Hashimoto's thyroiditis and coexisting disorders in correlation with HLA status-an overview

Antithyroid Antibodies and Reproductive Parameters of Women with Hashimoto's Thyroiditis

OBJECTIVES/INTRODUCTION

To evaluate the presence and concentration of antithyroid peroxidase (TPOAb) and antithyroglobulin (TGAb) antibodies at the onset of Hashimoto's Thyroiditis (HT) and their association with disease characteristics and reproductive parameters before and after diagnosis.

METHODS

This is a cross-sectional study with 65 women with HT followed in an outpatient clinic. The data was collected by interviews and review of medical records. The variables were characteristics of the disease; TPOAb and TGAb measurements; pregnancies; live children; premature births; pregnancy losses and infertility. We used the chi-square or Fisher's exact tests, the Mann-Whitney test and the Spearman correlation. The significance level was set at 5%.

RESULTS

The mean age at diagnosis was 38 (SD ± 11.1) years and the duration of the disease was 7.5 (SD ± 5.3) years; 46% of the women reported infertility periods. 59/65 (90.7%) women had TPOAb and 42 (64.6%) had TGAb antibodies. Comparison between the groups with and without TPOAb or TGAb showed no differences between all variables studied. We found positive correlations between TPOAb concentration and preterm births and thyroid volume; and TGAb concentration was positively correlated with age.

CONCLUSION

The presence of autoantibodies did not influence reproductive parameters; TPOAb concentration was correlated with premature births and thyroid volume.

Alcohol Consumption and Autoimmune Diseases

Alcohol is the second-most misused substance after tobacco. It has been identified as a causal factor in more than 200 diseases and 5.3% of all deaths and is associated with significant behavioral, social, and economic difficulties. As alcohol consumption may modulate the immune system's regulatory mechanisms to avoid attacking the body's tissues, it has been proven to play a dichotomic role in autoimmune diseases (ADs) based on the quantity of consumption. In this review, we report updated evidence on the role of alcohol in ADs, with a focus on alcohol addiction and the human biological immune system and the relationship between them, with alcohol as a risk or protective factor. Then, in this narrative review, we report the main evidence on the most studied ADs where alcohol represents a key modulator, including autoimmune thyroiditis, multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, diabetes, allergic rhinitis, and primary biliary cholangitis. Alcohol at low-moderate dosages seems mostly to have a protective role in these diseases, while at higher dosages, the collateral risks surpass possible benefits. The specific mechanisms by which low-to-moderate alcohol intake relieves AD symptoms are not yet fully understood; however, emerging studies suggest that alcohol may have a systemic immunomodulatory effect, potentially altering the balance of anti-inflammatory innate and adaptive immune cells, as well as cytokines (via the NF-κB or NLRP3 pathways). It might influence the composition of the gut microbiome (increasing amounts of beneficial gut microbes) and the production of their fatty acid metabolites, such as short-chain fatty acids (SCFAs) and polyunsaturated fatty acids (PUFAs), as well as elevated concentrations of acetate, high-density lipoprotein (HDL), and nitric oxide (NO). Unfortunately, a definite acceptable daily intake (ADI) of ethanol is complicated to establish because of the many mechanisms associated with alcohol consumption such that despite the interesting content of these findings, there is a limit to their applicability and risks should be weighed in cases of alcoholic drinking recommendations. The aim of future studies should be to modulate those beneficial pathways involved in the alcohol-protective role of ADs with various strategies to avoid the risks associated with alcohol intake.

Connecting the Dots: Exploring the Association Between Systemic Lupus Erythematosus and Thyroid Disorders

Systemic lupus erythematosus (SLE) is a complex autoimmune disease marked by chronic inflammation and tissue damage that impacts multiple organ systems and diminishes the quality of life. Among the frequent comorbidities in SLE, thyroid dysfunction, including hypothyroidism and hyperthyroidism, stands out due to its high prevalence and common autoimmune basis. This review examines the epidemiological, genetic, and immunological factors that link SLE with autoimmune thyroid diseases such as Hashimoto's thyroiditis and Graves' disease. These overlapping mechanisms suggest a shared pathophysiological foundation that increases the risk of thyroid dysfunction in SLE patients. Clinically, distinguishing thyroid dysfunction from SLE symptoms, such as fatigue and cognitive difficulties, remains challenging, making regular thyroid screening in SLE patients essential. A multidisciplinary approach, bringing together rheumatologists and endocrinologists, is crucial to provide comprehensive care and improve outcomes for patients managing both conditions.

