Shared genetic relationships underlying generalized vitiligo and autoimmune thyroid disease

Combined tofacitinib citrate and 308-nm excimer laser treatment for vitiligo: a pilot study

BACKGROUND

Vitiligo is a clinically prevalent acquired skin disorder characterized by depigmentation. Currently, the therapeutic options for vitiligo are restricted, and numerous issues exist, such as a prolonged treatment course, unsatisfactory therapeutic efficacy, adverse reactions and a high propensity for recurrence after treatment cessation.

OBJECTIVES

To assess the safety and efficacy of combined treatment involving oral tofacitinib citrate (TC) and a 308-nm excimer laser (EL), with the aim of discovering a rapid and effective treatment approach to minimize the side-effects of various drugs.

METHODS

In total, 63 patients with progressive vitiligo and a Vitiligo Disease Activity Score of 4 from January 2022 to January 2024 were enrolled and divided into three groups. The three groups were: the TC combined with 308-nm EL and methylprednisolone treatment group (group 1); the TC and 308-nm EL treatment group (group 2); and the methylprednisolone alone treatment group (group 3). The treatment was continued for 24 weeks, and an assessment of therapy outcomes was performed.

RESULTS

When TC was combined with 308-nm EL and methylprednisolone treatment (group 1), the effect was more rapid than in the other two groups. When TC was combined with 308-nm EL (group 2), it had a more favourable treatment effect than that of methylprednisolone alone (group 3), despite having a slower onset of effect. After 24 weeks of treatment, there was no significant difference between group 1 and group 2 in terms of the total response rate or significant response. However, when only methylprednisolone treatment was applied, the effect was relatively slow and ineffective.

CONCLUSIONS

This study confirmed a rapid and effective treatment of vitiligo was achieved through a combination of TC and 308-nm EL. No serious adverse reactions were reported, and therefore this could potentially offer an optimal treatment plan for patients with vitiligo.

Skin Sceneries of Thyroid Disorders and Impact of Thyroid on Different Skin Diseases: A Scoping Review Focused on Pediatric Patients

Thyroid function plays a seminal role in the growth and development of children, and alterations in signaling pathways which interfere with the biosynthesis, transport, and metabolism of thyroid hormones might impact on the skin of such patients: this review explores the relationship between different thyroid disorders and dermatological manifestations with a particular focus on the pediatric population. Common cutaneous conditions associated with thyroid dysfunction may include chronic urticaria, vitiligo, and alopecia, which can be early harbingers of an underlying endocrine disruption. This review also highlights the growing cognizance of a "thyroid-skin axis", with thyroid hormones influencing many physiologic processes within the skin such as keratinocyte proliferation, hair growth, and epidermal differentiation. A precocious recognition of abnormal dermatological signs can be crucial in pediatric patients for a timely diagnosis before any development of complications and for personalized treatments of an underlying thyroid disorder, which can even be symptomless at an initial phase. Despite the lack of standardized guidelines for managing dermatologic manifestations occurring in thyroid diseases, a regular screening to identify endocrine dysfunction is recommended in those children who present chronic urticaria, vitiligo, or alopecia, though further research is needed to decipher mechanisms involved in the thyroid-skin partnership and develop more targeted management approaches.

Immune-Molecular Link between Thyroid and Skin Autoimmune Diseases: A Narrative Review

Autoimmune skin disorders, including Psoriasis, Lichen Planus, Vitiligo, Atopic Dermatitis, and Alopecia Areata, arise from a combination of genetic predisposition, external factors, and immunological dysfunction. It is well-documented that there is a strong correlation between autoimmune thyroid diseases and a range of dermatological disorders, especially urticaria. This review investigates possible links between autoimmune thyroiditis and a broader spectrum of autoimmune skin conditions, analyzing shared genetic markers, immunological mechanisms, and clinical correlations. Common pathogenic mechanisms include disrupted immune tolerance and oxidative stress, leading to chronic inflammation. Genetic factors, such as IL-23 receptor gene variants, increase the risk for Psoriasis, Alopecia Areata, and Hashimoto's thyroiditis. Additionally, CTLA-4 mutations enhance susceptibility to autoimmune thyroid and skin disorders. Shared genetic susceptibility was also reported in Lichen Planus and Vitilgo, even if different genetic loci might be involved. The breakdown of the immune system can determine a pro-inflammatory state, facilitating the development of autoimmunity and auto-antibody cross-reactions. The presence of similar antigens in skin cells and thyrocytes might explain why both tissues are affected. The significant overlap between these conditions emphasizes the necessity for a comprehensive diagnosis workup and treatment. Future research should focus on clarifying specific immunological pathways and identifying novel biomarkers.

Updates on the Association Between Vitiligo and Thyroid Diseases: A Systematic Review

The main objective of this study is to estimate the prevalence of thyroid diseases in patients with vitiligo and investigate the potential shared autoimmune mechanisms underlying the co-occurrence of vitiligo and thyroid diseases. To locate research that met the inclusion criteria, a thorough computerized search of relevant databases was carried out. A comprehensive search was carried out on PubMed, SCOPUS, Science Direct, and Web of Science to locate relevant material. Our data included 13 trials with 82,230 participants, and 40,116 (48.8%) of them were males. The prevalence of thyroid disorders ranged from 3.2% to 32.1%, with a total prevalence of 2,906 (3.5%). Vitiligo patients are more likely to have a number of immunological comorbidities, underscoring the serious effects of the illness on overall health, especially thyroid disorders. The correlation between vitiligo and positive thyroid peroxidase antibodies, hypothyroidism, and autoimmune thyroiditis is notably high. We found a strong association between vitiligo and the incidence of thyroid disorders, particularly autoimmune thyroid disorders. The findings emphasize the necessity of identifying and treating thyroid dysfunction in vitiligo patients, as it might affect the clinical course of the skin condition and overall patient health. Future research is required to standardize study methodology, investigate underlying mechanisms, and create integrated therapy and screening regimens.

