Prevalence of autoantibodies and the risk of autoimmune thyroid disease in children with chronic hepatitis C virus infection treated with interferon-α

Hepatitis C in 2020: A North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper

In 1989, a collaboration between the Centers for Disease Control (CDC) and a California biotechnology company identified the hepatitis C virus (HCV, formerly known as non-A, non-B hepatitis virus) as the causative agent in the epidemic of silent posttransfusion hepatitis resulting in cirrhosis. We now know that, the HCV genome is a 9.6 kb positive, single-stranded RNA. A single open reading frame encodes a 3011 amino acid residue polyprotein that undergoes proteolysis to yield 10 individual gene products, consisting of 3 structural proteins (core and envelope glycoproteins E1 and E2) and 7 nonstructural (NS) proteins (p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B), which participate in posttranslational proteolytic processing and replication of HCV genetic material. Less than 25 years later, a new class of medications, known as direct-acting antivirals (DAAs) which target these proteins, were introduced to treat HCV infection. These highly effective antiviral agents are now approved for use in children as young as 3 years of age and have demonstrated sustained virologic responses exceeding 90% in most genotypes. Although tremendous scientific progress has been made, the incidence of acute HCV infections has increased by 4-fold since 2005, compounded in the last decade by a surge in opioid and intravenous drug use. Unfortunately, awareness of this deadly hepatotropic virus among members of the lay public remains limited. Patient education, advocacy, and counseling must, therefore, complement the availability of curative treatments against HCV infection if this virus is to be eradicated.

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.

Vertically acquired hepatitis C virus infection: Correlates of transmission and disease progression

The worldwide prevalence of hepatitis C virus (HCV) infection in children is 0.05%-0.4% in developed countries and 2%-5% in resource-limited settings, where inadequately tested blood products or un-sterile medical injections still remain important routes of infection. After the screening of blood donors, mother-to-child transmission (MTCT) of HCV has become the leading cause of pediatric infection, at a rate of 5%. Maternal HIV co-infection is a significant risk factor for MTCT and anti-HIV therapy during pregnancy seemingly can reduce the transmission rate of both viruses. Conversely, a high maternal viral load is an important, but not preventable risk factor, because at present no anti-HCV treatment can be administered to pregnant women to block viral replication. Caution is needed in adopting obstetric procedures, such as amniocentesis or internal fetal monitoring, that can favor fetal exposure to HCV contaminated maternal blood, though evidence is lacking on the real risk of single obstetric practices. Mode of delivery and type of feeding do not represent significant risk factors for MTCT. Therefore, there is no reason to offer elective caesarean section or discourage breast-feeding to HCV infected parturients. Information on the natural history of vertical HCV infection is limited. The primary infection is asymptomatic in infants. At least one quarter of infected children shows a spontaneous viral clearance (SVC) that usually occurs within 6 years of life. IL-28B polymorphims and genotype 3 infection have been associated with greater chances of SVC. In general, HCV progression is mild or moderate in children with chronic infection who grow regularly, though cases with marked liver fibrosis or hepatic failure have been described. Non-organ specific autoantibodies and cryoglobulins are frequently found in children with chronic infection, but autoimmune diseases or HCV associated extrahepatic manifestations are rare.

Natural history of vertically acquired HCV infection and associated autoimmune phenomena

The natural history of vertically acquired HCV infection is ill defined. The aim of this study was to outline the natural course of vertical HCV infection in a cohort of untreated children, including rate of spontaneous viral clearance, frequency and features of HCV-related autoimmune disorders. Children with vertical HCV infection were prospectively followed from the first month of life with regular clinical and laboratory assessments. Statistical analysis was performed using Prism 5.0. Forty-five children (median age 12 years, interquartile range 6.9-15.5) were studied. Genotype 1 was predominant (53.3 %). Spontaneous viral clearance was achieved by 12 patients (26.7 %) and associated with genotype 3. Alanine-amino-transferase levels were increased in most children in the first 2 years of life with higher values in those who later cleared the infection. All children were asymptomatic for liver disease. Transient elastography (32 patients) showed mild or moderate fibrosis in nine and two cases, respectively. Non-organ-specific autoantibodies were detected in 24 children (53.3 %) independently of viremia; of these, one developed type-1 diabetes. Cryoglobulinemia was associated with genotype 1 infection and found in 15 subjects (33.3 %): two had low C4 levels and persistent proteinuria.

CONCLUSIONS

Vertically acquired HCV infection may result in spontaneous clearance in up to 27 % of children. Resolution of infection is higher with genotype 3, usually occurs in preschool age and persists over time. Chronic infection is generally asymptomatic, although hepatomegaly and mild fibrosis may develop. Autoantibodies and cryoglobulins are frequent, whereas the associated clinical manifestations are rare.