Autoimmunity's enigmatic role: exploring the connection with myalgic encephalomyelitis/chronic fatigue syndrome

BACKGROUND

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complicated, heterogeneous condition distinguished by post-exertional neuroimmune exhaustion and multisystem symptoms. Its complexity poses challenges for physicians, researchers and those inflicted by its presence. Due to conflicting evidence and limiting consensus, the association and contribution autoimmunity serves in the pathophysiology or aetiology of ME/CFS is yet to be confirmed. This systematic review synthesises the currently available data to clarify the role autoimmunity has in the pathogenesis of ME/CFS and explore the therapeutic limitations.

METHODS

This systematic review was conducted in accordance with the PRISMA and Cochrane guidelines. Full-text articles containing the primary key terms "Autoimmunity/Autoimmune" and "ME/CFS" were included provided their suitability to the inclusion and exclusion criteria.

RESULTS

Ten publications investigating the role of autoimmunity in ME/CFS were examined. One investigated the role of cytokine signalling; Three investigated the genetic nature of autoimmunity in ME/CFS patients; One examined the immune lineage of ME/CFS patients; Six investigated the presence and role of autoantibodies in ME/CFS patients.

CONCLUSION

The findings generated from this systematic review highlight inconsistent and insufficient evidence to classify ME/CFS as an autoimmune disease. Additionally, it further emphasises the complexity of ME/CFS and highlights the challenges in distinguishing autoreactivity from deregulatory processes. Future research is urgently needed to advance the development of diagnostic and treatment strategies.

PROSPERO REGISTRATION CODE

CRD42024533447.

Causal effects of post-traumatic stress disorder on autoimmune thyroid disease: insights from mendelian randomization

Objective

The relationship between post-traumatic stress disorder (PTSD) and autoimmune thyroid disease (AITD) needs further evaluation. This study employs Mendelian randomization (MR) to investigate the causal correlations of PTSD with autoimmune thyroiditis (AIT) and Graves' disease (GD).

Methods

Datasets for PTSD, AIT, and GD were obtained from FinnGen. The exposure-outcome causal relationship was assessed using inverse variance weighted, MR-Egger, and weighted median. Horizontal pleiotropy was evaluated through the MR-Egger intercept, heterogeneity was examined using Cochran's Q test, and robustness was assessed via leave-one-out sensitivity analysis.

Results

MR analysis indicated no significant causal relationship between PTSD and AIT (OR 0.920, 95% CI 0.832 to 1.017, p = 0.103), but a potential increase in the risk of GD associated with PTSD (OR 1.056, 95% CI 1.008 to 1.105, p = 0.021). MR-Egger intercept showed no horizontal pleiotropy (p > 0.05), and Cochran's Q showed no heterogeneity (p > 0.05). Sensitivity analysis suggested the MR results were robust.

Conclusions

Evidence of an MR association between genetic liability to PTSD and an increased risk of GD were provided, but no evidence of association between PTSD and AIT. The findings indicate that individuals with PTSD may have an increased likelihood of developing GD, underscoring the importance of further research to comprehend the intricate interplay between PTSD and thyroid disorders.

The Impact of Environmental Factors on the Development of Autoimmune Thyroiditis-Review

Autoimmune thyroiditis (Hashimoto's thyroiditis) is the most common autoimmune disease. It most often manifests itself as hypothyroidism but may also present with euthyroidism or even hyperthyroidism. The etiopathogenesis of autoimmune thyroiditis is still unclear. However, in addition to genetic and epigenetic factors, many environmental factors are known to increase the risk of developing AIT. In this review, we aimed to collect and analyze data connected with environmental factors and autoimmune thyroiditis development. Our review indicates iodine intake, vitamin D deficiency, selenium deficiency, viral infections caused by Epstein-Barr Virus (EBV), Human parvovirus B19 (PVB19), Human herpesvirus 6A (HHV-6A) and Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), bacterial infection caused by Helicobacter pylori, microbiome disruption, medications such as interferon-alpha and tyrosine kinase inhibitors, as well as stress, climate, and smoking can influence the risk of the occurrence of autoimmune thyroiditis. Having knowledge of risk factors allows for making changes to one's diet and lifestyle that will reduce the risk of developing the disease and alleviate the course of autoimmune thyroiditis.

