Thyroid Involvement in Hepatitis C Virus-Infected Patients with/without Mixed Cryoglobulinemia

The Potential Role of Virus Infection in the Progression of Thyroid Cancer

Multiple factors have engaged in the progression of thyroid cancer (TC). Recent studies have shown that viral infection can be a critical factor in the pathogenesis of TC. Viruses, such as Epstein-Barr virus (EBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), may play an essential role in the occurrence, development, and even prognosis in TC. This review mainly explored the potential role of viral infection in the progress of TC. The possible mechanisms could be recognizing the host cell, binding to the receptors, affecting oncogenes levels, releasing viral products to shape a beneficial environment, interacting with immune cells to induce immune evasion, and altering the pituitary-thyroid axis. Thus, comprehensive knowledge may provide insights into finding molecular targets for diagnosing and treating virus-related TC.

Levothyroxine and Non-alcoholic Fatty Liver Disease: A Mini Review

Levothyroxine or l-thyroxine is artificially manufactured thyroxine, which is used as a drug to treat underactive thyroid conditions in humans. The drug, levothyroxine, is consumed daily in a prescribed dose to replace the missing thyroid hormone thyroxine in an individual with an underactive thyroid, and it helps to maintain normal physiological conditions. Though it is a life-maintaining drug, it replaces the missing thyroid hormone and performs the necessary daily metabolic functions in our body. Like all other allopathic drugs, it comes with certain side effects, which include joint pain, cramps in muscle, weight gain/loss, hair loss, etc. The thyroid hormone, thyroxine, is known to mobilize fat in our body, including the ones from the hepatic system. An underactive thyroid may cause an accumulation of fat in the liver, leading to a fatty liver, which is clinically termed Non-Alcoholic Fatty Liver Disease (NAFLD). The correlation between hypothyroidism and NAFLD is now well-studied and recognized. As levothyroxine performs the functions of the missing thyroxine, it is anticipated, based on certain preliminary studies, that the drug helps to mobilize hepatic fat and thus may have a crucial role in mitigating the condition of NAFDL.

Molecular mimicry and autoimmunity in the time of COVID-19

Infectious diseases are commonly implicated as potential initiators of autoimmune diseases (ADs) and represent the most commonly known factor in the development of autoimmunity in susceptible individuals. Epidemiological data and animal studies on multiple ADs suggest that molecular mimicry is one of the likely mechanisms for the loss of peripheral tolerance and the development of clinical disease. Besides molecular mimicry, other mechanisms such as defects in central tolerance, nonspecific bystander activation, epitope-determinant spreading, and/or constant antigenic stimuli, may also contribute for breach of tolerance and to the development of ADs. Linear peptide homology is not the only mechanism by which molecular mimicry is established. Peptide modeling (i.e., 3D structure), molecular docking analyses, and affinity estimation for HLAs are emerging as critical strategies when studying the links of molecular mimicry in the development of autoimmunity. In the current pandemic, several reports have confirmed an influence of SARS-CoV-2 on subsequent autoimmunity. Bioinformatic and experimental evidence support the potential role of molecular mimicry. Peptide dimensional analysis requires more research and will be increasingly important for designing and distributing vaccines and better understanding the role of environmental factors related to autoimmunity.

Partners in crime: Autoantibodies complicit in COVID-19 pathogenesis

Autoantibodies (AABs) play a critical role in the pathogenesis of autoimmune diseases (AIDs) and serve as a diagnostic and prognostic tool in assessing these complex disorders. Viral infections have long been recognized as a principal environmental factor affecting the production of AABs and the development of autoimmunity. COVID-19 has primarily been considered a hyperinflammatory syndrome triggered by a cytokine storm. In the following, the role of maladaptive B cell response and AABs became more apparent in COVID-19 pathogenesis. The current review will primarily focus on the role of extrafollicular B cell response, Toll-like receptor-7 (TLR-7) activation, and neutrophil extracellular traps (NETs) formation in the development of AABs following SARS-CoV-2 infection. In the following, this review will clarify how these AABs dysregulate immune response to SARS-CoV-2 by disrupting cytokine function and triggering neutrophil hyper-reactivity. Finally, the pathologic effects of these AABs will be further described in COVID-19 associate clinical manifestations, including venous and arterial thrombosis, a multisystem inflammatory syndrome in children (MIS-C), acute respiratory distress syndrome (ARDS), and recently described post-acute sequelae of COVID-19 (PASC) or long-COVID.