Frequency of thyroid dysfunctions during interferon alpha treatment of single and combination therapy in hepatitis C virus-infected patients: a systematic review based analysis

BACKGROUND

Thyroid dysfunction is the commonest endocrinopathy associated with HCV infection due to interferon-based treatment. This comprehensive and systematic review presents the available evidence for newly developed thyroid antibodies and dysfunctions during interferon treatment (both single and combination) in HCV patients.

METHODOLOGY/PRINCIPAL FINDINGS

This systematic review was conducted in accordance with the PRISMA guidelines. The data generated were used to analyze the risk for thyroid dysfunctions during interferon (IFN) treatment in HCV patients. There was a wide range in the incidence of newly developed thyroid dysfunctions and thyroid antibodies in HCV patients during IFN treatment (both single and combination). The wide range of incidence also denoted the possibility of factors other than IFN treatment for thyroid-related abnormalities in HCV patients. These other factors include HCV viral factors, genetic predisposition, environmental factors, and patho-physiological factors. Variations in IFN dosage, treatment duration of IFN, definition/criteria followed in each study for thyroid dysfunction and irregular thyroid function testing during treatment in different studies influence the outcome of the single studies and jeopardise the validity of a pooled risk estimate of side effects of thyroid dysfunction. Importantly, reports differ as to whether the thyroid-related side effects disappear totally after withdrawal of the IFN treatment.

CONCLUSIONS/SIGNIFICANCE

The present review shows that there is a wide range in the incidence of newly developed thyroid dysfunctions and thyroid antibodies in IFN treated HCV patients. This is a comprehensive attempt to collate relevant data from 56 publications across several nations about IFN (both mono and combination therapy) related thyroid dysfunction among HCV patients. The role of each factor in causing thyroid dysfunctions in HCV patients treated with IFN should be analyzed in detail in future studies, for a better understanding of the problem and sounder clinical management of the disease.

Study of non-organ-specific antibodies in children with genotype 4 chronic hepatitis C

BACKGROUND/AIM

Adult studies established a relationship between hepatitis C virus (HCV) infection and the presence of non-organ-specific antibodies (NOSAs). Most studies were carried out on genotypes 1 and 2. Only a few studies addressed that issue in pediatrics. No studies have been carried out on autoimmunity and genotype 4 in children. We aim to investigate NOSAs in 80 Egyptian children with chronic HCV infection along with studying the underlying genotype of HCV, and correlating autoimmunity with the epidemiological, clinical, biochemical, and virological features.

MATERIALS AND METHODS

HCV-RNA was assayed by the polymerase chain reaction and viral genotypes were determined. NOSAs were measured and liver biopsies were taken for histopathological examination.

RESULTS

Genotype 4 was the only detected genotype in the included 80 patients. Anti-smooth muscle antibodies (ASMA) were the only detected antibodies in 32 (40%) patients, always with V specificity (vessels only) at titers ranging from 1:20 and 1:160. Anti-nuclear antibodies (ANA) and liver-kidney microsomal antibodies-1 (LKMA-1) were not detected in any of our patients. Epidemiologic and clinical features did not significantly differ between autoantibody-positive and -negative patients. Among biochemical features, significantly high levels of total bilirubin, albumin, immunoglobulins, alkaline phosphatase, and gamma-glutamyl transpeptidase were found in the antibody-positive group.

CONCLUSION

Genotype 4 HCV is the prevailing genotype in Egyptian children with chronic HCV infection. A consistent proportion of these children with chronic HCV infection circulate non-organ-specific autoantibodies. The prevalence of ASMA and the absence of ANA and LKMA-1 might be related to the unique situation in Egypt with unique prevalence of genotype 4. More studies are warranted on larger pediatric population to validate these findings.

Thyroid dysfunction in chinese patients with chronic hepatitis C treated with interferon alpha: incidence, long-term outcome and predictive factors

BACKGROUND

Thyroid dysfunction (TD) represents an extra-hepatic manifestation of chronic hepatitis C (CHC) and it may also be a side effect of interferon-alpha (IFN-α) based treatment. However, previous studies have shown a wide variation in the incidence of TD in patients with CHC. Furthermore, the long-term outcomes and the predictive factors of TD in patients who receive IFN-α based treatment have still not been fully studied.

OBJECTIVES

The purpose of this study was to describe the incidence and long-term outcomes of TD in Chinese patients with CHC receiving IFN-αbased treatment. We also aimed to identify the predictive factors of TD associated with this type of therapy.