The causal relationship between vitiligo and autoimmune thyroid diseases: A bidirectional two-sample Mendelian randomization analysis

BACKGROUND

Vitiligo is an acquired autoimmune depigmented disorder characterized by the presence of white and well-defined patches on the skin, mucous membrane, or both. It is associated with a significant disease burden and has a profoundly impacts patients' quality of life. Autoimmune thyroid diseases (AITDs) result from an autoimmune system dysregulation, leading to an erroneous immune attack on the thyroid gland. Previous observational and epidemiological studies have suggested the association between vitiligo and AITDs. However, the bidirectional cause-effect relationship between vitiligo and AITDs has not been formally assessed.

METHOD

Two-sample bidirectional Mendelian randomization (MR) analysis was conducted to explore potential causal relationships between genetically increased risk of vitiligo and AITDs, using summary statistics from genome-wide association studies in European populations. Causal effects were primarily estimated using the inverse variance weighted method, and additional quality control was performed using the MR-Egger, weighted median, simple mode, and weight mode methods. Sensitivity analysis was conducted to assess the robustness of the results.

RESULTS

The forward MR analysis showed a positive causal relationship between vitiligo and autoimmune thyroiditis (AIT), autoimmune hyperthyroidism (AIH), and Graves' disease (GD). The odds ratio (OR) were 1.17 (95% CI, 1.01-1.35; p = 0.04), 1.12 (95% CI, 1.03-1.22; p = 0.01), and 1.13 (95% CI, 1.06-1.20; p < 0.01), respectively. In the reverse MR analysis, a positive causal relationship was found between AIT and vitiligo, with an OR of 1.10 (95% CI, 1.01-1.35; p = 0.04). However, no causal relationship was observed between AIH (p = 0.10) or GD (p = 0.61) and vitiligo. Sensitivity analysis revealed no evidence of horizontal pleiotropy or heterogeneity.

CONCLUSIONS

The genetic-level investigation provides evidence of a genetic causal association between susceptibility to vitiligo and an increased risk of AITDs. Additionally, the results demonstrate a genetic causal association between susceptibility to AIT and an increased risk of vitiligo, while not indicating a similar association with susceptibility to AIH or GD.

Identification of Shared Biomarkers and Immune Infiltration Signatures between Vitiligo and Hashimoto's Thyroiditis

Background

Vitiligo and Hashimoto's thyroiditis (HT) are concomitant autoimmune diseases characterized by the destruction of melanocytes or thyrocytes. We aimed to explore the immunological mechanism of this comorbidity and screen their potential biomarkers.

Methods

We downloaded the microarray datasets from the GEO database. Differentially expressed genes (DEGs) and immune-related genes (IRGs) were selected. The immune-related differentially expressed genes (IRDEGs) were obtained by taking the intersection. Candidate biomarkers were elected by Cytoscape software. CIBERSORT was used to depict immune cell infiltration prospects. Correlation analysis was conducted between infiltrating cells and several indicators. The results were validated by real-time quantitative PCR (RT-qPCR).

Results

Three datasets and 60 IRDEGs were obtained in total. Pathway enrichment analysis showed that the T cell receptor signaling pathway, IL-17 signaling pathway, receptor-ligand activity, and signaling receptor activator activity were significantly enriched. We screened out four hub genes, including IFNG, STAT1, IL1B, and CXCL10. The ROC curve indicated the highest diagnostic value of CXCL10 in both vitiligo and HT. Immuno-infiltration analysis revealed significant changes in T cell subsets and macrophage subtypes, which were correlated with four hub genes, melanocyte markers, and thyroid-specific antigens. qPCR validated the hub genes in peripheral blood mononuclear cells from patients with comorbidity.

Conclusion

IFNG, STAT1, IL1B, and CXCL10, were the key IRDEGs to vitiligo and HT. These genes may participate in the comorbidity by remodeling the immune cell infiltration pattern, and cross-expressed antigens may mediate the common damage of melanocytes and thyroid tissues.

All-Cause and Cause-Specific Mortality among Patients with Vitiligo: A Nationwide Population-Based Study in Korea

Vitiligo is a common autoimmune skin disorder; however, there is limited information about risks of mortality among patients with vitiligo. Therefore, we aimed to investigate the mortality in patients with vitiligo. A population-based cohort study was conducted using the data linkage of the National Health Insurance Service database and the National Death Registry. Patients with incident vitiligo were matched with sociodemographic factors-matched controls without vitiligo in a 1:5 ratio. All-cause and cause-specific mortalities were compared between patients with vitiligo and controls. In total, 107,424 patients with incident vitiligo and 537,120 matched controls were included. The mortality rates were 34.8 and 45.3 per 10,000 person-years in patients and controls, respectively. Patients with vitiligo showed a significantly lower risk of mortality (adjusted hazard ratio = 0.75, 95% confidence interval = 0.72-0.78). The cause-specific mortality from infectious diseases, oncologic diseases, hematologic diseases, endocrine diseases, neurologic diseases, cardiovascular diseases, respiratory diseases, and renal/urogenital disease was significantly lower in patients with vitiligo. Patients with vitiligo were associated with a lower risk of mortality, suggesting that vitiligo-associated autoimmunity might contribute to reduced morbidity and mortality.

An extensive review of vitiligo-associated conditions

Vitiligo is an autoimmune disorder caused by the destruction of melanocytes in various body regions. Numerous diseases may accompany vitiligo. The prevalence of vitiligo varies among geographical regions and shows no relation to sex or age. However, vitiligo most commonly affects people aged 10 to 30 years. The clinical symptoms of vitiligo include irregular patches on the skin and various diseases associated with this disorder. The present review focuses on the clinical effects and risk factors of vitiligo-associated conditions and the current therapeutics for treating vitiligo. This systematic review was performed based on the PRISMA guidelines and articles published from 2000 to 2023 in several electronic databases (Web of Science, PubMed, PsycINFO, and others). The most clinically significant diseases associated with vitiligo are alopecia areata, autoimmune thyroid disease, Addison's disease, and type 1 diabetes mellitus. No targeted population is specifically prone to vitiligo; it does not affect any particular race or sex. Hence, awareness of the diseases associated with vitiligo is necessary to control them through various medical and surgical treatments with the proper facilities.

