and approximately 170 million people are infected with HCV. About 3.15 million new cases of HCV infection are diagnosed each year. Multiple autoantibodies can often be detected in patients with chronic HCV infection. Elucidation of the relationship between HCV infection and autoimmunity will open new perspectives for understanding the pathogenesis of HCV infection and the natural history of hepatitis C.

Longitudinal study of a human drug-induced model of autoantibody to cytoplasmic rods/rings following HCV therapy with ribavirin and interferon-α

Background

A novel pattern in the indirect immunofluorescence antinuclear antibody assay on HEp-2 cells (IIF-HEp-2) characterized by cytoplasmic rods and rings (RR) was reported in HCV patients, but stringent disease specificity studies and longitudinal analysis are lacking. We investigated the clinical significance of anti-RR in an HCV cohort with up to a 12-month treatment follow up.

Methodology/Results

597 patients (342 HCV, 55 HCV/HIV, 200 non-HCV) were screened and titered for anti-RR. Serial samples were available from 78 of 176 treated and 27 of 166 untreated patients. Anti-RR was detected in 14.1% of 342 HCV patients, 9.1% of 55 HCV/HIV, 3.4% of 29 Hepatitis B, and none of 171 non-HCV (p<0.0001; HCV versus non-HCV). Anti-RR was present in 38% of 108 patients receiving interferon-α/ribavirin, but none in 26 receiving either interferon-α or ribavirin, or 166 untreated patients (p<0.0001). Other IIF-HEp-2 patterns were more frequently associated with interferon-α treatment alone (52.2%) as compared to interferon-α/ribavirin (25%), ribavirin alone (33.3%), and no therapy (26.5%). Anti-RR frequency was not associated with sex, age, ethnicity, HCV genotype or viral load. Anti-RR occurred only after initiation of treatment, beginning as early as 1 month (6%), but by the sixth month >47% tested positive for anti-RR. The anti-RR titer generally increased with sustained treatment and remained high in 53% of patients. After treatment, anti-RR titer was negative in 41%. Non-responders to HCV therapy were 77% in anti-RR-positive versus 64% in anti-RR-negative patients. Response to treatment was not associated with anti-RR titer or the dynamics of anti-RR reactivity during and after treatment.

Conclusions

The exquisite association of anti-RR reactivity with combined interferon-α/ribavirin therapy in HCV patients represents a unique model for drug-induced autoantibody generation in humans as demonstrated by the fact that a significant fraction of patients who have anti-RR during therapy becomes anti-RR-negative after completion of therapy.

Antinuclear antibody titer and treatment response to peginterferon plus ribavirin for chronic hepatitis C patients

Positive serum antinuclear antibody (ANA) is not infrequent in chronic hepatitis C virus (HCV)-infected patients. This prospective study evaluated the impact of ANA on the response to and safety of peginterferon/ribavirin combination therapy for chronic hepatitis C patients in clinical practice. We enrolled 243 consecutive patients who were treated with a 24-week regimen of peginterferon-α plus ribavirin, with a 24-week follow-up period. ANA titer was determined before antiviral treatment. The primary end-point was sustained virological response (SVR), defined as HCV RNA <50 IU/mL throughout the follow-up period. Overall, 187 (77.0%) patients experienced a SVR. In the 105-patient HCV genotype non-1 group, patients with ANA titer ≥1:80 had a significantly lower SVR rate than those with ANA titer <1:80 (67.7% vs. 95.8%, respectively, p = 0.013). In contrast, in the 138-patient HCV genotype 1 group, the SVR rate did not differ between patients with and without ANA titer ≥1:80. Multivariate regressive analyses showed that ANA ≥1:80, age and HCV RNA levels were independent factors associated with SVR in HCV genotype non-1 patients; whereas HCV RNA levels and hepatic fibrosis were prognostic predictors of SVR in HCV genotype 1 patients. The frequencies of adverse events were similar between patients with and without ANA seropositivity. Peginterferon/ribavirin combination therapy is effective and safe in ANA-positive chronic hepatitis C patients. A high ANA titer was a negative prognostic factor for treatment response in HCV genotype non-1 patients.

Cytoplasmic rods and rings autoantibodies developed during pegylated interferon and ribavirin therapy in patients with chronic hepatitis C

BACKGROUND

Serum autoantibodies are frequently detected in patients with chronic HCV infection, reflecting the wide spectrum of immune reactions related to this virus. In the present study, a novel autoantibody to cytoplasmic rods and rings (RR) in chronic HCV patients was characterized.

METHODS

Sera from 75 previously untreated HCV patients were investigated by indirect immunofluorescence using HEp-2 cell substrate before and during pegylated interferon (PEG-IFN)/ribavirin (RBV) therapy. HEp-2 cells were cultured and fixed either following standard protocols or with the addition of RBV in culture medium.

