Independent expression of serological markers of thyroid autoimmunity and hepatitis virus C infection in the general population: results of a community-based study in north-western Sardinia

Direct-acting antivirals used in HCV-related liver disease do not affect thyroid function and autoimmunity

PURPOSE

It is well known that interferon-α (IFN-α), used for long time as the main therapy for HCV-related disease, induces thyroid alterations, but the impact of the new direct-acting antivirals (DAAs) on thyroid is not established. Aim of this prospective study was to evaluate if DAAs therapy may induce thyroid alterations.

METHODS

A total of 113 HCV patients, subdivided at the time of the enrollment in naïve group (n = 64) and in IFN-α group (n = 49) previously treated with pegylated interferon-α and ribavirin, were evaluated for thyroid function and autoimmunity before and after 20-32 weeks of DAAs.

RESULTS

Before starting DAAs, a total of 8/113 (7.1%) patients showed Hashimoto's thyroiditis (HT) all belonging to IFN-α group (8/49, 16.3%), while no HT cases were found in the naïve group. Overall, 7/113 (6.2%) patients were hypothyroid: 3/64 (4.7%) belonging to naïve group and 4/49 (8.2%) to IFN-α group. Furthermore, a total of 8/113 patients (7.1%) showed subclinical hyperthyroidism: 2/64 (3.1%) were from naïve group and 6/49 (12.2%) from IFN-α group. Interestingly, after DAAs therapy, no new cases of HT, hypothyroidism and hyperthyroidism was found in all series, while 6/11 (54.5%) patients with non-autoimmune subclinical thyroid dysfunction became euthyroid. Finally, the only association between viral genotypes and thyroid alterations was genotype 1 and hypothyroidism.

CONCLUSIONS

This study supports evidence that DAAs have a limited or missing influence on thyroid in patients with HCV-related diseases. Moreover, it provides preliminary evidence that subclinical non-autoimmune thyroid dysfunction may improve after HCV infection resolution obtained by DAAs.

Disruption by stealth - Interference of endocrine disrupting chemicals on hormonal crosstalk with thyroid axis function in humans and other animals

Thyroid hormones (THs) are important regulators of growth, development, and homeostasis of all vertebrates. There are many environmental contaminants that are known to disrupt TH action, yet their mechanisms are only partially understood. While the effects of Endocrine Disrupting Chemicals (EDCs) are mostly studied as "hormone system silos", the present critical review highlights the complexity of EDCs interfering with TH function through their interactions with other hormonal axes involved in reproduction, stress, and energy metabolism. The impact of EDCs on components that are shared between hormone signaling pathways or intersect between pathways can thus extend beyond the molecular ramifications to cellular, physiological, behavioral, and whole-body consequences for exposed organisms. The comparatively more extensive studies conducted in mammalian models provides encouraging support for expanded investigation and highlight the paucity of data generated in other non-mammalian vertebrate classes. As greater genomics-based resources become available across vertebrate classes, better identification and delineation of EDC effects, modes of action, and identification of effective biomarkers suitable for HPT disruption is possible. EDC-derived effects are likely to cascade into a plurality of physiological effects far more complex than the few variables tested within any research studies. The field should move towards understanding a system of hormonal systems' interactions rather than maintaining hormone system silos.

High prevalence of papillary thyroid carcinoma in nodular Hashimoto's thyroiditis at the first diagnosis and during the follow-up

BACKGROUND

The association between Hashimoto's thyroiditis (HT) and papillary thyroid carcinoma (PTC) remains to be elucidated.

MATERIALS AND METHODS

A total of 484 HT patients were retrospectively subdivided into two groups: 243 without thyroid nodules, TNs (HTN-) and 241 with TNs (HTN+). Fine-needle aspiration cytology was available in 152 HTN+ patients. This group was compared to a group of 161 patients with nodular goiter (NG) without HT. Finally, 70 HTN+ and 37 NG patients underwent surgery.

RESULTS

A very high prevalence of suspicious/malignant cytology (Thy 4-5) at the first diagnosis (38/124; 31%) and during the follow-up (6/28; 22%) was found in HTN+ group. In HTN- group, 22/130 (17%) patients developed TN, but none showed malignant features during the follow-up. HTN+ patients had higher prevalence of Thy 4-5 (44/152 = 28.9%) compared to NG patients (12/161 = 7.4%, p < 0.0001). Increased independent odds ratio (OR) for malignancy was conferred by serum TSH > 1.0 μUI/ml, [OR 1.93, 95% confidence interval (CI) 1.41-2.64, p < 0.0001], male sex (OR 3.44, CI 1.48-8.02, p = 0.004) and HT (OR 3.14; CI 1.08-9.31, p < 0.05). Malignant histology (mostly PTC) was confirmed higher in HTN+ (48/70, 68.6%) compared to NG (15/37, 40.5%; p < 0.05). Higher prevalence of extrathyroidal infiltration (24/48, 50%) and vascular invasion (25/48, 52%) was found in HTN+ vs NG (2/15, 1.3% p < 0.01), (3/16, 1.8% p < 0.05), respectively.

CONCLUSIONS

This study confirms higher prevalence of suspicious/malignant cytology and PTC at histology in nodular HT compared to NG, without evidence of malignancy in non-nodular HT patients during the follow-up.

Circulating antithyroid antibodies contribute to the decrease of glomerular filtration rate in lithium-treated patients: a longitudinal study

Background

Concerns about the adverse effects of long-term treatment with lithium include reduced renal function. In the present study, we examined comorbidities which may be associated with chronic kidney disease in a cohort of patients treated with lithium for up to 41 years.

Methods

We studied 394 patients who were treated with lithium for ≥ 5 years. The potential role of comorbidities (diabetes, concurrent antihypertensive medication, treatment with l-thyroxine, and presence of antithyroid peroxidase/microsomes, anti-thyroglobulin, and/or anti-thyrotropin-receptor antibodies) was analysed. We focused on the categories of patients with an estimated glomerular filtration rate (eGFR) lower than 60 or 45 mL/min/1.73 m² as calculated from serum creatinine according to the Modification of Diet in Renal Disease Study Group. We applied multivariate regression analysis and Cox survival analysis to study the effects exerted by sex, age, duration of lithium treatment, and comorbidities using eGFR categories as the dependent variable. Kaplan–Meier curves were generated to measure the time to decline to an eGFR lower than 45 mL/min/1.73 m² in patients with positive or negative thyroid antibodies.

Results

Age was associated with a decline to an eGFR lower than 60 mL/min/1.73 m² after controlling for sex, duration of lithium treatment, and comorbidities. Circulating thyroid antibodies were associated with a decline to an eGFR lower than 45 mL/min/1.73 m².