Viruses and Endocrine Diseases

Viral infections have been frequently associated with physiological and pathological changes in the endocrine system for many years. The numerous early and late endocrine complications reported during the current pandemic of coronavirus disease 2019 (COVID-19) reinforce the relevance of improving our understanding of the impact of viral infections on the endocrine system. Several viruses have been shown to infect endocrine cells and induce endocrine system disturbances through the direct damage of these cells or through indirect mechanisms, especially the activation of the host antiviral immune response, which may lead to the development of local or systemic inflammation or organ-specific autoimmunity. In addition, endocrine disorders may also affect susceptibility to viral infections since endocrine hormones have immunoregulatory functions. This review provides a brief overview of the impact of viral infections on the human endocrine system in order to provide new avenues for the control of endocrine diseases.

COVID-19 AND THE THYROID FUNCTION IN PATIENTS WITH HCV- ASSOCIATED HEPATOCELLULAR CARCINOMA

Context

COVID-19 is more than a respiratory infection, with deep implications regarding multiple systems and organs. Thyroid damage is frequent in COVID-19 and may overlap previous HCV or HCC associated diseases.

Objective

The objective of this study is to determine the effects of COVID-19 in patients with HCV associated HCC and thyroid comorbidities.

Design

We performed a retrospective study of the thyroid function tests and autoantibodies in patients with HCV-associated HCC prior and during COVID-19.

Subjects and Methods

We included 52 consecutive patients with HCV-associated HCC and documented thyroid disease, diagnosed with COVID -19 between April and October 2020. Serum values of thyroid-stimulating hormone, free T3, free T4, anti-thyroglobulin antibodies and anti-thyroid peroxydase antibodies were determined and compared to baseline levels.

Results

At baseline, 44 patients had positive antithyroid antibodies, 6 had hypothyroidism in substitution and 2 had hyperthyroidism under treatment. During COVID-19 we found an increase in serum values of antithyroid antibodies, and decreased levels of TSH, freeT3 and freeT4 levels. Specific therapies were discontinued in one patient with hyperthyroidism and 3 patients with hypothyroidism.

Conclusion

There is a significant impact of COVID-19 on the thyroid homeostasis; a long-term prognostic value for patients with HCC infected with COVID-19 required further extensive research.

Myoinositol in Autoimmune Thyroiditis

Myoinositol (Myo) is an isoform of inositol, a cyclic polyol with 6 hydroxyl groups. Myo is mainly derived from dietary intake while its endogenous production is generated from glucose by enzymatic reactions. Moreover, Myo is also synthesized de novo by catabolism of phosphatidylinositol (PI), phosphoinositides (PIP), and inositol phosphates (IP). Myo has a determinant role in thyroid function and autoimmune diseases as it regulates iodine organification and thyroid hormone biosynthesis by the formation of hydrogen peroxide (H₂O₂) in thyrocytes. Depletion of Myo that is involved in the thyroid stimulating hormone (TSH) signaling pathway, may cause the development of thyroid diseases such as hypothyroidism. TSH levels significantly decreased in patients with subclinical hypothyroidism, with or without autoimmune thyroiditis, after treatment with Myo plus Selenium (Myo+Se). In addition to TSH, antithyroid autoantibodies are reduced. This review summarizes the role of Myo in the thyroidal physiology and its role in the management of some thyroid diseases.

A Review on Extrahepatic Manifestations of Chronic Hepatitis C Virus Infection and the Impact of Direct-Acting Antiviral Therapy

Extrahepatic manifestations are a feature of chronic hepatitis C virus (HCV) infection. In the course of chronic HCV infection, about 70% of patients have one or more extrahepatic manifestations. The latter are often the first and only clinical sign of infection. Experimental and clinical data support a causal association for many extrahepatic manifestations and HCV infection, which include mixed cryoglobulinemia, non-Hodgkin lymphomas (NHL), cardiovascular disease, insulin resistance, type 2 diabetes, neurological and psychiatric disease and other rheumatic diseases. All these extrahepatic conditions influence the morbidity, quality of life and mortality of HCV-infected patients. Currently, interferon-free therapeutic regimens with direct-acting antiviral agents (DAA) offer the possibility of treatment to almost the entire infected population, irrespective of stage of cirrhosis and associated serious comorbidities, always maintaining a high efficacy and tolerability. Several studies have shown a close association between HCV clearance by DAAs and an improvement or reduction in the risk of extrahepatic manifestations. Patients with HCV after a sustained virologic response (SVR) by DAA treatment have a lower risk than non-responders of developing cryoglobulinemic vasculitis and B-cell non-Hodgkin’s lymphomas. Furthermore, the SVR by DAA also reduces the risk of acute coronary syndrome, cardiovascular disease, insulin resistance and type 2 diabetes, and it improves atherosclerosis. HCV clearance by DAA also improves the quality of life and survival of patients with chronic HCV infection with associated extrahepatic diseases. Thus, DAAs should be initiated as early as possible in HCV patients with extrahepatic manifestations.