RESULTS

In 15 out of 75 (20%) patients, analysis revealed the presence of antibodies to rod-like cytoplasmic structures ranging approximately 3-10 μm in length and rings approximately 2-5 μm in diameter. These RR structures became detectable in >95% of cells after addition of RBV in culture medium, whereas they were absent in untreated cells. Anti-RR antibodies were found in sera collected during PEG-IFN/RBV treatment only, but never detected before antiviral therapy nor in control groups. More importantly, these anti-RR antibodies were more often detected in non-responder/relapsers than in responder patients (33% versus 11%; P-value =0.037).

CONCLUSIONS

An RBV-induced autoantibody was identified to a new cytoplasmic autoantigenic structure developed in HCV patients after PEG-IFN/RBV and this same structure can be induced by RBV in in vitro culture. Owing to the onset of anti-RR antibodies in PEG-IFN/RBV-treated patients and their association with a treatment failure, studies are deemed necessary to clarify whether anti-RR plays a role in the response to PEG-IFN/RBV therapy.

Clinical features and effect of antiviral therapy on anti-liver/kidney microsomal antibody type 1 positive chronic hepatitis C

BACKGROUND/AIMS

Anti-liver/kidney microsomal antibody type 1 (anti-LKM1), a serological marker of type 2 autoimmune hepatitis, is also detected in a small proportion of patients with hepatitis C. This study aimed to evaluate clinical features and effect of antiviral therapy in patients with hepatitis C who are anti-LKM1 positive.

METHODS

Sixty consecutive anti-LKM1 positive and 120 age and sex-matched anti-LKM1 negative chronic hepatitis C patients were assessed at diagnosis and during follow-up. Of these, 26 anti-LKM1 positive and 72 anti-LKM1 negative received antiviral therapy. Anti-LKM1 was detected by indirect immunofluorescence and immunoblot. Number of HCV-infected hepatocytes and intrahepatic CD8+ lymphocytes was determined by immunohistochemistry.

RESULTS

At diagnosis anti-LKM1 positive patients had higher IgG levels and more intrahepatic CD8+ lymphocytes (p 0.022 and 0.046, respectively). Viral genotypes distribution and response to therapy were identical. Hepatic flares during antiviral treatment only occurred in a minority of patients in concomitance with anti-LKM1 positivity.

CONCLUSIONS

Immune system activation is more pronounced in anti-LKM1 positive patients with hepatitis C, possibly representing the expression of autoimmune mechanisms of liver damage. Antiviral treatment is as beneficial in these patients as in anti-LKM1 negative patients, and the rare necroinflammatory flares are effectively controlled by corticosteroids, allowing subsequent resumption of antiviral therapy.

Autoantibodies in chronic hepatitis C virus infection and their association with disease profile

Autoantibodies are commonly detected in chronic hepatitis C (HCV) but their significance remains uncertain. We assessed the prevalence of anti-nuclear (ANA) and anti-smooth muscle (ASM) antibodies within a cohort of 963 treatment-naïve HCV patients. We also assessed for differences between autoantibody-positive and autoantibody-negative patients in demographics, markers of disease activity and response to anti-viral treatment. One hundred and seventy-two patients (17.9%) had at least one autoantibody, of which were 104 (10.8%) ASM, 54 (5.6%) ANA and 14 (1.5%) positive for both. Autoantibody-positive patients were older (43 vs 39 years, P = 0.001) caused by an age-related increase in ANA (but not ASM). There were no differences in gender, alcohol intake, ethnicity or viral genotype. The presence of autoantibodies, and specifically ASM, was associated with an increase in interface hepatitis score amongst men (1.1 vs 0.8, P = 0.005) but no difference in other necroinflammatory measures, liver function tests or immunoglobulins (Ig). There was no difference in initial fibrosis stage or rate of fibrosis progression. Autoantibodies did not affect response to anti-viral treatment. We conclude that autoantibodies are frequent in HCV infection. Anti-nuclear antibodies increase with age, whereas ASM antibodies are associated with interface hepatitis in men. Neither autoantibody carries increased risk of fibrosis progression or failure of therapy.

Antinuclear antibody positivity in patients with chronic hepatitis C: clinically relevant or an epiphenomenon?

BACKGROUND

Serum autoantibodies such as antinuclear antibody (ANA) are frequently detected in patients with chronic hepatitis C virus (HCV) infection, but its relevance is a matter of discussion.

AIM

To assess the association of ANA positivity with clinical and histological features, and with the outcome of antiviral therapy in patients with HCV infection.

METHODS

Baseline samples from patients with hepatitis C treated with interferon and ribavirin were tested for ANA positivity by indirect immunofluorescence.