Conclusions

The present study is the first to suggest a potential role of circulating thyroid antibodies in the severe decline of eGFR in lithium-treated patients.

The Sardinian Puzzle: Concentration of Major Psychoses and Suicide in the Same Sub-Regions Across One Century

BACKGROUND

Sardinia, the second largest Mediterranean island has long been considered a privileged observatory for the study of several medical conditions. The peculiar epidemiology of mood disorders and suicide across Sardinian sub-regions has long intrigued clinicians and researchers.

OBJECTIVE

The principal aim of the present study was to test whether the geographical distribution of suicides committed in Sardinian over the last three decades are comparable with the geographical origin of patients hospitalized up to half a century ago.

METHOD

The distribution of the municipalities of origin of the patients hospitalized in Sardinia between 1901 and 1964 for schizophrenia, bipolar disorder, and depression was reanalyzed and compared with the distribution of municipalities where suicides were committed between 1980 and 2013. Data were also analyzed by the altitude above the sea level and by the population size of the municipalities.

RESULTS

There was a significant variation of hospitalization and suicide rates across Sardinian sub-regions. The sub-regions of origin of the patients hospitalized for schizophrenia and bipolar disorder correlated with each other (P = 0.047). Both hospitalizations and suicides were more incident in municipalities with a higher altitude and a smaller population size. The incidence of hospitalizations and suicides correlated significantly with each other both at the municipality (P = 1.86 x 10-7) and at the sub-region level (P = 1.71 x 10-7).

CONCLUSION

The present study confirms the peculiar geographical distribution of major psychoses and suicide in Sardinia. The two phenomena appear to have been correlated for as long as one century.

Epidemiological burden estimates for pathologies with a nonconstant risk: an application to HCV in Italy according to age, Metavir score, and genotype: A systematic review and meta-analysis

Between western European countries, the hepatitis C virus (HCV) endemic is highest in Italy. The main objective of this paper is to estimate the endemic diffusion of hepatitis C at the national level and by geographical area, with an extrapolation at the regional level and by uniform cohorts of subjects (by sex and year of birth). The secondary objective is a stratification by gravity of the estimated statistical figures to provide an overview of possible targets of the new anti-HCV treatments.PubMed and the Cochrane Library were searched for relevant Italian populations studies regarding HCV prevalence. Random and fixed effect models were used for pooling data. To develop the epidemiological model, a meta-analysis of studies of Italian populations and the explicit consideration of the changes in the etiology of the disease in different cohorts (by year of birth) of population and the impact of effective treatments that have been introduced since the 1990s. A Markovian transition model, which is based on the distribution of HCV+ and HCV Ribonucleic Acid (RNA)+ subjects, provides a plausible assessment of the Italian situation. The Meta-analysis of Observational Studies in Epidemiology recommendations/statements were followed.In 2014, 1569,215 HCV+ subjects (95% credible interval [CrI]: 1202,630-2021,261) were estimated in Italy, with a 2.58% prevalence (95% CrI: 1.98%-3.33%). A total of 828,884 HCV RNA+ subjects (95% CrI: 615,892-1081,123), which is equal to a 1.36% prevalence (95% CrI: 1.01%-1.78%), is higher in southern Italy and the islands (1.9%) than in central-northern Italy (1.1%). The predominance of adult and elderly subjects, with an old or very old infection, inevitably entails a significant number of HCV RNA+ subjects in the advanced stages of the illness. According to our estimates, approximately 400,000 subjects have cirrhosis, decompensated cirrhosis, and hepatocarcinoma, with a median age of 70 years.The model aims to support policymakers to define action plans by providing an estimate of both the emerged infected population and nonemerged infected population by age, gender, gravity, genotype, and geographical area. In the future, the model may contribute to simulation of the costs and outcome of different action strategies that can be adopted by health authorities.

Bipolar disorder and antithyroid antibodies: review and case series

Mood disorders and circulating thyroid antibodies are very prevalent in the population and their concomitant occurrence may be due to chance. However, thyroid antibodies have been repeatedly hypothesized to play a role in specific forms of mood disorders. Potentially related forms include treatment-refractory cases, severe or atypical depression, and depression at specific phases of a woman’s life (early gestation, postpartum depression, perimenopausal). With regard to bipolar disorder, studies of specific subgroups (rapid cycling, mixed, or depressive bipolar) have reported associations with thyroid antibodies. Offspring of bipolar subjects were found more vulnerable to develop thyroid antibodies independently from the vulnerability to develop psychiatric disorders. A twin study suggested thyroid antibodies among possible endophenotypes for bipolar disorder. Severe encephalopathies have been reported in association with Hashimoto’s thyroiditis. Cases with pure psychiatric presentation are being reported, the antithyroid antibodies being probably markers of some other autoimmune disorders affecting the brain. Vasculitis resulting in abnormalities in cortical perfusion is one of the possible mechanisms.

Thyroid disorders and gastrointestinal and liver dysfunction: A state of the art review

Thyroid disorders commonly impact on the gastrointestinal system and may even present with gastrointestinal symptoms in isolation; for example, metastatic medullary thyroid carcinoma typically presents with diarrhoea. Delays in identifying and treating the underlying thyroid dysfunction may lead to unnecessary investigations and treatment, with ongoing morbidity, and can potentially be life-threatening. Similarly, gastrointestinal diseases can impact on thyroid function tests, and an awareness of the concept and management of non-thyroidal illness is necessary to avoid giving unnecessary thyroid therapies that could potentially exacerbate the underlying gastrointestinal disease. Dual thyroid and gastrointestinal pathologies are also common, with presentations occurring concurrently or sequentially, the latter after a variable time lag that can even extend over decades. Such an association aetiologically relates to the autoimmune background of many thyroid disorders (e.g. Graves' disease and Hashimoto's thyroiditis) and gastrointestinal disorders (e.g. coeliac disease and inflammatory bowel disease); such autoimmune conditions can sometimes occur in the context of autoimmune polyglandular syndrome. Emphasis should also be given to the gastrointestinal side effects of some of the medications used for thyroid disease (e.g. anti-thyroid drugs causing hepatotoxicity) and vice versa (e.g. interferon therapy causing autoimmune thyroid dysfunction). In this review, we discuss disorders of the thyroid-gut axis and identify the evidence base behind the management of such disorders.

Both thyroid autoimmunity and increased serum TSH are independent risk factors for malignancy in patients with thyroid nodules

AIM

To assess the relevance of thyroid autoimmunity and TSH as risk factors for malignancy in thyroid nodules (TN).