Vitiligo and Crohn's disease form an autoimmune cluster: insights from a population-based study

BACKGROUND

While the coexistence of vitiligo and Crohn's disease (CD) has been reported in individual patients, the epidemiological association between these autoimmune conditions remains inconclusive.

OBJECTIVE

To assess the bidirectional association between vitiligo and CD.

METHODS

A population-based study was performed to compare vitiligo patients (n = 20,851) with age-, sex- and ethnicity-matched control subjects (n = 102,475) regarding the incidence of new-onset and the prevalence of preexisting CD. Adjusted hazard ratios (HRs) and adjusted odds ratios (ORs) were calculated by multivariable Cox regression and logistic regression, respectively.

RESULTS

The incidence rate of new-onset CD was evaluated at 3.6 (95% CI, 2.7-4.9) cases per 10,000 person-years (PY) in patients with vitiligo and 2.4 (95% CI, 2.0-2.9) cases per 10,000 PY in controls. Patients with vitiligo experienced an elevated risk of CD (fully adjusted HR, 1.60; 95% CI, 1.10-2.34; p = 0.015). Congruently, a history of preexisting CD predicted elevated odds of having subsequent vitiligo (fully adjusted OR, 1.49; 95% CI, 1.15-1.93; p = 0.002). Compared to other patients with vitiligo, those with vitiligo and comorbid CD were older and had a higher prevalence of diabetes mellitus, hyperlipidemia, and hypertension but a comparable all-cause mortality rate.

CONCLUSIONS

The current study depicts a robust bidirectional association between vitiligo and CD. This knowledge is of clinical implication for physicians managing patients with both conditions. The diagnostic threshold for CD should be lowered in vitiligo patients with compatible symptoms.

Vitiligo Treatments: Review of Current Therapeutic Modalities and JAK Inhibitors

Vitiligo is a chronic autoimmune disease characterized by loss of pigment of the skin, affecting 0.5-2% of the population worldwide. It can have a significant impact on patients' quality of life. In recent years, there has been significant progress in our understanding of the pathogenesis of vitiligo. It is believed that vitiligo develops due to a complex combination of genetics, oxidative stress, inflammation, and environmental triggers. Conventional treatments include camouflage, topical corticosteroids, topical calcineurin inhibitors, oral corticosteroids, phototherapy, and surgical procedures, with the treatment regimen dependent on the patient's preferences and characteristics. With increased understanding of the importance of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway in the pathogenesis of vitiligo, treatment has expanded to include the first US FDA-approved cream to repigment patients with vitiligo. This review summarizes our understanding of the major mechanisms involved in the pathogenesis of vitiligo and its most common available treatments.

Fine Mapping Analysis of the MHC Region to Identify Variants Associated With Chinese Vitiligo and SLE and Association Across These Diseases

The important role of MHC in the pathogenesis of vitiligo and SLE has been confirmed in various populations. To map the most significant MHC variants associated with the risk of vitiligo and SLE, we conducted fine mapping analysis using 1117 vitiligo cases, 1046 SLE cases and 1693 healthy control subjects in the Han-MHC reference panel and 1000 Genomes Project phase 3. rs113465897 (P=1.03×10^-13, OR=1.64, 95%CI =1.44–1.87) and rs3129898 (P=4.21×10^-17, OR=1.93, 95%CI=1.66–2.25) were identified as being most strongly associated with vitiligo and SLE, respectively. Stepwise conditional analysis revealed additional independent signals at rs3130969(p=1.48×10^-7, OR=0.69, 95%CI=0.60–0.79), HLA-DPB1*03:01 (p=1.07×10^-6, OR=1.94, 95%CI=1.49–2.53) being linked to vitiligo and HLA-DQB1*0301 (P=4.53×10^-7, OR=0.62, 95%CI=0.52-0.75) to SLE. Considering that epidemiological studies have confirmed comorbidities of vitiligo and SLE, we used the GCTA tool to analyse the genetic correlation between these two diseases in the HLA region, the correlation coefficient was 0.79 (P=5.99×10^-10, SE=0.07), confirming their similar genetic backgrounds. Our findings highlight the value of the MHC region in vitiligo and SLE and provide a new perspective for comorbidities among autoimmune diseases.

The Immunogenetics of Vitiligo: An Approach Toward Revealing the Secret of Depigmentation

Vitiligo is a hypomelanotic skin disease and considered to be of autoimmune origin due to breaching of immunological self-tolerance, resulting in inappropriate immune responses against melanocytes. The development of vitiligo includes a strong heritable component. Different strategies ranging from linkage studies to genome-wide association studies are used to explore the genetic factors responsible for the disease. Several vitiligo loci containing the respective genes have been identified which contribute to vitiligo and genetic variants for some of the genes are still unknown. These genes include mainly the proteins that play a role in immune regulation and a few other genes important for apoptosis and regulation of melanocyte functions. Despite the available data on genetic variants and risk alleles which influence the biological processes, only few immunological pathways have been found responsible for all ranges of severity and clinical manifestations of vitiligo. However, studies have concluded that vitiligo is of autoimmune origin and manifests due to complex interactions in immune components and their inappropriate response toward melanocytes. The genes involved in the immune regulation and processing the melanocytes antigen and its presentation can serve as effective immune-therapeutics that can target specific immunological pathways involved in vitiligo. This chapter highlights those immune-regulatory genes involved in vitiligo susceptibility and loci identified to date and their implications in vitiligo pathogenesis.

Impact of cytotoxic T-lymphocyte-associated protein 4 codon 17 variant and expression on vitiligo risk

BACKGROUND

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is one of the essential brakes expressed on T cells that prevent T-cell hyperactivation-associated autoimmune disorders. Several CTLA4 polymorphisms were implicated in the regulation of gene expression. We aimed to explore the association of CTLA4 expression and rs231775 (c.49A>G) variant with vitiligo risk and severity of the disease in a sample of the Middle Eastern population.

METHODS

The CTLA4 gene expression and genotyping for rs231775 (A/G) variant were assessed in 161 vitiligo patients and 165 controls using a real-time polymerase chain reaction. Vitiligo Area Severity Index (VASI) and Vitiligo Disease Activity score (VIDA) were evaluated.