RESULTS

The mean age was 48.3+/-11.1 years and 56% were men. Among 234 included patients, 22 patients (9.4%) were positive for ANA. These patients showed significantly higher median alanine aminotransferase level (3.52 vs. 2.39 x upper limit of normal, P=0.009) when compared with ANA-negative patients. Fibrosis stage and necroinflammatory grading were not influenced by ANA positivity. Sustained virological response (SVR) rates were similar between ANA-positive and ANA-negative patients (27 vs. 29%, P=0.882). Alanine aminotransferase flares (> or = 1.5-fold the baseline) during treatment were observed in 28 patients (12%), irrespective of the presence of ANA and without any clinical significance.

CONCLUSION

Among HCV patients, ANA positivity seems to represent an immunological epiphenomenon. It neither influences clinical, biochemical, and histological features of chronic hepatitis C nor predicts response to antiviral treatment.

Clinical characteristics of patients with hepatitis C virus-related chronic liver disease seropositive for anticentromere antibody

The association between anticentromere antibody (ACA) and hepatitis C virus (HCV) infection remains unclear. We subjected eight patients with HCV-related chronic liver disease (CLD) seropositive for ACA to a battery of clinical and laboratory tests. The patient cohort was dominated by females, and four of the eight (50%) patients had a concomitant autoimmune disease. All of the patients had high titers of ACA (>or=1:320). The histological activity index scores in chronic hepatitis C (CH-C) patients with ACA were significantly higher than those in CH-C patients without antinuclear antibody (ANA) (12.8 +/- 1.8 vs. 8.3 +/- 4.5, P = 0.0372). The frequency of human leukocyte antigen (HLA) DR-8 in patients with HCV-related CLD seropositive for ACA was significantly higher than that in patients with CH-C seronegative for ANA (71 vs. 18%, P = 0.0108). These findings suggest that ACA is induced by chronic HCV infection in association with HLA DR-8, and that CH-C patients with ACA exhibit more severe hepatic fibrosis and inflammation than CH-C patients without ANA.

Biological autoimmunity screening in hepatitis C patients by anti-HepG2 lysate and anti-heat shock protein 70.1 autoantibodies

Viruses require viral and cellular chaperones during their life cycle and interactions of these molecules with the immune system are probable during the infection. Thus, an anti-chaperone antibody response has been firstly investigated in hepatitis C patients in this paper. A HepG2-lysate antigen (90, 79, 72, 70, 62, 54 and 48 kDa) was assayed in sera from 59 (19F/40M) chronic hepatitis C patients without cirrhosis before therapy. Forty of them were positive for anti-HepG2 lysate antigen antibodies and this test may evaluate biological autoimmunity. Hsp70.1, Hsp90 and calreticulin levels were significantly higher in this antigen than in a control HepG2 antigen. Secondly, Hsp70.1 was identified as Hsp 70 kDa protein-1 by proteomic analysis and studied as a possible antibody target. Fourteen out of 59 patients were positive for anti-Hsp70.1 antibodies that were inversely correlated with alanine aminotransferase levels, the Metavir activity index and viraemia. Finally, for comparative purposes, 50 sera from systemic lupus erythematosus (SLE) patients have been tested: eight and 41 of them were positive for anti-Hsp70.1 and anti-HepG2 lysate antigen antibodies, respectively. Therefore, anti-Hsp70.1 autoantibodies may be produced and can partially lead to biological autoimmunity in chronic hepatitis C patients.

Chronic hepatitis C virus infection: Prevalence of extrahepatic manifestations and association with cryoglobulinemia in Bulgarian patients

AIM: To assess the prevalence of extrahepatic manifestations in Bulgarian patients with chronic hepatitis C virus (HCV) infection and identify the clinical and biological manifestations associated with cryoglobulinemia.

METHODS: The medical records of 136 chronically infected HCV patients were reviewed to assess the prevalence of extrahepatic manifestations. Association between cryoglobulin-positivity and other manifestations were identified using χ² and Fisher’s exact test. Risk factors for the presence of extrahepatic manifestations were assessed by logistic regression analysis.

RESULTS: Seventy six percent (104/136) of the patients had at least one extrahepatic manifestation. Clinical manifestations included fatigue (59.6%), kidney impairment (25.0%), type 2 diabetes (22.8%), paresthesia (19.9%), arthralgia (18.4%), palpable purpura (17.6%), lymphadenopathy (16.2%), pulmonary fibrosis (15.4%), thyroid dysfunction (14.7%), Raynaud’s phenomenon (11.8%), B-cell lymphoma (8.8%), sicca syndrome (6.6%), and lichen planus (5.9%). The biological manifestations included cryoglobulin production (37.5%), thrombocytopenia (31.6%), and autoantibodies: anti-nuclear (18.4%), anti-smooth muscle (16.9%), anti-neutrophil cytoplasm (13.2%) and anti-cardiolipin (8.8%). All extrahepatic manifestations showed an association with cryoglobulin-positivity, with the exception of thyroid dysfunction, sicca syndrome, and lichen planus. Risks factors for the presence of extrahepatic manifestations (univariate analysis) were: age ≥ 60 years, female gender, virus transmission by blood transfusions, longstanding infection (≥ 20 years), and extensive liver fibrosis. The most significant risks factors (multivariate analysis) were longstanding infection and extensive liver fibrosis.