SUBJECTS AND METHODS

Retrospective analysis on 2053 patients with single/prevalent TN submitted to fine needle aspiration cytology (FNAC). Anti-thyroid autoantibodies (ATA) [anti-thyroperoxidase (TPOAb), anti-thyroglobulin (TgAb)] and TSH were measured. Cytology was classified as benign (class II), indeterminate (class III), and suspicious or malignant (class IV). Histology was available in 301 patients. Associations of malignancy with independent variables were determined by multivariate logistic regression analysis.

RESULTS

Higher prevalence of class IV (14.2% vs 6.8%: p<0.001) and class III (23.5% vs 17.1%: p<0.001) were found in ATA+ vs ATA- TN. Histology confirmed increased prevalence of cancer in ATA+ (p<0.05) TN and in those with diffuse lymphocytic thyroid infiltration (p<0.05). Interestingly, the prevalence of malignancies observed in operated class III nodules was strikingly lower in ATA+ (1/20, 5%), than in ATA- patients (34/67, 50.7%; p<0.001). Increased independent odds ratio (OR) for malignancy was conferred by any ATA [OR 2.21; 95% confidence interval (CI)=1.49-3.29, p<0.0001]; TPOAb (OR 2.15; CI=1.42-3.25, p<0.0001) and TgAb (OR 1.67; CI=1.05-2.67, p<0.05), by serum TSH>1.0 μUI/ml (OR 1.95; CI=1.01-3.76, p<0.05), and by young age (10-29 yr: OR 2.09; CI=1.02-4.26, p<0.05). A formula was calculated to assess the relative contribution of ATA, TSH, and age to the risk of TN malignancy.

CONCLUSIONS

Both thyroid autoimmunity and increased TSH represent independent risk factors for TN malignancy.

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.

Thyroid disturbance related to chronic hepatitis C infection: role of CXCL10

Association between autoimmune thyroid diseases (AITD) and hepatitis C is controversial, but may occur or worsen during alpha-interferon treatment. The mechanism responsible for autoimmune diseases in infected patients has not been fully elucidated. This study aims to evaluate the frequency of AITD in chronic hepatitis C and the association of chemokine (CXC motif) ligand 10 (CXCL10) and AITD. One hundred and three patients with chronic hepatitis C and 96 controls were prospectively selected to clinical, hormonal, thyroid autoimmunity and ultrasound exams, besides thyroxine-binding globulin (TBG) and CXCL10 measurements and hepatic biopsies. The frequency of AITD among infected subjects was similar to controls. TT3 and TT4 distributions were right shifted, as was TBG, which correlated to both of them. Thyroid heterogeneity and hypoechogenicity were associated with AITD. Increased vascularization was more prevalent in chronic hepatitis C.CXCL10 was higher in infected patients (p=0.007) but was not related to thyroid dysfunction. Increase in CXCL10 levels were consistent with hepatic necroinflammatory activity (p=0.011). In summary, no association was found between chronic hepatitis C and AITD. Infected subjects had higher TT3 and TT4 which were correlated to TBG. Increased CXCL10 was not associated to thyroid dysfunction in HCV-infected population.

Autoimmune manifestations in viral hepatitis

Infections by the viruses responsible for hepatitis B, C and D are accompanied by a number of immunopathological manifestations. A link between infection and autoimmunity is particularly well documented for the hepatitis C virus. Immunopathological manifestations range from production of autoantibodies to overt autoimmune disease, including thyroiditis and autoimmune hepatitis, and to immune-complex-mediated disorders, including cryoglobulinaemia, glomerulonephritis and vasculitis. Several of these manifestations improve with successful antiviral treatment, directly incriminating the virus in their pathogenesis. Mechanisms considered responsible for hepatitis virus-related immunopathology, including molecular mimicry, impairment of regulatory T cells and activation of B lymphocytes, will be examined in this review.

Prevalence of thyroid autoantibodies in hepatitis C and hepatitis B infection in China

OBJECTIVE

To explore the correlation between anti-thyroid autoantibodies and hepatitis C virus (HCV) infection.

METHODS

We collected 462 samples with positive thyroid peroxidase antibody (TPOAb) and/or thyroglobulin antibody (TgAb). Matched for age and gender, 380 subjects with negative TPOAb and TgAb were selected as controls. A third-generation enzyme linked immunosorbent assay (ELISA) was used to examine the presence of anti-HCV antibody. We also examined RNA HCV expression of subjects with positive anti-HCV antibody. Separate groups of 195 subjects with hepatitis C, 150 healthy subjects, and 150 subjects with hepatitis B were tested for thyroid-related markers.

RESULTS

The HCV infection rate was 1.30% in 462 subjects with positive thyroid autoantibodies, and 0.53% in 380 subjects who were negative for thyroid autoantibodies. There was no significant difference in the HCV infection rate between the two groups (χ(2)=1.322, p>0.05). In subjects with hepatitis C, 30.77% were TPOAb positive and 30.77% were TgAb positive; subjects with hepatitis C appeared to show significantly higher positivity of antithyroid autoantibodies when compared with healthy subjects and those with hepatitis B (χ(2)=21.496, χ(2)=30.454, p<0.01).

CONCLUSION

The HCV infection rate did not seem to be higher in subjects with abnormal thyroid autoimmunity. However, the positivity of thyroid autoantibodies appeared to be increased in subjects with hepatitis C, suggesting that thyroid-related markers should be examined in hepatitis C patients.

Cases of interferon-alpha and interferon-beta-induced thyroiditis

Interferons are currently the major treatment modality for several malignant and non-malignant diseases such as chronic hepatitis C and B, multiple sclerosis, hematological malignancies, malignant melanoma, renal cell carcinoma, etc. Thyroid disorders develop in some of the interferon-treated patients with the incidence ranging from 1% to 35%. These complications may often result in dose reduction or discontinuation of interferon therapy. Interferon induced thyroid disorders can be classified as autoimmune and non-autoimmune thyroiditis. There are many studies on the development of thyroid dysfunction in interferon-alpha treated patients with chronic hepatitis C and in patients with multiple sclerosis treated with interferon-beta. There is a dearth of information about the incidence and characteristics of thyroid abnormalities in patients with hematological malignancies receiving interferon-alpha. A number of genetic determinants are discussed as causes for thyroid impairment (sex, age, ethnic group, genes involved in the thyroid immune regulation), as well as non-genetic factors (related to the underlying disease--hepatitis C virus; multiple sclerosis; therapeutic regimens of interferon administration, iodine concentration in the environment, presence of thyroid autoantibodies at the start of treatment, etc.). In this article we summarize the relevant data about the frequency and characteristics of thyroid disorders in patients treated with interferons, the risk factors and the mechanisms for their development and the peculiarities of the course, detection and treatment of these complications. The review of the literature motivates studying the thyroid function of specific groups of patients receiving interferon in order to clarify the influence of the factors drug and disease on the thyroid gland. Early detection and adequate treatment of thyroid dysfunction in these patients is important to avoid complications that may compromise treatment.