RESULTS

A higher frequency of rs231775 G allele was observed in vitiligo cases than controls (45% vs. 33%, p = 0.002). After adjustment of age, sex, family history of vitiligo, and CTLA expression level, using multivariate analysis, G/G carriers were associated with a higher risk of vitiligo under recessive (OR = 2.94, 95% CI = 1.61-5.35, p < 0.001), dominant (OR = 1.87, 95% CI = 1.14-3.06, p = 0.013), and homozygote comparison (OR = 3.34, 95% CI = 1.73-6.42, p = 0.001) models. Although the CTLA4 relative expression levels were comparable to that of controls, G/G carriers exhibited a significantly lower expression profile (median = 0.63, IQR = 0.34-1.75) than A/A (median = 1.43, IQR = 0.39-4.25, p = 0.018) and A/G carriers (median = 1.68, IQR = 0.49-3.92, p = 0.007). No significant associations of CTLA4 variant/expression with disease severity and/or activity were observed.

CONCLUSION

The CTLA4 rs231775 variant was associated with vitiligo susceptibility and gene expression; the risky genotype (GG) was associated with lower CTLA4 relative expression levels than the other genotypes. Further large-scale studies in different populations are warranted.

Correlation between gastrointestinal symptoms and adherence to traditional Persian medicine dietary recommendations in patients with vitiligo; a cross-sectional study

OBJECTIVES

Vitiligo is a chronic disease associated with the depigmentation of regions of the skin secondary to structural or functional damage to melanocytes. This damage results from interactions between the immune system and oxidative stress. In traditional Persian medicine (TPM), the concept of 'Barass' or 'Pissi' encompasses a group of skin diseases including vitiligo, for which there has been an emphasis on the preventive and therapeutic role of dietary modifications.

METHODS

In this cross-sectional study, 200 vitiligo patients and 200 controls were enrolled with a random sampling method. The participants included patients with vitiligo referred to the Dermatology Clinic of Shahid Faghihi Hospital (Shiraz, Iran), with the control group being comprised individuals who referred to this clinic for cosmetic purposes. Questionnaires comparing the severity of gastrointestinal symptoms and the rate of adherence to TPM dietary recommendations were filled by all participants. Data were analyzed using SPSS version 24.0.

RESULTS

The case group was significantly less adherent to TPM recommendations than the control group (8.25 ± 27.16 vs. 31.8 ± 10.47; p<0.001). However, there was no significant difference between both groups in the Gastrointestinal Symptom Rating Scale (GSRS) scores (14.09 ± 14.84 vs. 12.62 ± 11.71; p = 0.105). In the case group, the level of adherence to the recommendations of TPM was significantly lower among patients with lower education levels (R=-0.194; p=0.017). Furthermore, there was a significant negative relationship between the length of the disease and adherence to TPM dietary recommendations (R=-0.247; p=0.002).

CONCLUSIONS

In this study, the level of adherence to TPM recommendations was significantly lower among patients with vitiligo than the control group. Hence, further studies are suggested to identify the probable role of dietary habits in the pathogenesis of vitiligo.

Efficacy of Tacrolimus Versus Clobetasol in the Treatment of Vitiligo

Introduction Vitiligo is an acquired pigmentary disorder of the skin and mucous membranes which is characterized by circumscribed depigmented macules and patches. Vitiligo is a progressive disorder in which some or all of the melanocytes in the affected skin are selectively destroyed. Around 0.5-2% of the world population is affected by vitiligo and the average age of onset is 20 years. The objective of the study was to evaluate the efficacy of tacrolimus versus clobetasol in the treatment of vitiligo. It is an open randomized control trial conducted in the Department of Dermatology, Nishtar Hospital, Multan for six months.  Methods One hundred sixty-two patients of vitiligo were included in the study. The disease was diagnosed on basis of clinical features and the Standard Assessment scale proposed by Hossain which was used to monitor and grade the response. Patients were randomly allocated into two groups by lottery method having 81 patients in each group. Group A was given tacrolimus whereas Group B was given clobetasol. Patients were followed up every four weeks. On the 12^th week of treatment, effectiveness was assessed by measuring the Assessment scale proposed by Hossain. The results of the two groups were then compared. Results Sixty-three patients (38.9%) were males whereas 99 patients (61.1%) were females. The mean age of the patients included in the study was 29.68 + 8.162 years. The mean weight of the patients was 62.25 + 9.529 Kg. Out of 162, treatment was effective in 89 patients (54.9%) whereas in 73 patients (45.1%) the treatment was ineffective. In Group A (tacrolimus), 42 patients (51.9%) had effective treatment (on the complete resolution of symptoms) whereas 39 patients (48.1 %) had ineffective treatment. In Group B (clobetasol), 47 patients (58%) had effective treatment, and the rest (34, 42%) had ineffective treatment. A Chi-Square test was applied to compare the efficacy of the two groups. There was no statistically significant difference in both the groups in terms of efficacy. Group B was numerically superior in terms of effective treatment (47 versus 42) but not superior statistically. Conclusion Comparison of tacrolimus and clobetasol in patients of vitiligo showed no significant difference in the efficacy of the two groups. It can be concluded that tacrolimus may be considered superior to corticosteroids as its local and systemic adverse effects are less.

The effects of tacrolimus plus phototherapy in the treatment of vitiligo: a meta-analysis

The objective of this meta-analysis was performed to compare the effects of tacrolimus plus phototherapy in the treatment of patients with vitiligo. Relevant studies were identified by searching PubMed, Embase, and Web of Science databases. The main outcomes of interest included excellent response (≥ 75% repigmentation), good response (50-75% repigmentation), moderate response (25%-50% repigmentation), and poor response (< 25% repigmentation). Risk ratio (RR) with 95% confidence intervals (95% CIs) was used to calculate the data. Eleven studies were included in this study. Compared with phototherapy alone, combination treatment of tacrolimus and phototherapy significantly improved excellent response rate (RR = 1.40, 95% CI 1.16, 1.69; P < 0.001) and reduced the poor response rate (RR = 0.37, 95% CI 0.22, 0.61; P = 0.001). However, the good response rate (RR = 1.00, 95% CI 0.59, 1.69, P = 1.000) and moderate response rate (RR = 0.91, 95% CI 0.60, 1.38; P = 0.653) were not significantly different between the two treatments. Subgroup analysis suggested that combination treatment had a higher excellent response rate than phototherapy alone for lesions located in the face and proximal limbs. Both NB-UVB and EL, when added to tacrolimus, resulted in a significantly higher excellent response rate than they were used alone. Meta-regression analysis showed that age was a predictive factor that influenced the effect of combination treatment on an excellent response, in which children had a high excellent response to the treatment. Other demographic and clinical variables, including gender, disease duration, family history, and type of vitiligo, did not have any impact on the treatment effect. Combination treatment with tacrolimus and phototherapy was more effective than phototherapy monotherapy for patients with vitiligo, especially in the lesions located in the face and proximal limbs. More large-scale, well-performed trials are needed to verify our findings.