The Role of the Immune System in the Course of Hashimoto's Thyroiditis: The Current State of Knowledge

The process of thyroid autoimmunization develops against the background of genetic predispositions associated with class II human leukocyte antigens (HLA-DR), as well as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), protein tyrosine phosphatase non-receptor type 22 (PTPN22), and forkhead transcription box protein P3 (FOXP3). Environmental factors, such as vitamin D deficiency, Zn, Se, and Mg, as well as infections, chronic stress, pregnancy, smoking, alcohol, medications, intestinal dysbiosis, and malnutrition, also play an important role. The first stage of autoimmunization involves the accumulation of macrophages and dendritic cells, as well as plasma cells. In the second stage, the mutual interactions of individual cells in the immune system lead to a decrease in the level of CD8+ in favor of CD4+, which intensifies the synthesis of T lymphocyte derivatives, especially Th1, Th17, Tfh, and Tc, reducing the level of Treg. Consequently, the number of the anti-inflammatory cytokines IL10 and IL2 decreases, and the synthesis of the pro-inflammatory cytokines IL-2, Il-12, Il-17, IL-21, IL-22, IFN-γ, and TNF-α increases. The latter two especially trigger the pyroptosis process involving the inflammasome. Activation of the inflammasome by IL-β and IL-18 produced by macrophages is one of the mechanisms of pyroptosis in the course of Hashimoto's thyroiditis, involving Gram-negative bacteria and NLRC4. In the next step, the apoptosis of thyroid cells is initiated by the intensification of perforin, granzyme, and proteoglycan synthesis by Tc and NK cells. The current findings raise many possibilities regarding interventions related to the inhibition of pro-inflammatory cytokines and the stimulation of anti-inflammatory cytokines produced by both T and B lymphocytes. Furthermore, since there is currently no effective method for treating thyroid autoimmunity, a summary of the review may provide answers regarding the treatment of not only Hashimoto's thyroiditis, but also other autoimmune diseases associated with autoimmunity.

Association Between Hashimoto's Thyroiditis and Rheumatoid Arthritis: A Bidirectional Mendelian Randomization Study

Background: We aim to investigate the possible causal association between Hashimoto's thyroiditis (HT) and rheumatoid arthritis (RA) using Mendelian randomization (MR) methods. Methods: A bidirectional MR analysis was conducted to evaluate the causal association between HT and RA. We obtained summary statistics data from two extensive genome-wide association studies (GWAS) comprising 15,654 cases of HT and 14,361 cases of RA. The primary effect estimate utilized in this study was the inverse-variance weighted (IVW) method. To ensure the reliability and stability of the results, we employed several additional methods for testing, including MR-Egger, weighted median, simple mode, weighted mode, and MR-PRESSO. Results: Our study revealed compelling evidence of bidirectional causality between HT and RA. When HT was considered as an exposure factor and RA was considered as an outcome factor, this study revealed a positive correlation between HT and RA (IVW: odds ratio [OR] = 2.4546, 95% confidence interval [CI], 1.1473-5.2512; p = 0.0207). Conversely, when we examined RA as the exposure factor and HT as the outcome factor, we still found a positive correlation between them (IVW: OR = 1.2113, 95% CI, 1.1248-1.3044; p = 3.9478 × 10-7). Conclusions: According to our research findings, there exists a bidirectional positive causal relationship between HT and RA among European populations. This implies that individuals with HT have an elevated risk of developing RA, and conversely, individuals with RA have an increased risk of developing HT.