Hepatitis C and interferon induced thyroiditis

Autoimmune thyroid diseases (AITDs) are complex diseases that develop as a result of interactions between genetic, epigenetic, and environmental factors. Significant progress has been made in our understanding of the genetic and environmental triggers contributing to AITD. The major environmental triggers of AITD include iodine, smoking, medications, pregnancy, and possibly stress. In this review we will focus on two well-documented environmental triggers of AITD, hepatitis C virus (HCV) infection and interferon alpha (IFNa) therapy. Chronic HCV infection has been shown to be associated with increased incidence of clinical and subclinical autoimmune thyroiditis (i.e. the presence of thyroid antibodies in euthyroid subjects). Moreover, IFNa therapy of chronic HCV infection is associated with subclinical or clinical thyroiditis in up to 40% of cases which can be autoimmune, or non-autoimmune thyroiditis. In some cases interferon induced thyroiditis (IIT) in chronic HCV patients may result in severe symptomatology necessitating discontinuation of therapy. While the epidemiology and clinical presentation of HCV and interferon induced thyroiditis have been well characterized, the mechanisms causing these conditions are still poorly understood.

Estimating the incidence, prevalence and clinical burden of hepatitis C over time in Italy

Our objective was to estimate HCV clinical burden over time in Italy. A national age-specific HCV prevalence in 1995 was obtained from studies conducted in general population samples and intravenous drug users. Age profile of new HCV infections and trend of incidence since 1985 were derived from a database of reported acute HCV infections. These incidence and prevalence data were used to estimate HCV burden from 1950 to 2030 by mathematical modelling. Different rates of HCV related liver disease progression were tested to assess the robustness of estimates. It is estimated that HCV had a major spread in Italy in 1945-1969. HCV RNA-positive subjects peaked around 1970; their prevalence in 2005 was 3.2%, 58% of them being >65 y of age. The number of individuals with HCV related cirrhosis and that of HCV liver related deaths peaked in 1980-1985. In 2005, they were approximately 230,000 (range 150,000-240,000, according to lower or higher disease progression rates) and approximately 7,000 (range 2200-12,300), respectively: both will be halved by 2025. In conclusion, unlike other industrialized countries, the burden of clinically relevant HCV-positive cases in Italy is already on the decline and will further reduce in the future. This is due to differences in the age-specific prevalence, most of HCV-positive Italians currently being >65 y of age.

Interferon induced thyroiditis

Interferon-alpha (IFNalpha) is used for the treatment of various disorders, most notable chronic hepatitis C virus (HCV) infection. One of the commonest side effects of IFNalpha therapy is thyroiditis, with up to 40% of HCV patients on IFNalpha developing clinical or subclinical disease. In some cases interferon induced thyroiditis (IIT) may result in severe symptomatology necessitating discontinuation of therapy. IIT can manifest as clinical autoimmune thyroiditis, presenting with symptoms of classical Hashimoto's thyroiditis or Graves' disease, or as non-autoimmune thyroiditis. Non-autoimmune thyroiditis can manifest as destructive thyroiditis, with early thyrotoxicosis and later hypothyroidism, or as non-autoimmune hypothyroidism. While the epidemiology and clinical presentation of IIT have been well characterized the mechanisms causing IIT are still poorly understood. It is likely that the hepatitis C virus (HCV) itself plays a role in the disease, as the association between HCV infection and thyroiditis is well established. It is believed that IFNalpha induces thyroiditis by both immune stimulatory effects and by direct effects on the thyroid. Early detection and therapy of this condition are important in order to avoid complications of thyroid disease such as cardiac arrhythmias.

Thyroid dysfunction in patients with chronic hepatitis C: virus- or therapy-related?

BACKGROUND AND AIMS

Thyroid dysfunction (TD) represents an extrahepatic manifestation of chronic hepatitis C (CHC). Moreover, the currently approved treatment of CHC is often associated with TD. However, it remains debatable if TD is mainly virus- or treatment-related. The aim of this study was to assess the incidence and features of TD, and to identify its predictors in treated and untreated CHC patients.

METHODS

Ninety-four patients with CHC and normal thyroid function were evaluated long-term for TD: 33 were untreated (control group) and 61 were treated with pegylated interferon alpha (PEG-IFN-alpha) plus ribavirin (treatment group). Mean follow up was 80.1 and 39.4 months, respectively.

RESULTS

All patients in the control group remained euthyroid, while 13 treated patients (21.3%) developed TD (P < 0.001). Eleven of these were diagnosed with hypothyroidism and two with hyperthyroidism, which then converted to hypothyroidism. In the majority of cases (9/13, 69.2%) TD did not reverse after treatment discontinuation and required hormone replacement therapy. Pretreatment virological parameters did not predict TD, according to multiple logistic regression analysis. TD was not associated with total dose of PEG-IFN-alpha or ribavirin, viral kinetics or with virological outcome, but it was linked to development of other therapy-related autoimmune disorders (odds ratio, 8.29).

CONCLUSION

Antiviral therapy of CHC possibly induces de novo or exacerbates pre-existing silent TD. TD does not seem to correlate with any pretreatment virological parameter; it is probably not related to dose or treatment duration, nor linked to viral kinetics or virological outcome. The role of chronic hepatitis C per se in TD remains to be determined.

Interferon alpha treatment and thyroid dysfunction

Interferon alpha (IFN alpha) is the cornerstone therapeutic agent for chronic hepatitis C virus (HCV) infection. Prospective studies have shown that up to 15% of HCV patients receiving IFN alpha develop clinical thyroid disease, and up to 40% become thyroid antibody positive. In some cases IFN-induced thyroiditis (IIT) may result in discontinuation of interferon therapy; thus, IIT represents a major clinical problem for hepatitis C patients receiving IFN alpha therapy. Recently, the mechanisms leading to the development of IIT have begun to be unraveled. It is now clear that HCV itself plays a role in the disease. Moreover, recent data suggest the IFN alpha precipitates thyroiditis by both immune modulatory mechanisms and direct thyroid toxic effects. Genetic factors also play a major role in the etiology of IIT. IIT can manifest both as clinical autoimmune thyroiditis (ie, Hashimoto's thyroiditis and Graves' disease) and as nonautoimmune thyroiditis (ie, destructive thyroiditis). Early detection and therapy of these conditions are important to avoid complications of thyroid disease such as cardiac arrhythmias. This article reviews the epidemiology and clinical manifestations of IIT and the mechanisms causing IIT, focusing on the role of HCV.