Identification of key genes and pathways involved in vitiligo development based on integrated analysis

Vitiligo is a chronic skin condition lack of melanocytes. However, researches on the aetiology and pathogenesis of vitiligo are still under debate. This study aimed to explore the key genes and pathways associated with occurrence and development of vitiligo.Weighted gene coexpression network analysis (WGCNA) was applied to reanalyze the gene expression dataset GSE65127 systematically. Functional enrichments of these modules were carried out at gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set variation analysis (GSVA), and gene set enrichment analysis (GSEA). Then, a map of regulatory network was delineated according to pivot analysis and drug prediction. In addition, hub genes and crucial pathways were validated by an independent dataset GSE75819. The expressions of hub genes in modules were also tested by quantitative real-time polymerase chain reaction (qRT-PCR).Eight coexpressed modules were identified by WGCNA based on 5794 differentially expressed genes of vitiligo. Three modules were found to be significantly correlated with Lesional, Peri-Lesional, and Non-Lesional, respectively. The persistent maladjusted genes included 269 upregulated genes and 82 downregulated genes. The enrichments showed module genes were implicated in immune response, p53 signaling pathway, etc. According to GSEA and GSVA, dysregulated pathways were activated incessantly from Non-Lesional to Peri-Lesional and then to Lesional, 4 of which were verified by an independent dataset GSE75819. Finally, 42 transcription factors and 228 drugs were spotted. Focusing on the persistent maladjusted genes, a map of regulatory network was delineated. Hub genes (CACTIN, DCTN1, GPR143, HADH, MRPL47, NKTR, NUF2) and transcription factors (ITGAV, SYK, PDPK1) were validated by an independent dataset GSE75819. In addition, hub genes (CACTIN, DCTN1, GPR143, MRPL47, NKTR) were also confirmed by qRT-PCR.The present study, at least, might provide an integrated and in-depth insight for exploring the underlying mechanism of vitiligo and predicting potential diagnostic biomarkers and therapeutic targets.

Vitiligo: A Review

Vitiligo, a common depigmenting skin disorder, has an estimated prevalence of 0.5–2% of the population worldwide. The disease is characterized by the selective loss of melanocytes which results in typical nonscaly, chalky-white macules. In recent years, considerable progress has been made in our understanding of the pathogenesis of vitiligo which is now clearly classified as an autoimmune disease. Vitiligo is often dismissed as a cosmetic problem, although its effects can be psychologically devastating, often with a considerable burden on daily life. In 2011, an international consensus classified segmental vitiligo separately from all other forms of vitiligo, and the term vitiligo was defined to designate all forms of nonsegmental vitiligo. This review summarizes the current knowledge on vitiligo and attempts to give an overview of the future in vitiligo treatment.

Cistanche deserticola polysaccharide induces melanogenesis in melanocytes and reduces oxidative stress via activating NRF2/HO-1 pathway

As a main part of pigmentation disorders, skin depigmentation diseases such as vitiligo and achromic naevus are very common and get more attention now. The pathogenesis of depigmentation includes melanocyte dysfunction and loss, which are possibly caused by heredity, autoimmunity and oxidative stress. Among them, oxidative stress plays a key role; however, few clinical treatments can deal with oxidative stress. As reported, Cistanche deserticola polysaccharide (CDP) is an effective antioxidant; based on that, we evaluated its role in melanocyte and further revealed the mechanisms. In this study, we found that CDP could promote melanogenesis in human epidermal melanocytes (HEMs) and mouse melanoma B16F10 cells, it also induced pigmentation in zebrafish. Furthermore, CDP could activate mitogen‐activated protein kinase (MAPK) signal pathway, then up‐regulated the expression of microphthalmia‐associated transcription factor (MITF) and downstream genes TYR, TRP1, TRP2 and RAB27A. Otherwise, we found that CDP could attenuate H₂O₂‐induced cytotoxicity and apoptosis in melanocytes. Further evidence revealed that CDP could enhance NRF2/HO‐1 antioxidant pathway and scavenge intracellular ROS. In summary, CDP can promote melanogenesis and prevent melanocytes from oxidative stress injury, suggesting that CDP helps maintain the normal status of melanocytes. Thus, CDP may be a novel drug for the treatment of depigmentation diseases.

The Use of Janus Kinase Inhibitors in Vitiligo: A Review of the Literature

Vitiligo is a common acquired depigmenting disorder characterized by the development of white macules and patches due to the loss of melanocytes. Patients with vitiligo can be stigmatized by society, making the disease a source of psychological stress that can considerably affect quality of life. The goal of vitiligo treatment is to obtain skin repigmentation in the majority of cases, and less commonly to depigment the remaining normal skin. There is no consistent, long-term, durable therapy for vitiligo for all patients, highlighting the unmet need for new safe and effective therapies to control this disease. Recently, JAK inhibitors have been explored as a promising novel treatment option in vitiligo. The JAK and signal transducers and activators of transcription (STAT) pathway is an attractive therapeutic target because IFN-γ-dependent cytokines produced through this pathway have been implicated in the pathogenesis of disease. This literature review describes vitiligo pathophysiology, explains the usefulness of the JAK inhibitors for treatment, and summarizes published case reports, case series, and open-label studies. Research outlined here shows JAK inhibitors in patients with vitiligo have a favorable safety profile and effectively produce repigmentation of lesions, especially with concomitant ultraviolet exposure. Additional studies are required to confirm efficacy, establish safety, and investigate durability of repigmentation.