PATIENTS AND METHODS

A retrospective case-series study of 592 consecutive CHC patients with normal baseline thyroid functions, who received IFN-αbased therapy, was performed. Thyroid function was assessed at baseline and every three months during treatment, as well as in the follow-up after cessation of therapy. The incidence and long-term outcomes of TD were observed. The prevalence of pretreatment thyroid peroxidase antibodies (TPOAb) were assayed in a sex- and age-matched nested case-control study. Multivariable stepwise regression analysis was used to explore the independent effects of the baseline factors, on the incidence of TD.

RESULTS

At the end of the IFN-αbased therapy, 68 patients (11.5%) in the study had developed TD, 58 patients (85.3%) presented with subclinical TD, and only 10 patients (14.7%) developed overt thyroiditis. The thyroid function of 46 patients (67.8%) spontaneously returned to normal in the six months of follow-up and only three patients (4.4%) had persistent overt TD symptoms after the 24 month follow-up period. Multivariate stepwise analysis suggested that gender and pretreatment TPOAb were the independent factors related to the incidence of TD. Both female patients (OR, 4.31; 95%CI, 2.06-7.31; P = 1.26×10-4) and participants with a positive pretreatment TPOAb (OR = 3.9, 95%CI, 1.72-8.54, P = 0.008) had an increased risk for the development of TD.

CONCLUSIONS

The incidence of TD in Chinese patients with CHC during IFN-αbased therapy was 11.5%, the majority of which was subclinical, while only a very small group had long-term overt TD requiring ongoing medical therapy. Female gender and pretreatment TPOAb positivity are risk factors for the development of TD during IFN-αbased therapy.

Autoimmunity and extrahepatic manifestations in treatment-naïve children with chronic hepatitis C virus infection

Hepatitis C virus (HCV) infection has been associated with autoimmunity and extrahepatic manifestations in adults. Few data are available on these topics in children. Nonorgan specific auto-antibodies development is part of the natural course of chronic hepatitis C in children. Smooth muscle autoantibody is the most common autoantibody found, while liver-kidney microsomal type-1 antibody positivity is the most peculiar autoimmune feature of children with HCV infection. The clinical significance of non-organ specific autoantibodies in the course of paediatric chronic hepatitis C is still debated. Autoantibody positivity can be considered neutral for most patients, while it can be associated with negative connotations for others, especially those positive for liver-kidney microsomal type-1 autoantibody. Subclinical hypothyroidism but not autoimmune thyroiditis has been demonstrated in HCV infection in children, while only few cases of HCV-associated membranoproliferative glomerulonephritis have been described. Single reports are available in the literature reporting the anecdotal association between chronic hepatitis C and other extrahepatic manifestations such as myopathy and opsoclonus-myoclonus syndrome. Despite the low incidence of extrahepatic manifestations of chronic hepatitis C in children, overall, available data suggest a careful monitoring.

The liver-cytokine-brain circuit in interferon-based treatment of patients with chronic viral hepatitis

Psychiatric symptoms are commonly identified in patients with viral hepatitis. They may have been present prior to the onset of disease and may include symptoms related to addiction issues. Furthermore, the virus and antiviral therapy, in particular interferon, may induce or modify psychiatric symptoms. Recent data support chronic hepatitis C replication in the brain and subsequent changes of cerebral metabolite spectra and magnetic resonance alterations. In chronic viral hepatitis and in other chronic inflammatory diseases, an alteration of the neuro-endocrine-immune system response has been observed. Catecholamines and glucocorticoids modulate this immune/inflammatory reaction. Psychiatric assessment and monitoring before, during and after antiviral therapy can identify patients whose psychiatric symptoms preclude therapy, and those who may benefit from psychopharmacological therapy and counselling, thereby improving therapeutic results. This review will discuss current insights into the complex interplay between cytokines, liver and brain in chronic viral hepatitis closely associated with psychiatric issues, especially in the case of antiviral therapy, with the aim of indicating future research and possible treatments.

Re-treatment of children with chronic hepatitis C who did not respond to interferon-alpha treatment

BACKGROUND

Many patients with chronic hepatitis C do not respond to antiviral treatment. In adult patients the re-treatment of these patients has been extensively investigated. Because the response to re-treatment in children is not well defined we evaluated the efficacy and safety of interferon (IFN)-alpha plus ribavirin in patients who have failed to respond to previous treatment.

PATIENTS AND METHODS

In an open-label, uncontrolled study, 18 chronically infected children were investigated. Fifteen children had been treated with IFN-alpha plus ribavirin and 3 patients with IFN-alpha alone. Fourteen patients were nonresponders; 4 experienced viral breakthrough during treatment and/or relapse after treatment. Patients received IFN-alpha 3 times per week subcutaneously plus ribavirin for 48 weeks. Sixteen patients were infected with hepatitis C virus (HCV) genotype 1, 2 with genotype 4, and 1 with genotype 3 and co-infection with hepatitis B.