Widespread and ample peptide overlapping between HCV and Homo sapiens proteomes

Alignment of protein sequences is fundamental in analyzing homology, evolutionary events and functional relationships. Searching for the epitopic peptide platform underlying hepatitis C virus (HCV) infection and autoimmune phenomena, we have used sequence-sequence peptide matching to compare the HCV polyprotein sequence to the human proteome. The following results were obtained: (1) pentamers from HCV polyprotein have a widespread and high level of similarity to a large number of human proteins (19,605 human proteins, that is 57.6% of the human proteome); (2) remarkable similarity between the two proteomes persists even using longer peptide motifs as probes for identity scanning; (3) only a limited number of HCV pentameric fragments have no similarity to the human host, so representing molecular sequence signatures of the virus. We conclude that the widespread sharing of numerous perfect exact matches between HCV and human proteomes might explain HCV persistence in humans.

Fifteen-year follow-up of thyroid function in lithium patients

OBJECTIVE

To study prospectively the course of clinically relevant thyroid dysfunction in a cohort of patients on long-term lithium treatment.

METHOD

Patients (no.=150) who had undergone a cross-sectional evaluation of their thyroid function in 1989, when they were at different stages of lithium treatment, were followed up for thyroid circulating thyroid antibodies, hypothyroidism, hyperthyroidism, and thyroidectomy, during a further period of lithium exposure of up to 15 yr.

RESULTS

Annual rates of newly developed circulating thyroid antibodies and hypothyroidism were 1.7 and 1.5%, respectively. Subjects with thyroid antibodies had a higher chance of requiring substitution treatment with levothyroxine for hypothyroidism compared with subjects with no evidence of thyroid antibodies (6.4% annual rate compared to 0.8%; relative risk: 8.4; 95% confidence interval: 2.9-24.0). One case of hyperthyroidism was observed over 976 patient-yr. Three patients underwent thyroidectomy during followup (two for multinodular goiter and one for multicentric papillary carcinoma).

CONCLUSIONS

Lithium may be associated with hypothyroidism in particular in the presence of circulating thyroid antibodies. Incidence of thyroid antibodies is comparable with that reported for the general population. Hyperthyroidism and thyroid cancer are rare.

Thyroid cancer in HCV-related chronic hepatitis patients: a case-control study

OBJECTIVE

The present study prospectively investigated prevalence and features of thyroid cancer in patients with hepatitis C virus-related chronic hepatitis (HCV+) in comparison to two samples from the general population with different iodine intake.

DESIGN

We studied the prevalence of thyroid cancer in 308 unselected HCV+ patients in comparison to two population-based, gender- and age-matched control groups: 1) 616 subjects from an iodine deficient area; 2) 616 subjects from an iodine-sufficient area. Thyroid status was assessed by measurement of circulating thyroid hormones and autoantibodies, thyroid ultrasonography, and when indicated, fine-needle aspiration cytology.

MAIN OUTCOME

Circulating thyrotropin, anti-thyroglobulin, and anti-thyroperoxidase antibodies levels, and the prevalence of hypothyroidism were significantly higher in HCV+ patients (p < 0.001 for all). Six patients with papillary thyroid cancer were detected among HCV+ patients, whereas no case was observed in control 1 (p = 0.001), and only one case was observed in control 2 (p = 0.003). In HCV+ patients 83% with thyroid cancer had evidence of thyroid autoimmunity vs 31% of the other HCV+ patients (p = 0.02).

CONCLUSIONS

These data suggest a high prevalence of thyroid papillary cancer in HCV+ patients, overall in presence of thyroid autoimmunity; careful thyroid monitoring is indicated during the follow-up of these patients.

Extrahepatic manifestations of Hepatitis C Virus infection: a general overview and guidelines for a clinical approach

Hepatitis C Virus is associated with a wide series of extrahepatic manifestations. Based on available data the link between the virus and some of these extrahepatic diseases is only suggested and needs further confirmation. Hepatitis C Virus-related lymphoproliferative disorders, whose prototype is mixed cryoglobulinaemia, represent the most closely related extrahepatic manifestations of Hepatitis C Virus. Other Hepatitis C Virus-associated disorders include nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, porphyria cutanea tarda, lichen planus, diabetes, chronic polyarthritis, cardiopathy and atherosclerosis. A pathogenetic link between Hepatitis C Virus and some extrahepatic manifestations was confirmed by their responsiveness to antiviral therapy, which is now deemed the first therapeutic option to consider. By contrast, there are diseases where treatment with interferon was ineffective or dangerous. The aim of the present paper is to outline the most recent evidence concerning extrahepatic disorders that are possibly associated with Hepatitis C Virus infection. Special emphasis will be given to discussion of the most appropriate clinical approaches to be adopted in order to diagnose, treat (possibly prevent) and follow-up extrahepathic diseases in patients with Hepatitis C Virus infection.

Thyroid disorders in chronic hepatitis C virus infection

The prevalence of thyroid disorders has been evaluated in patients with hepatitis C virus (HCV) infection by many studies. From a review of the published controlled studies, it is possible to observe that: (1) most investigated patients with chronic HCV hepatitis, while a minority evaluated hepatitis C virus antibody (HCVAb)- seropositive patients (the two conditions are not comparable with regards to thyroidal repercussions, in fact, HCVAb-seropositive patients do not necessarily display changes of the immune system present in chronically infected HCV patients); and (2) some authors selected as internal control hepatitis B virus (HBV)-infected patients, while others selected apparently healthy controls or HCVAb-negative subjects. Pooling all data about HCV-positive patients (with chronic hepatitis or HCVAb positivity) and using as control the sum of healthy controls, HBV-infected patients and sera negative for HCVAb, a significant increase of the prevalence has been observed both for thyroid autoimmune disorders (odds ratio [OR] = 1.6; 95% confidence interval = [C]) 1.4-1.9) as well as for hypothyroidism (OR = 2.9; 95% CI = 2.0-4.1). The results of the epidemiologic studies showing an association between HCV infection and thyroid cancer need to be confirmed. The abovementioned evidences seem sufficient to suggest careful thyroid monitoring during the follow-up of patients with HCV infection.