Markedly Reduced Risk of Internal Malignancies in Patients With Vitiligo: A Nationwide Population-Based Cohort Study

PURPOSE

Recent studies indicated that the autoimmunity of vitiligo exerts effects on cells other than melanocytes, which confer reduced risks of both melanoma and nonmelanoma skin cancers in patients with vitiligo. However, the risk of internal malignancy in patients with vitiligo has not been elucidated.

PATIENTS AND METHODS

We conducted a population-based retrospective cohort study using data from the Korean National Health Insurance claims database obtained from January 2007 to December 2016. All patients age 20 years or older with vitiligo who had at least two contacts with a physician from 2009 to 2016, during which a principal diagnosis was made, were identified (vitiligo group). Controls were randomly selected (two per patient with vitiligo) after frequency matching with the vitiligo group for age and sex during the same period (control group).

RESULTS

A total of 101,078 patients with vitiligo and 202,156 controls without vitiligo were included. The incidence rates of internal malignancies were 612.9 and 708.9 per 100,000 person-years in the vitiligo and control groups, respectively. Patients with vitiligo showed a significantly reduced risk of overall internal malignancies (hazard ratio [HR], 0.86; 95% CI, 0.82 to 0.89; P < .001) compared with controls without vitiligo after adjustments for age, sex, and comorbidities. With regard to organ-specific malignancies, patients with vitiligo showed a remarkably decreased risk of cancer in the colon and rectum (HR, 0.62; 95% CI, 0.55 to 0.69; P < .001), ovary (HR, 0.62; 95% CI, 0.46 to 0.83; P < .001), and lung (HR, 0.75; 95% CI, 0.65 to 0.86; P < .001).

CONCLUSION

Vitiligo was associated with a reduced risk of overall internal malignancies. These findings suggest that autoimmune diseases, including vitiligo, may provide immune surveillance for the development of cancer beyond the targeted organ.

A Case of Oculocutaneous Albinism in a Patient with Hashimoto's Thyroiditis

BACKGROUND

Oculocutaneous albinism (OCA) is a heterogeneous autosomal recessive disorder characterized by reduced or absent melanin synthesis. Its prevalence is approximately one in 17,000 individuals worldwide. OCA causes a complete or partial absence of pigment in the skin, hair, and eyes. Reduction of melanin in the eyes results in reduced visual acuity, photophobia, and nystagmus. To our knowledge, the coexistence of albinism and thyroid autoimmune diseases has not been reported.

CASE REPORT

A 37-year-old male with OCA came to our observation for a familial history of autoimmune thyroiditis. He complained with mild asthenia. His brother was affected by OCA and autoimmune thyroiditis. Physical examination revealed the presence of fair skin, platinum white hair, and hypopigmentation of the iris. Laboratory data revealed the presence of subclinical hypothyroidism with positive serum anti-thyroid antibodies. Neck ultrasonography showed a markedly heterogeneously hypoechoic pattern of the thyroid, with a honeycomb-like appearance.

DISCUSSION

In the majority of cases, OCA in Caucasians is caused by mutations in the tyrosinase gene. The tyrosinase peptide is normally expressed on the surface of melanocytes, although recent studies have shown its presence in thyroid follicular epithelial cells of patients with Hashimoto's thyroiditis. Therefore, although the mechanism is unclear, the present case report may suggest a pathogenetic link between OCA and Hashimoto's thyroiditis.

Thyroid diseases and skin autoimmunity

The skin is the largest organ of the body, at the boundary with the outside environment. Primarily, it provides a physical and chemical barrier against external insults, but it can act also as immune organ because it contains a whole host of immune-competent cells of both the innate and the adaptive immune systems, which cooperate in eliminating invading pathogens following tissue injury. On the other hand, improper skin immune responses lead to autoimmune skin diseases (AISD), such as pemphigus, bullous pemphigoid, vitiligo, and alopecia. Although the interplay among genetic, epigenetic, and environmental factors has been shown to play a major role in AISD etiology and progression, the molecular mechanisms underlying disease development are far from being fully elucidated. In this context, epidemiological studies aimed at defining the association of different AISD with other autoimmune pathologies revealed possible shared molecular mechanism(s) responsible for disease progression. In particular, over the last decades, a number of reports have highlighted a significant association between thyroid diseases (TD), mainly autoimmune ones (AITD), and AISD. Here, we will recapitulate the epidemiology, clinical manifestations, and pathogenesis of the main AISD, and we will summarize the epidemiological evidence showing the associations with TD as well as possible molecular mechanism(s) underlying TD and AISD pathological manifestations.

Factors Associated with Development of Vitiligo in Patients with Halo Nevus

Background:

Halo nevus (HN) has been shown to be associated with vitiligo, but no standard signs are currently available to identify HN patients at risk of vitiligo, and the relevant data obtained in previous studies are somewhat conflicting. This study aimed to identify factors affecting the presence of vitiligo in HN patients.

Methods:

We performed a retrospective study on consecutive patients with HN at the First Affiliated Hospital of Sun Yat-sen University between January 2011 and December 2016. Detailed demographic and clinical data were collected to identify the factors associated with the presence of vitiligo in this cohort of patients using uni- and multi-variate logistic regression analyses.

Results:

A total of 212 HN patients were included, 101 of whom had vitiligo-associated HN (HNV). Univariate analysis indicated that a personal history of thyroid diseases was positively associated with HNV (odds ratio [OR] = 10.761, P = 0.025), while the onset age of HN was negatively associated with HNV (OR = 0.537, P = 0.026). Multivariate analysis demonstrated that the Koebner phenomenon (KP; OR = 10.632, P < 0.0001), multiple HN (OR = 3.918, P < 0.0001), and a familial history of vitiligo (OR = 3.222, P = 0.014) were independent factors associated with HNV.

Conclusions:

HN without vitiligo has clinical features distinct from HN associated with vitiligo. HN patients with KP, multiple lesions, or familial history of vitiligo are more likely to develop vitiligo and therefore should be monitored for clinical signs of such accompanied conditions.