The impact of COVID 19 infection on HCV-induced thyroid disease

CONTEXT

As we progress into the COVID-19 pandemic, it has become apparent that this infection is associated with a multitude of systemic effects, some involving the thyroid gland. The thyroid is also frequently affected in the HCV chronic infection.

OBJECTIVE

The objective of this study is to determine the effects of COVID-19 infection on the presence and severity of thyroid disorders associated with chronic HCV infection, at short and mid-term follow-up.

DESIGN

We prospectively evaluated patients with documented HCV- associated thyroid disease (with sustained virologic response after antiviral therapy).

SUBJECTS AND METHODS

The study group consisted of 42 patients with HCV- associated thyroid disease, diagnosed with COVID -19 infection between April and October 2020. We determined serum values of thyroid-stimulating hormone, freeT3, free T4, anti-thyroglobulin antibodies and anti-thyroid peroxidase antibodies at one and three months after resolution of infection and compared them to the baseline characteristics of the patient. We also evaluated the changes in thyroid substitution treatments or antithyroid drugs.

RESULTS

At baseline, out of the 42 patients, 5 presented hypothyroidism under levothyroxine substitution therapy, while 2 presented hyperthyroidism under methimazole therapy; 37 patients had positive antithyroid antibodies. At one month follow-up, we note an increase in serum values of antibodies, with a decrease in TSH, freeT3 and freeT4 levels, correlated with the severity of COVID-19 infection. Two patients required discontinuation of levothyroxine. At 3 months follow-up, lower levels of antithyroid antibodies were recorded, with an increase in TSH levels. No medication doses were adjusted at this time.

CONCLUSION

Among the systemic effects of COVID-19, the impact of thyroid dysfunction should not be underestimated, especially in the presence of pre-existing conditions, such as HCV infection.

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.

Possible Association of Elevated Plasma Levels of Growth Arrest-Specific Protein 6 and the Soluble Form of Tyrosine Kinase Receptor Axl with Low Hepatitis C Viral Load in Patients with Type 2 Diabetes Mellitus

This study aimed to investigate the plasma levels of Gas6 and soluble Axl (sAxl) in patients with chronic hepatitis C virus (HCV) infection with and without type 2 diabetes mellitus (T2DM). The study involved four groups; 50 patients with chronic HCV, 50 patients with T2DM, 50 patients with chronic HCV and T2DM, and 31 age- and sex-matched healthy controls. T2DM was diagnosed according to American Diabetes Association criteria, HCV antibodies were detected by enzyme-linked immunosorbent assays (ELISA) and confirmed by real-time-polymerase chain reaction. Plasma Gas6 and sAxl levels were assayed in all groups by ELISA. Significant low levels of GAS 6 in HCV/T2DM group versus HCV group were detected (7.92 ± 5.18 vs. 16.09 ± 7.36, respectively, p = 0.000), but higher than T2DM and control groups (p ≥ 0.05), although nonsignificant. HCV load was higher in the HCV group than the HCV/T2DM group (1,888,300 ± 5,595,070 vs. 1,417,900 ± 4,066,460 copies/mL, respectively, p = 0.632). Among HCV group, significant positive correlations were detected between Gas6 and sAxl levels with HCV viral load (r = 0.48, p = 0.000 and r = 0.43, p = 0.002, respectively), while among HCV/T2DM group, significant negative correlations were detected (r = -0.29, p = 0.04 and r = -0.34, p = 0.014, respectively). Significant negative correlations were detected between Gas6/sAxl levels and glycated hemoglobin (r = -0.36, p = 0.01 and r = -0.4, p = 0.003, respectively) in T2DM despite the positive correlations detected in HCV/T2DM (r = 0.27, p = 0.053 and r = 0.55, p = 0.000, respectively). In conclusion, Gas6/Axl system in combined HCV/T2DM diseases may affect the pathogenesis and can alter the biomarkers and complications of both diseases in a manner that differs from a solitary disease.