The clinical and physiological spectrum of interferon-alpha induced thyroiditis: toward a new classification

Interferon-alpha (IFNalpha) is a major treatment modality for several malignant and nonmalignant diseases, especially hepatitis C. Prospective studies have shown that up to 15% of patients with hepatitis C receiving IFNalpha develop clinical thyroid disease, and up to 40% were reported to develop thyroid antibodies. Some of these complications may result in discontinuation of interferon therapy. Thus, interferon induced thyroiditis (IIT) is a major clinical problem for patients receiving interferon therapy. IIT can be classified as autoimmune type and non-autoimmune type. Autoimmune IIT may manifest by the development of thyroid antibodies without clinical disease, or by clinical disease which includes both autoimmune hypothyroidism (Hashimoto's thyroiditis) and autoimmune thyrotoxicosis (Graves' disease). Non-autoimmune IIT can manifest as destructive thyroiditis or as hypothyroidism with negative thyroid antibodies. Early detection and therapy of these conditions is important in order to avoid complications of thyroid disease such as cardiac arrhythmias. While it is not clear which factors contribute to the susceptibility to IIT, recent evidence suggests that genetic factors, gender, and hepatitis C virus infection may play a role. In contrast, viral genotype and therapeutic regimen do not influence susceptibility to IIT. The etiology of IIT is unknown and may be secondary to immune modulation by IFNalpha and/or direct effects of interferon on the thyroid. In this review we discuss the clinical and pathophysiological aspects of IIT, and we are proposing a new, etiology-based classification of IIT, as well as an algorithm for diagnosis and treatment of IIT.

A case control study on psychiatric disorders in Hashimoto disease and Euthyroid Goitre: not only depressive but also anxiety disorders are associated with thyroid autoimmunity

Objective

To evaluate the association between mood and anxiety disorders in Hashimoto disease and Euthyroid Goitre in a case control study.

Methods

Cases included 19 subjects with Hashimoto disease in euthyroid phase, 19 subjects with euthyroid goitre, 2 control groups each of 76 subjects matched (4/1) according to age and sex drawn from the data base of a community based sample. Psychiatric diagnoses were formulated using the International Composite Diagnostic Interview Simplified, according to DSM-IV criteria. All subjects underwent a complete thyroid evaluation including physical examination, thyroid echography and measure of serum free T4 (FT4), free T3 (FT3), thyroid-stimulating hormone (TSH) and anti-thyroid peroxidase autoantibodies (anti-TPO). Results: Subjects with Hashimoto disease showed higher frequencies of lifetime Depressive Episode (OR = 6.6, C.L. 95% 1.2–25.7), Generalized Anxiety Disorders (OR = 4,9 Cl 95% 1.5–25.4) and Social Phobia (OR = 20.0, CL 95% 2.3–153.3) whilst no differences were found between subjects with goitre and controls.

Conclusion

The study seems to confirm that risk for depressive disorders in subjects with thyroiditis is independent of the thyroid function detected by routine tests and indicates that not only mood but also anxiety disorders may be associated with Hashimoto disease.

Is there anything to the reported association between Helicobacter pylori infection and autoimmune thyroiditis?

Higher serological prevalence rates of Helicobacter pylori (Hp) infection have been reported in patients with autoimmune thyroiditis (AT), and it has been suggested that monoclonal antibodies against Cag-A positive Hp strains can cross-react with follicular cells of the thyroid gland. We studied the prevalence of AT and thyroid functional status in patients who underwent gastroscopy for dyspeptic symptoms. Patients were tested for TSH, free thyroid hormones, and antithyroglobulin and antithyroperoxidase antibodies (ATPO). Hp positivity was determined using urea breath test (UBT). Serum samples from 302 patients (59.9% women) were evaluated. One hundred ninety-one subjects (63.2%) were Hp-negative, and 111 of 302 (36.8%) were Hp-positive. Forty-three of 191 Hp-negative patients (22.5%; 95% CI, 17.1-29.0%) had an increase of either antibody, compared to 30 of 111 (27.0%; 95% CI, 19.6-36.0%) Hp-positive patients (P = 0.40). Similar results were obtained using positivity for both antibodies (7.3 vs. 7.2%; P = 1) or for ATPO (18.8 vs. 21.6%; P = 0.54). The prevalences of hypothyroidism (4.7 vs. 5.5%) or hyperthyroidism (5.8 vs. 5.5%) were also similar (P = 0.95). Hormonal levels were not different in the two groups (P > 0.22 in all cases). The previously reported association between AT and Hp infection was not observed in our study. Infection by Hp does not appear to increase the risk of AT in individuals with dyspeptic symptoms, and screening for this condition in patients with a positive UBT is not indicated.

Interferon induced Autoimmune Thyroid Disease (AITD): a model for human autoimmunity

Interferon (IFN) alpha treatment for various conditions has been associated with thyroid autoimmunity. The incidence of interferon induced thyroid autoimmunity has been reported to range from 2.5% to 42%, possibly depending upon dose and duration of medical therapy and patient characteristics. It is not known whether IFN-alpha initiates autoimmune thyroid disease (AITD) or simply exacerbates AITD in individuals with subclinical AITD.

The link between thyroid autoimmunity (antithyroid peroxidase autoantibodies) with anxiety and mood disorders in the community: a field of interest for public health in the future

BACKGROUND

To evaluate the association between mood and anxiety disorders and thyroid autoimmunity in a community sample.

METHODS

A community based sample of 222 subjects was examined. Psychiatric diagnoses were formulated using the International Composite Diagnostic Interview Simplified (CIDIS), according to DSM-IV criteria. All subjects underwent a complete thyroid evaluation including physical examination, thyroid echography and measure of serum free T4 (FT4), free T3 (FT3), thyroid-stimulating hormone (TSH) and anti-thyroid peroxidase autoantibodies (anti-TPO).

RESULTS

16.6% of the overall sample had an anti-TPO value above the normal cut-off. Subjects with at least one diagnosis of anxiety disorders (OR = 4.2, C.L. 95% 1.9-38.8) or mood disorders (OR = 2.9, Cl 95% 1.4-6.6, P < 0.011) were positive for serum anti-TPO more frequently than subjects without mood or anxiety disorders. A statistically significant association with anti-TPO+ was found in Anxiety Disorder Not Otherwise Specified (OR = 4.0, CL 95% 1.1-15.5), in Major Depressive Episode (OR = 2.7, CL 95% 1.1-6.7) and Depressive Disorder Not Otherwise Specified (OR = 4.4, S CL 95% 1-19.3).