Comorbidities in vitiligo: comprehensive review

Vitiligo is a common skin disorder characterized by idiopathic, progressive cutaneous hypomelanosis. Vitiligo is associated with several comorbid autoimmune, systemic, and dermatological diseases, primarily thyroid disease, alopecia areata, diabetes mellitus, pernicious anemia, systemic lupus erythematosus, rheumatoid arthritis, Addison's disease, inflammatory bowel disease, Sjögren's syndrome, dermatomyositis, scleroderma, ocular and audiological abnormalities, psoriasis, and atopic dermatitis. It is essential to increase awareness of these comorbidities in order to improve the disease burden and quality of life of patients with vitiligo. Herein, we review the association with the most frequent comorbidities associated with vitiligo.

Clinical and Molecular Aspects of Vitiligo Treatments

Vitiligo is an asymptomatic but cosmetically disfiguring disorder that results in the formation of depigmented patches on skin and/or mucosae. Vitiligo can be segmental or non-segmental depending upon the morphology of the clinical involvement. It can also be classified as progressing or stable based on the activity of the disease. Further, the extent of involvement can be limited (localized disease) or extensive (generalized disease). The treatment of vitiligo therefore depends on the clinical classification/characteristics of the disease and usually comprises of 2 strategies. The first involves arresting the progression of active disease (to provide stability) in order to limit the area involved by depigmentation. The second strategy aims at repigmentation of the depigmented area. It is also important to maintain the disease in a stable phase and to prevent relapse. Accordingly, a holistic treatment approach for vitiligo should be individualistic and should take care of all these considerations. In this review, we shall discuss the vitiligo treatments and their important clinical and molecular aspects.

The Prevalence of Thyroid Disorders in Patients With Vitiligo: A Systematic Review and Meta-Analysis

Background: Associations between vitiligo and thyroid disorders have been suggested, However, the prevalence of thyroid disorders in vitiligo vary widely. Purpose: To conduct a systematic review and meta-analysis assessing the prevalence of thyroid disorders in patients with vitiligo. Method: The PubMed, Cochrane Library, EMBASE, CNKI (China National Knowledge Infrastructure), Chongqing VIP database, and Wanfang database from inception to August 2, 2018 were systematically searched. The pooled prevalence and its 95% confidence interval (CI) were calculated. Results: A total of 77 eligible studies were identified and included, published from 1968 to 2018. Six thyroid disorders including subclinical hyperthyroidism, overt hyperthyroidism, subclinical hypothyroidism, overt hypothyroidism, Graves disease, and Hashimoto thyroiditis were described. The numbers of relative studies were 54 in overt hypothyroidism, 50 in overt hyperthyroidism, 25 in subclinical hypothyroidism, 19 in Hashimoto thyroiditis, 16 in Graves disease, and 10 in subclinical hyperthyroidism. The highest prevalence was 0.06 (95% CI: 0.04-0.07) in subclinical hypothyroidism, and the lowest was 0.01 in subclinical hyperthyroidism (95% CI: 0.00-0.01) or Graves disease (95% CI: 0.01-0.02). Conclusion: Six thyroid disorders showed various prevalence in vitiligo. The highest prevalence was in subclinical hypothyroidism, and the lowest was in subclinical hyperthyroidism or Graves disease. Screening vitiligo patients for thyroid disorders seem plausible, in an effort to detect potential thyroid diseases or to assess the risk of future onset.

Quality of Life, Burden of Disease, Co-morbidities, and Systemic Effects in Vitiligo Patients

Vitiligo is a complex, systemic disease associated with many autoimmune and autoinflammatory conditions. Additionally, the cutaneous changes of vitiligo have significant effects on quality of life and self-esteem. Further efforts are needed to increase our understanding of vitiligo comorbidities as well as to increase awareness of the psychological effects of vitiligo.

A holistic review on the autoimmune disease vitiligo with emphasis on the causal factors

Vitiligo is an idiopathic systemic autoimmune disease affecting skin, hair and oral mucosa. This genetic yet acquired disease characterized by melanin loss is a cause of morbidity across all races. Though thyroid disturbance has been recognized as a key trigger of this pathology, an array of other factors plays critical role in its manifestation. Multiple hormones (corticotropin-releasing hormone, adrenocorticotropic hormone, α-melanocyte-stimulating hormone, melatonin, calcitriol, testosterone, estrogen), genes (Human leukocyte antigen (HLA), Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), Forkhead box D3 (FOXD3), Cluster of differentiation 117 (CD117), Estrogen receptor (ESR) 1, Cyclooxygenase-2 (COX2), Vitiligo-associated protein 1 (VIT1)), and lifestyle choices (stress, diet, cosmetic products, and medications) have been suspected as drivers of this disorder. The pathological mechanisms have been understood in recent times, with the aid of genomic studies; however a universally-effective therapy is yet to be achieved. This review discusses these under-investigated facets of vitiligo onset and progression; hence, it is expected to enrich vitiligo research.

MicroRNA-211 Regulates Oxidative Phosphorylation and Energy Metabolism in Human Vitiligo

Vitiligo is a common chronic skin disorder characterized by loss of epidermal melanocytes and progressive depigmentation. Vitiligo has complex immune, genetic, environmental, and biochemical causes, but the exact molecular mechanisms of vitiligo development and progression, particularly those related to metabolic control, are poorly understood. In this study we characterized the human vitiligo cell line PIG3V and the normal human melanocyte line HEM-l by RNA sequencing, targeted metabolomics, and shotgun lipidomics. Melanocyte-enriched microRNA-211, a known metabolic switch in nonpigmented melanoma cells, was severely down-regulated in vitiligo cell line PIG3V and skin biopsy samples from vitiligo patients, whereas its predicted targets PPARGC1A, RRM2, and TAOK1 were reciprocally up-regulated. microRNA-211 binds to PGC1-α 3' untranslated region locus and represses it. Although mitochondrial numbers were constant, mitochondrial complexes I, II, and IV and respiratory responses were defective in vitiligo cells. Nanoparticle-coated microRNA-211 partially augmented the oxygen consumption rate in PIG3V cells. The lower oxygen consumption rate, changes in lipid and metabolite profiles, and increased reactive oxygen species production observed in vitiligo cells appear to be partly due to abnormal regulation of microRNA-211 and its target genes. These genes represent potential biomarkers and therapeutic targets in human vitiligo.