Graves' disease: Epidemiology, genetic and environmental risk factors and viruses

Graves' disease (GD) is the most common cause of hyperthyroidism in developed Countries. It is more common between 30 and 60 years; 5-10 times more frequent in women. The genetic predisposition accounts for 79% of the risk for GD, while environmental factors for 21%. About 70% of genes associated with autoimmune thyroid disorders (AITD) are implicated in T-cell function. Among GD endogenous factors, estrogens, X-inactivation and microchimerism are important. Among environmental risk factors, smoking, iodine excess, selenium and vitamin D deficiency, and the occupational exposure to Agent Orange have been associated with GD. Many studies showed that HCV is associated with thyroid autoimmunity and hypothyroidism, in patients with chronic HCV hepatitis (CHC); a significant link has been shown also between HCV-related mixed cryoglobulinemia and risk for GD. Moreover, IFN-α-treated CHC patients develop GD more frequently. Novel studies are needed about possible risk factors to reduce the occurence of GD in West Countries.

Risk of New-Onset Atrial Fibrillation Among Asian Chronic Hepatitis C Virus Carriers: A Nationwide Population-Based Cohort Study

Background Hepatitis C virus (HCV) infection not only links closely to systemic inflammation but also has numerous extrahepatic manifestations. Chronic inflammation also increases the risk of new-onset atrial fibrillation (AF). However, little is known regarding the clinical association between HCV infection and new-onset AF. Methods and Results We conducted a population-based cohort study using Taiwan's National Health Insurance Research Database during 1997 to 2013. A total of 11 771 HCV-infected patients were included in this study, and each of them was matched in a ratio of 1:4. Because of higher mortality among HCV cohorts, we used both Cox proportional hazard regression and competing risk regression models to compute the hazard ratios accompanying 95% CIs after adjustment for relevant confounder. The results demonstrated that the patients with chronic HCV infection had significantly higher incidence rate (332.0 versus 265.8 in 100 000 person-years, P<0.0001) of new-onset AF compared with the non-HCV population. The adjusted hazard ratio of HCV for new-onset AF was 1.32 (95% CI, 1.20-1.44; P<0.0001) and 1.20 (95% CI, 1.10-1.31; P=0.0001) while calculated with Cox proportional hazard regression model and competing risk model, respectively. Intriguingly, we observed that the patients with HCV treated with antiviral agents had significantly lower incidental AF than those without anti-HCV treatment (1.2% versus 6.0%; P<0.0001). Conclusions Chronic HCV infection was associated with an increased risk of incidental AF probably through sharing common pathology of chronic inflammation. Furthermore, a well-designed study is needed to clarify whether anti-HCV therapy can provide protection against the occurrence of AF.

Viruses and Autoimmunity: A Review on the Potential Interaction and Molecular Mechanisms

For a long time, viruses have been shown to modify the clinical picture of several autoimmune diseases, including type 1 diabetes (T1D), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren’s syndrome (SS), herpetic stromal keratitis (HSK), celiac disease (CD), and multiple sclerosis (MS). Best examples of viral infections that have been proposed to modulate the induction and development of autoimmune diseases are the infections with enteric viruses such as Coxsackie B virus (CVB) and rotavirus, as well as influenza A viruses (IAV), and herpesviruses. Other viruses that have been studied in this context include, measles, mumps, and rubella. Epidemiological studies in humans and experimental studies in animal have shown that viral infections can induce or protect from autoimmunopathologies depending on several factors including genetic background, host-elicited immune responses, type of virus strain, viral load, and the onset time of infection. Still, data delineating the clear mechanistic interaction between the virus and the immune system to induce autoreactivity are scarce. Available data indicate that viral-induced autoimmunity can be activated through multiple mechanisms including molecular mimicry, epitope spreading, bystander activation, and immortalization of infected B cells. Contrarily, the protective effects can be achieved via regulatory immune responses which lead to the suppression of autoimmune phenomena. Therefore, a better understanding of the immune-related molecular processes in virus-induced autoimmunity is warranted. Here we provide an overview of the current understanding of viral-induced autoimmunity and the mechanisms that are associated with this phenomenon.

Bioinformatics Analysis of Quantitative PCR and Reverse Transcription PCR in Detecting HCV RNA

Objective:

This research aimed to make comparisons of sensitivity and specificity between Quantitative real Time Polymerase Chain Reaction (Q-PCR) and Reverse Transcription PCR (RT-PCR) in detecting the ribonucleic acid (RNA) expression levels of Hepatitis C Virus (HCV).

Methods:

121 patients suffering from hepatitis C and 98 healthy participants with normal liver functions were identified. The venous blood collections were carried out, were subjected to detect the expression levels of HCV RNA via Q-PCR and RT-PCR. And then, the data obtained from these above two detection methods were compared, including the sensitivity and specificity.