RESULTS

Four patients showed early viral response to therapy and became HCV-RNA negative after 12 weeks. Sustained viral response (HCV-RNA negative 6 months after end of treatment) was documented in 2 of them. These 2 patients belonged to the group of 4 children who relapsed or experienced a viral breakthrough during previous treatment. None of the 14 patients with prior nonresponse had sustained viral response.

CONCLUSIONS

Re-treatment with IFN-alpha plus ribavirin may be useful in children who relapsed in a previous antiviral treatment but seems not to be useful in nonresponders. These results are in line with studies from adult patients and should be therefore encouraged to provide a second chance for healing in a subgroup of patients.

Chronic hepatitis C virus infection in children

The importance of hepatitis C viral infection in the health care of children has grown in recent decades. More is now known about the epidemiology of this infection in children and the progression of disease in the pediatric age group, and the treatment options are increasing. In this review, we update readers on the state of our understanding of hepatitis C infection in children, provide the current recommendations for monitoring and treatment, and discuss emerging therapies.

Managing pediatric hepatitis C: current and emerging treatment options

Since 1992, the maternal–fetal route of transmission has become the dominant route for acquisition of hepatitis C (HCV) infection by children. With increasing knowledge of antiviral treatment for HCV infection, the main goal of therapy is to achieve a sustained virological response (SVR) as defined by undetectable serum HCV RNA by polymerase chain reaction assay six months after cessation of therapy. In young children, interferon therapy is more effective than in adults with chronic HCV infection (CHC). Although children clearly have a milder degree of liver pathology, data have indicated that hepatic inflammation from HCV infection can progress to fibrosis or cirrhosis in children. Hepatocellular carcinoma has been reported in adolescents with CHC. In this article, recent improvements in therapy of children with CHC and in the clinical development of new emerging drugs with potential use in children will be reviewed.

Hepatitis C-associated rheumatic disorders

Hepatitis C virus (HCV) is an important causative agent of liver diseases. However, HCV infection is also associated with numerous hematologic, renal, dermatologic, rheumatic, and autoimmune disorders. These include arthralgia, arthritis, vasculitis, sicca syndrome, myalgia, and fibromyalgia. The purpose of this article is to review the prevalence and spectrum of rheumatic disorders and autoimmune phenomena in HCV-infected patients. It evaluates and current treatment options including nonsteroidal anti-inflammatory drugs, low-dose corticosteroids, hydroxychloroquine, methotrexate, penicillamine, combined antiviral therapy, cyclosporin A, anti-TNF-a agents, and rituximab. It concludes that larger, controlled studies are needed to establish further the treatment indications, efficacy, and safety of these agents.

Thyroid function and anti-thyroid autoantibodies in untreated children with vertically acquired chronic hepatitis C virus infection

OBJECTIVE

The reported data on thyroid function and anti-thyroid autoantibodies in adults with untreated hepatitis C virus (HCV) infection are controversial. Data are scarce for HCV-infected children, and only in those treated with interferon-alpha (IFN-alpha). We investigated thyroid function and anti-thyroid autoantibodies in a cohort of untreated children with vertically acquired, chronic, HCV infection.

DESIGN AND PATIENTS

FT4 and TSH serum levels (measured by immunometric assays) and anti-thyroglobulin (TgA) and anti-thyroperoxidase (TPOA) antibodies (evaluated by fluorescence enzymatic immunoassays) were studied in 36 consecutive HCV-infected children and 150 age- and sex-matched controls. The prevalence of thyroid involvement was also related to family history of autoimmune disease, distribution of HCV genotypes, and duration and activity of HCV infection.

RESULTS

Four out of 36 (11.1%) HCV-infected children and 4/150 controls (2.7%) showed subclinical hypothyroidism [P = 0.04; relative risk (RR) 4.56, 95% confidence interval (CI) 1.08-19.21]. None of these had anti-thyroid autoantibodies. Two out of 36 (5.6%) HCV-infected children and 1/150 (0.7%) controls had increased TgA values with normal levels of TSH (P > 0.05). Subclinical hypothyroidism and anti-thyroid autoantibodies were not related to family history of autoimmune disease, duration of infection, HCV viral load, liver function or different HCV genotype distribution, but seemed to be related to the presence of active HCV infection.

CONCLUSIONS

Our data suggest a role for HCV infection in the development of nonautoimmune thyroid disease in untreated HCV-infected children, confirming previous studies in adults. Clinicians should be aware of thyroid dysfunction even in untreated children.