CONCLUSION: We observed a high prevalence of extrahepatic manifestations in patients with chronic HCV infection. Most of these manifestations were associated with impaired lymphoproliferation and cryoglobulin production. Longstanding infection and extensive liver fibrosis were significant risk factors for the presence of extrahepatic manifestations in HCV patients.

Cross-reactivity of antibody against SARS-coronavirus nucleocapsid protein with IL-11

Infection of SARS-associated coronavirus (SARS-CoV) induced a strong anti-nucleocapsid (anti-N) antibody response. However, the pathophysiological significance of the anti-N antibodies in SARS pathogenesis is largely unknown. To profile the anti-N antibodies, a phage-displayed scFv library was prepared from mice immunized with heat-inactivated SARS-CoV-infected Vero E6 cell lysate. Specific anti-N scFvs were isolated by panning against a recombinant nucleocapsid protein and reactivity was confirmed with phage-ELISA. Sequence analysis indicated that two of the isolated anti-N scFv clones were identical and displayed a high homology with an scFv specific for interleukin 11 (IL-11), an anti-inflammatory cytokine derived from bone marrow stroma cells. In a neutralization assay, IL-11-induced STAT 3 phosphorylation in rat intestinal epithelial IEC-18 cells was completely suppressed by the anti-N scFv clone L9N01.

Extrahepatic manifestations in patients with chronic hepatitis C virus infection

PURPOSE OF REVIEW

Chronic hepatitis C virus infection often has autoimmune clinical and analytic features. This review analyzes recent data on the close association of chronic hepatitis C virus infection with autoimmune and lymphoproliferative processes.

RECENT FINDINGS

Hepatitis C virus infection has been associated with both organ-specific (thyroiditis, diabetes) and systemic autoimmune diseases. Experimental, virologic, and clinical evidence has demonstrated a close association between hepatitis C virus infection and Sjögren syndrome, with hepatitis C virus-associated Sjögren syndrome being indistinguishable in most cases from the primary form. With respect to rheumatoid arthritis, patients with hepatitis C virus-related polyarthritis and positive rheumatoid factor may fulfill the classification criteria for rheumatoid arthritis. Hepatitis C virus has also been associated with an atypical presentation of antiphospholipid syndrome, as well as with the development of sarcoidosis. A higher prevalence of hematologic processes in patients with hepatitis C virus infection has recently been reported, including cytopenias and lymphoproliferative disorders. Recent data are available on the use of new immunosuppressive and biologic agents (mainly mycophenolate mofetil, anti-tumor necrosis factor agents, and rituximab) in patients with hepatitis C virus infection and autoimmune or lymphoproliferative manifestations.

SUMMARY

There is increasing evidence of a close association of hepatitis C virus infection with autoimmune and hematologic processes. The sialotropism of hepatitis C virus may explain the close association with Sjögren syndrome, and its lymphotropism links the virus to cryoglobulinemia, autoimmune cytopenias, and lymphoma. The substantial overlap between cryoglobulinemic features and the classification criteria for some systemic autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, and polyarteritis nodosa) make the differentiation between mimicking and coexistence difficult.

Host genetic determinants in hepatitis C virus infection

In addition to viral and environmental/behavioural factors, host genetic diversity is believed to contribute to the spectrum of clinical outcomes in hepatitis C virus (HCV) infection. This paper reviews the literature with respect to studies of host genetic determinants of HCV outcome and attempts to highlight trends and synthesise findings. With respect to the susceptibility to HCV infection, several studies have replicated associations of the HLA class II alleles DQB1(*)0301 and DRB1(*)11 with self-limiting infection predominantly in Caucasian populations. Meta-analyses yielded summary estimates of 3.0 (95% CI: 1.8-4.8) and 2.5 (95% CI: 1.7-3.7) for the effects of DQB1(*)0301 and DRB1(*)11 on self-limiting HCV, respectively. Studies of genetics and the response to interferon-based therapies have largely concerned single-nucleotide polymorphisms and have been inconsistent. Regarding studies of genetics and the progression of HCV-related disease, there is a trend with DRB1(*)11 alleles and less severe disease. Studies of extrahepatic manifestations of chronic HCV have shown an association between DQB1(*)11 and DR3 with the formation of cryoglobulins. Some important initial observations have been made with respect to genetic determinants of HCV outcome. Replication studies are needed for many of these associations, as well as biological data on the function of many of these polymorphisms.