Results:

In terms of Q-PCR, the positive rate of HCV RNA was 72.16%, which was significantly higher when compared with 55.26% of RT-PCR. After statistical analysis, the difference between them was statistically significant (P＜0.05). Among the healthy participants, 4 cases were false positive by means of RT-PCR, there was the possibility of missed diagnosis when the samples were evaluated by Q-PCR.

Conclusion:

: The Q-PCR detection technology performed well in testing HCV, with pretty high sensitivity and specificity. Nevertheless, the false negative results obtained from Q-PCR could not be avoided. In clinical practice, these above two detection methods should be referred to, in order to avoid missed diagnosis.

Endocrine disorders associated with hepatitis C virus chronic infection

The term "HCV syndrome" encompasses several organ- and systemic pathophysiological states, which often recognize autoimmunity or neoplastic evolution in their pathophysiology, as well as chronic HCV infection as trigger. The clinical features of HCV patients are heterogenous, and may include endocrine or metabolic disorders, namely autoimmune thyroiditis, type 2 diabetes mellitus, and erectile/sexual dysfunctions. In this review, we summarize current knowledge on the endocrine/metabolic diseases associated with chronic HCV infection, focusing on the main concepts emerged in the recent literature in this field. The application of this knowledge in everyday clinical practice may be relevant, in order to reinforce a holistic vision of the patient with chronic HCV infection, stimulating in turn a multi-disciplinary approach, thus increasing the probability of early diagnosis, more effective treatments, and a better prognostic outcome.

The increasing prevalence of chronic lymphocytic thyroiditis in papillary microcarcinoma

Although the incidence of some malignancy has decreased over the recent years, this is not the case of papillary thyroid microcarcinoma (PTMC), whose incidence has increased worldwide. Most PTMC are found incidentally after histological examination of specimens from surgery for benign thyroid disease. Hashimoto's thyroiditis, whose incidence has also increased, coexists in about one in three PTMC patients. Three different mechanisms have been proposed to clarify the association between chronic lymphocytic thyroiditis and PTMC, namely tumor development/growth by: (i) TSH stimulation, (ii) expression of certain proto-oncogenes, (iii) chemokines and other molecules produced by the lymphocytic infiltrate. Whether Hashimoto's thyroiditis protects against lymph node metastasis is debated. Overall, autommune thyroiditis seems to contribute to the favorable prognosis of PTMC. Major limitations of the studies so far performed include: (i) retrospective design, (ii) limited statistical power, (iii) high risk of selection bias, (iv) and predominant Asian ethnicity of patients. Full genetic profiling of both diseases and identification of environmental factors capable to trigger them, as well as well-powered prospective studies on different ethnical groups, may help understand their causal association and why their frequencies are continuing raising.

Clinical practice: hepatitis C virus infection, cryoglobulinemia and cryoglobulinemic vasculitis

Cryoglobulins are circulating immunoglobulins that reversibly precipitate at temperatures below 37 °C. Type-II cryoglobulins consist of monoclonal IgM/polyclonal IgG immune complexes (ICs), whereas in type-III cryoglobulins both IgM and IgG are polyclonal. The clinical condition resulting from the presence of cryoglobulins in the blood is called mixed cryoglobulinemia (MC), which can be asymptomatic or manifest as cryoglobulinemic vasculitis (CV). Type-I cryoglobulins, consisting of a single monoclonal isotype, are detected in patients with lymphoproliferative disorders. It is now established that > 90% of MCs are associated with HCV infection. Clinically, the spectrum of symptoms may range in severity from occasional purpuric eruptions to life-threatening features. In addition to the development of liver cirrhosis and hepatocellular carcinoma, the possible progression of HCV-positive CV patients to B-cell non-Hodgkin lymphoma (B-NHL) has been reported. The pathogenetic role played by HCV infection in the onset of B-NHL is suggested by regression of the latter following the achievement of a sustained virologic response (SVR). For several years, interferon-α alone or combined with ribavirin has been the standard of care. However, the rates of clinical, biochemical, and virologic responses have been low, and the occurrence of relapse frequent. The addition of rituximab has resulted in a higher rate of responses. With the advent of direct-acting antiviral agents, SVR has been achieved in ~ 95% of CV patients. However, in a minority of patients, despite SVR, CV may persist or reappear over variable lengths of time from the completion of therapy. The eventual appearance of B-NHL is also possible.