CONCLUSIONS

The study seems to suggest that individuals in the community with thyroid autoimmunity may be at high risk for mood and anxiety disorders. The psychiatric disorders and the autoimmune reaction seem to be rooted in a same (and not easy correctable) aberrancy in the immuno-endocrine system. Should our results be confirmed, the findings may be of great interest for future preventive and case finding projects.

Thyroid involvement in patients with overt HCV-related mixed cryoglobulinaemia

BACKGROUND

Mixed cryoglobulinaemia (MC), a systemic vasculitis associated with hepatitis C virus (HCV) infection in >90% of cases, is frequently complicated by multiple organ involvement. The prevalence of thyroid disorders in MC has not yet been studied.

AIM

To investigate the prevalence and clinical features of thyroid involvement in patients with HCV-associated MC (HCV + MC).

DESIGN

Case-control study.

METHODS

HCV + MC patients (n = 93, 17 men and 76 women, mean +/- SD age 63 +/- 10 years, mean disease duration 14 +/- 7 years) consecutively referred to the Rheumatology Unit were matched by sex and age (+/- 2 years) to (i) 93 patients with chronic C hepatitis (CH) without MC and (ii) 93 healthy (HCV-negative) controls from the local population. Measurements included prevalence of hypo- or hyperthyroidism, thyroid autoantibodies, thyroid nodules and thyroid cancer.

RESULTS

By McNemar's chi(2) test, the following thyroid abnormalities were significantly more frequent in HCV + MC patients than in HCV-negative controls: serum anti-thyroperoxidase autoantibody (AbTPO) (28% vs. 9%, p = 0.001); serum AbTPO and/or anti-thyroglobulin autoantibody (31% vs. 12%, p = 0.004); subclinical hypothyroidism (11% vs. 2%, p = 0.038); thyroid autoimmunity (35% vs. 16%, p = 0.006). Serum AbTPO were also significantly more frequent in HCV + MC patients than in CH controls (28% vs. 14%, p = 0.035).

DISCUSSION

The prevalence of thyroid disorders is increased in patients with HCV-related mixed cryoglobulinaemia. We suggest careful monitoring of thyroid function in these patients.

Frontal cortical perfusion abnormalities related to gluten intake and associated autoimmune disease in adult coeliac disease: 99mTc-ECD brain SPECT study

OBJECTIVE

Since brain perfusion abnormalities have been described by single-photon emission computed tomography in some autoimmune diseases, the aim of the present study was to evaluate the incidence of perfusion abnormalities by brain single-photon emission computed tomography in a group of coeliac disease patients, and to investigate whether gluten intake and associated autoimmune diseases may be considered risk factors in causing cerebral impairment.

METHODS

Thirty-four adult coeliac patients (16 on a gluten-free diet and 18 on a gluten-containing diet, 18 (53%) with autoimmune diseases) underwent 99mTc-ethyl cysteinate dimer brain single-photon emission computed tomography and qualitative evaluation of brain perfusion was performed together with a semiquantitative estimation using the asymmetry index. Ten subjects on our database, matched for sex, age and ethnic group, who were proved normal by histology ofjejunal mucosa (four males and six females; median age 39 years, range 27-55 years), were included as control group.

RESULTS

Twenty-four out of 34 patients (71%) showed brain single-photon emission computed tomography abnormalities confirmed by abnormal regional asymmetry index (>5%; range 5.8-18.5%). Topographic comparison of the brain areas showed that the more significant abnormalities were localised in frontal regions, and were significantly different from controls only in coeliac disease patients on unrestricted diet. The prevalence of single-photon emission computed tomography abnormalities was similar in coeliac disease patients with (74%) and without (69%) associated autoimmune disease.

CONCLUSIONS

Abnormalities of brain perfusion seem common in coeliac disease. This phenomenon is similar to that previously described in other autoimmune diseases, but does not appear to be related to associated autoimmunity and, at least in the frontal region, may be improved by a gluten-free diet.

Thyroid disorders in chronic hepatitis C

PURPOSE

To explore the association of hepatitis C virus (HCV) infection with thyroid disorders.

METHODS

We investigated the prevalence of thyroid disorders in 630 consecutive patients with chronic hepatitis due to HCV infection; all patients were free of cirrhosis and hepatocarcinoma, and were not on interferon treatment. Also included were a control group of 389 subjects from an iodine-deficient area, another control group of 268 persons living in an area of iodine sufficiency, and 86 patients >40 years of age with chronic hepatitis B. Levels of thyroid-stimulating hormone (TSH), free thyroxine (T(4)), and triiodothyronine (T(3)), as well as anti-thyroglobulin and anti-thyroid peroxidase antibodies, were measured.

RESULTS

Mean TSH levels were higher (P = 0.001), and free T(3) and free T(4) levels were lower (P <0.0001), in patients with chronic hepatitis C than in all other groups. Patients with chronic hepatitis C were more likely to have hypothyroidism (13% [n = 82]), anti-thyroglobulin antibodies (17% [n = 108]), and anti-thyroid peroxidase antibodies (21% [n = 132]) than were any of the other groups.

CONCLUSION

Both hypothyroidism and thyroid autoimmunity are more common in patients with chronic hepatitis C-even in the absence of cirrhosis, hepatocellular carcinoma, or interferon treatment-than in normal controls or those with chronic hepatitis B infection.

Expression of endocrine autoantibodies in chronic hepatitis C, before and after interferon-alpha therapy

Interferon-alpha (IFN-alpha) treatment for chronic hepatitis C (CHC) has been associated with thyroid autoimmunity and/or dysfunction. Only a few data concerning the prevalence of islet-cell or adrenal cortex autoantibodies in IFN-alpha-treated subjects are currently available. The aims of our study were to evaluate in CHC, 1) the prevalence and association of thyroid, islet-cell and adrenal autoantibodies, and 2) the appearance of endocrine dysfunction, before and after a 6 month IFN-alpha treatment. We analyzed serum samples from 203 adult patients at the time of clinical diagnosis of CHC and showed that the prevalence of thyroperoxidase (TPOAb), thyroglobulin (TGAb), TSH-receptor (TRAb), glutamic acid decarboxylase (GAD65Ab), IA-2/ICA512 (IA-2/ICA512Ab) and 21-hydroxylase (21OHAb) autoantibodies was similar to that observed among healthy control subjects of similar age and sex distribution. Among 99 patients with follow-up serum samples, 83 accepted and 16 refused IFN-alpha treatment. The IFN-alpha treatment was associated with increase of TPOAb levels in 3 subjects already positive at baseline, with progression to overt hypothyroidism in 2 of them. The de novo appearance of autoantibodies was observed in 5/80 (6%) cases for TPOAb, 1/81 (1.2%) for GAD65Ab and 2/81 (2.5%) for IA-2/ICA512Ab. Clinical or subclinical signs of either hyperthyroidism or hypothyroidism were demonstrated in 3/5 cases with de novo appearance of TPOAb. Four subjects, initially positive for either GAD65Ab or IA2/ICA512Ab, were all found negative after IFN-alpha-treatment. No subjects showed positivity for 21OHAb either at baseline or after the follow-up period. Our study suggests that, in CHC untreated patients, the prevalence of endocrine autoantibodies is similar to that observed in the general population. Furthermore, we demonstrate that IFN-alpha treatment is associated with the induction or enhancement of thyroid, but not of islet-cell or adrenal cortex autoimmunity.