From Antibodies to Artificial Intelligence: A Comprehensive Review of Diagnostic Challenges in Hashimoto's Thyroiditis

Hashimoto's thyroiditis (HT) poses diagnostic challenges due to its diverse clinical presentation and the intricacies of autoimmune thyroid diseases. This comprehensive narrative review explores the evolving landscape of diagnostic challenges in HT, aiming to provide a thorough understanding of the complexities involved in its diagnosis. The diagnostic criteria for HT involve a multifaceted approach, including clinical features, laboratory findings, and imaging studies. Serum antibodies against thyroid antigens, primarily thyroperoxidase (TPO) and thyroglobulin, play a crucial role in confirming the autoimmune nature of the disease. However, seronegative HT adds complexity by presenting without detectable antibodies. The significance of addressing diagnostic challenges lies in potential delays and misdiagnoses, emphasizing the need for accurate and timely intervention. The review explores future directions, emphasizing molecular and cellular aspects, genetic factors, and the emerging field of thyroid regeneration. Standardized diagnostic criteria are essential, considering the subjective nature of the current process. The heterogeneity of disease manifestations complicates targeted treatments, necessitating a deeper understanding of clinical presentations and underlying pathophysiology. Future research directions and challenges outlined in this review contribute to advancing our understanding and improving diagnostic precision in HT.

New Approach to Addison Disease: Oral Manifestations Due to Endocrine Dysfunction and Comorbidity Burden

This review highlights oral anomalies with major clinical impact in Addison disease (AD), including dental health and dermatologic features, through a dual perspective: pigmentation issues and AD comorbidities with oral manifestations. Affecting 92% of AD patients, cutaneomucosal hyperpigmentation is synchronous with or precedes general manifestations by up to a decade, underlying melanocytic infiltration of the basal epidermal layer; melanophages in the superficial dermis; and, rarely, acanthosis, perivascular lymphocytic infiltrate, and hyperkeratosis. Intraoral pigmentation might be the only sign of AD; thus, early recognition is mandatory, and biopsy is helpful in selected cases. The buccal area is the most affected location; other sites are palatine arches, lips, gums, and tongue. Pigmented oral lesions are patchy or diffuse; mostly asymptomatic; and occasionally accompanied by pain, itchiness, and burn-like lesions. Pigmented lingual patches are isolated or multiple, located on dorsal and lateral areas; fungiform pigmented papillae are also reported in AD individuals. Dermoscopy examination is particularly indicated for fungal etiology; yet, it is not routinely performed. AD’s comorbidity burden includes the cluster of autoimmune polyglandular syndrome (APS) type 1 underlying AIRE gene malfunction. Chronic cutaneomucosal candidiasis (CMC), including oral CMC, represents the first sign of APS1 in 70–80% of cases, displaying autoantibodies against interleukin (IL)-17A, IL-17F ± IL-22, and probably a high mucosal concentration of interferon (IFN)-γ. CMC is prone to systemic candidiasis, representing a procarcinogenic status due to Th17 cell anomalies. In APS1, the first cause of mortality is infections (24%), followed by oral and esophageal cancers (15%). Autoimmune hypoparathyroidism (HyP) is the earliest endocrine element in APS1; a combination of CMC by the age of 5 years and dental enamel hypoplasia (the most frequent dental complication of pediatric HyP) by the age of 15 is an indication for HyP assessment. Children with HyP might experience short dental roots, enamel opacities, hypodontia, and eruption dysfunctions. Copresence of APS-related type 1 diabetes mellitus (DM) enhances the risk of CMC, as well as periodontal disease (PD). Anemia-related mucosal pallor is related to DM, hypothyroidism, hypogonadism, corresponding gastroenterological diseases (Crohn’s disease also presents oral ulceration (OU), mucogingivitis, and a 2–3 times higher risk of PD; Biermer anemia might cause hyperpigmentation by itself), and rheumatologic diseases (lupus induces OU, honeycomb plaques, keratotic plaques, angular cheilitis, buccal petechial lesions, and PD). In more than half of the patients, associated vitiligo involves depigmentation of oral mucosa at different levels (palatal, gingival, alveolar, buccal mucosa, and lips). Celiac disease may manifest xerostomia, dry lips, OU, sialadenitis, recurrent aphthous stomatitis and dental enamel defects in children, a higher prevalence of caries and dentin sensitivity, and gingival bleeding. Oral pigmented lesions might provide a useful index of suspicion for AD in apparently healthy individuals, and thus an adrenocorticotropic hormone (ACTH) stimulation is useful. The spectrum of autoimmune AD comorbidities massively complicates the overall picture of oral manifestations.