Disease associations with autoimmune thyroid disease

Autoimmune thyroid disease (AITD) is common and occurs frequently in conjunction with other diseases. Many putative disease associations have been suggested for AITD but the validity of these associations is not clear in all cases. It is important to define disease associations correctly because this may offer a means to rationally screen for true associations, may shed light on shared pathophysiologic mechanisms and may be important if the associated disease impacts on patient management. This review has examined the evidence base for a large number of the suggested associations.

Association between panic disorder, major depressive disorder and celiac disease: a possible role of thyroid autoimmunity

OBJECTIVE

To evaluate the association between celiac disease and specific anxiety and depressive disorders and to identify potential common pathogenetic links, with particular regard to thyroid function and autoimmunity.

METHODS

Cases included 36 adult celiac patients, 25 females and 11 males, aged 18-64 years. Controls comprised 144 healthy subjects matched by sex and age with no clinical evidence or family history of celiac disease. Diagnosis of celiac disease was made on the basis of clinical history and serological criteria. Psychiatric diagnoses were formulated using the International Composite Diagnostic Interview, according to DSM-IV criteria. Thyroid was evaluated by palpation, echography and measurement of serum-free thyroid hormones (FT4, FT3), thyroid-stimulating hormone (TSH) and antithyroid autoantibodies (anti-TPO).

RESULTS

Compared to controls, a significantly higher number of celiac patients met criteria for lifetime [15 (41.7%) versus 30 (29.8%), P < .01] and 6-month [7 (19.4%) versus 9 (6.2%), OR = 3.2, chi(2) = 5.2, P < .05] major depressive disorder (MDD) and lifetime [5 (13.9%) versus 3 (2.1%), P < .001] and 6-month [3 (8.1%) versus 2 (1.4%), P < .05] panic disorder (PD). Anti-TPO prevalence was significantly higher in celiac patients than in the control group (11/36 = 30.5% versus 14/144 = 9.7%, P < .001). A higher frequency of PD and MDD was found in celiac patients with positive anti-TPO when compared to negative anti-TPO patients (4/11 = 36.4% PD in TPO+ versus 1/25 = 4% PD in TPO-, P < .01; 9/11 = 81.8% MD in TPO+ versus 6/25 = 9.5% MD in TPO-, P < .01).

CONCLUSION

Patients affected by celiac disease tend to show a high prevalence of PD and MDD and association with subclinical thyroid disease appears to represent a significant risk factor for these psychiatric disorders.

Thyroid ultrasonography as a tool for detecting thyroid autoimmune diseases and predicting thyroid dsfunction in apparently healthy subjects

In order to establish its usefulness for the diagnosis and follow-up of thyroid autoimmune diseases, thyroid ultrasonography together with free T4 (FT4), free T3 (FT3), TSH, antibodies (Tg Ab) and thyroperoxidase antibodies (TPO Ab) were performed and re-evaluated during a 3-yr follow-up in 482 apparently healthy subjects, living in a borderline iodine-sufficient urban area. Thyroid dysfunction was found in 7 out of 12 (58.3%) subjects with circulating thyroid autoantibodies, who also had thyroid hypoechogenicity (2 had overt and 3 subclinical hypothyroidism at booking; 2 developed subclinical hypothyroidism during the follow-up), and in none of the 12 subjects with normal thyroid echostructure (chi2=7.26, p=0.007). Thyroid dysfunction was found in 4 out of 29 (13.7%) subjects with negative Tg and/or TPO Ab who also had thyroid hypoechogenicity (1 had Graves' disease at booking, 1 developed Graves' disease and 2 subclinical hypothyroidism during the follow-up), and in none of the 429 with normal thyroid echostructure (chi2=82.03, p<0.0001). Although positive TPO and/or Tg Ab were more frequent (24/482, 5%) in subjects with thyroid dysfunction (7/11) than in those who remained euthyroid during the study (17/471, chi2=69.66, p<0.0001), thyroid hypoechogenicity had a higher sensitivity than the positivity of thyroid autoantibody tests (100 vs 63.3%) for diagnosing or predicting thyroid dysfunction.

IN CONCLUSION

1) thyroid ultrasonography is a useful tool to detect thyroid autoimmune disease in apparently healthy subjects; 2) present and future thyroid dysfunction is more readily predicted by a hypoechogenic pattern at thyroid ultrasound than by the occurrence of serum thyroid autoantibodies.

Prevalence of silent celiac disease in patients with autoimmune thyroiditis from Northern Sardinia

Celiac disease (CD) is frequently associated with other autoimmune diseases such as Type 1 diabetes mellitus, autoimmune thyroiditis (AT), and Addison's disease. The frequency of these associations varies with the populations studied. We conducted this study to ascertain the prevalence of CD in patients with AT from Sardinia, an area with a very high prevalence of CD. To this aim, 297 consecutive patients with AT (as defined by elevated antithyroid antibody levels and a positive ultrasound scan) were studied. Immunoglobulin A and G-class antigliadin antibodies were assayed in serum; if either or both were positive, antiendomysium antibodies were determined. If two markers were positive, serum ferritin, folate, and vitamin B12 levels were measured and jejunal biopsy was suggested. Thirteen out of the 14 patients who showed at least two positive markers consented to jejunal biopsy and all of them showed histological features of CD. The prevalence of CD in AT patients was 4-fold greater than that observed in the general population (4.37 vs 1.06%, p<0.0001). Ferritin was low in 6 and vitamin B12 in 2 out of 13 patients; serum folates were normal in all patients. Molecular typing of HLA class II alleles showed an increased frequency of the extended haplotype DRB1*0301/DQA1*0501/DQB1*0201. None of our patients had a history of gastrointestinal symptoms. We confirm the increased prevalence of silent CD in patients with AT. Patients with AT ought to be regarded as a high-risk group for CD and should be screened routinely for it; if negative, screening tests should be repeated at regular intervals.