Vitiligo and Autoimmune Thyroid Disorders

Vitiligo represents the most common cause of acquired skin, hair, and oral depigmentation, affecting 0.5-1% of the population worldwide. It is clinically characterized by the appearance of disfiguring circumscribed skin macules following melanocyte destruction by autoreactive cytotoxic T lymphocytes. Patients affected by vitiligo usually show a poorer quality of life and are more likely to suffer from depressive symptoms, particularly evident in dark-skinned individuals. Although vitiligo is a non-fatal disease, exposure of affected skin to UV light increases the chance of skin irritation and predisposes to skin cancer. In addition, vitiligo has been associated with other rare systemic disorders due to the presence of melanocytes in other body districts, such as in eyes, auditory, nervous, and cardiac tissues, where melanocytes are thought to have roles different from that played in the skin. Several pathogenetic models have been proposed to explain vitiligo onset and progression, but clinical and experimental findings point mainly to the autoimmune hypothesis as the most qualified one. In this context, it is of relevance the strong association of vitiligo with other autoimmune diseases, in particular with autoimmune thyroid disorders, such as Hashimoto thyroiditis and Graves' disease. In this review, after a brief overview of vitiligo and its pathogenesis, we will describe the clinical association between vitiligo and autoimmune thyroid disorders and discuss the possible underlying molecular mechanism(s).

Thyroid abnormalities in paediatric patients with vitiligo: retrospective study

INTRODUCTION

The association between vitiligo and thyroid disease is not fully investigated especially in paediatric patients.

AIM

To determine the incidence of vitiligo and thyroid disorders in children. This is the first report from middle Anatolia and the second report from Turkey.

MATERIAL AND METHODS

A retrospective chart review was performed to examine the presence of thyroid abnormalities in paediatric patients who had been admitted to the dermatology department with vitiligo.

RESULTS

A total of 155 paediatric patients, including 80 (52%) male and 75 (48%) female patients were included. The mean age was 8.6 years. Non segmental vitiligo was the most common type of the disease in 140 (90%) reviewed patients, while segmental vitiligo appeared only in 15 (10%) patients. The mean onset of vitiligo was 5.6 ±0.9 years. A family history of vitiligo was found in 14 (9%) children. Thirty-four (22%) patients had thyroid function tests and/or thyroid autoantibody abnormality. All of these patients had non segmental vitiligo. It was statistically significant (p < 0.05) in types of vitiligo and thyroid disease parameters.

CONCLUSIONS

Our results show that it may be useful to screen thyroid in children with non segmental vitiligo.

Alternative Systemic Treatments for Vitiligo: A Review

Vitiligo is a common, acquired disorder of skin pigmentation that can significantly impact quality of life. It often represents a therapeutic challenge, which has resulted in interest in alternative treatments such as herbal and vitamin supplements. In this review, we provide an overview of the most commonly studied complementary agents, describe proposed mechanisms of action, identify potential adverse effects, and discuss the primary evidence supporting their use. Our discussion focuses on L-phenylalanine, Polypodium leucotomos, khellin, Ginkgo biloba, and vitamins and minerals, including vitamins B12, C, and E, folic acid, and zinc used as monotherapy or in combination with other treatments for the management of vitiligo.

A novel FoxD3 Variant Is Associated With Vitiligo and Elevated Thyroid Auto-Antibodies

CONTEXT

Vitiligo frequently coincides with autoimmune endocrinopathies, particularly Hashimoto's thyroiditis (HT). Genetic susceptibility may underlie this coincident occurrence. One candidate region is the autoimmunity susceptibility locus on chromosome 1, which encompasses forkhead transcription factor D3 (FoxD3), a gene involved in embryonal melanogenesis. We identified a promotor variant (rs78645479) in an index case of vitiligo + HT + candidiasis and evaluated its clinical and functional relevance.

DESIGN

We genotyped 281 patients with variable autoimmune endocrinopathies: HT, Graves' disease (GD), type 1 diabetes (T1D), Addison's disease (AD), autoimmune polyglandular syndrome (APS), and/or vitiligo and 1858 controls. Furthermore, we experimentally assessed the effect of the variant on promotor activity and assessed the expression of FoxD3 in human thyroid tissue samples.

RESULTS

Patients with vitiligo had a higher frequency of the risk allele (30%) compared with healthy controls (18.2%). In addition, the variant was associated with the incidence of elevated anti-TPO antibodies and anti-Tg antibodies, but not with TSH, FT3, or FT4 levels and also not with GD, T1D, AD, or APS. Functionally, the variant increased transcriptional activity in Jurkat and in Hek293 cells. We confirmed gene expression of FoxD3 in human thyroid tissue, which seemed elevated in thyroid tissue samples of some patients with GD and nonautoimmune goiter but not in patients with HT.

CONCLUSION

In addition to a possible association of rs78645479 in FoxD3 with vitiligo, our data on the association of this FoxD3 variant with thyroid autoantibodies suggest a potential involvement of FoxD3 in thyroid immunoregulation.

Current Management of Pediatric Vitiligo

Vitiligo is a common inflammatory disorder with worldwide prevalence of 0.4-2 % of the population, with half of cases beginning in childhood. The management of childhood vitiligo should be tailored to avoid negative effects on the overall growth and psychological development of the patient. Therapy of vitiligo in childhood is chosen based on the location of the lesions, lesion age, and extent of lesions in the context of the child's age and the developmental status of the child. There are four age categories in childhood vitiligo: [1] infantile and toddler (rare) (ages 0-3 years), [2] ages 4-8 years, [3] ages 9-12 years, and [4] 13+ years of age, based on developmental stage, psychological maturation, and ability to comply or participate in therapy. These categories are also differentiated psychologically by susceptibility to bullying, self-image development, and personal concern with lesion appearance, which increases with time. Intervention is advisable in cases with facial and leg involvement due to prominence of lesions and cosmetic defect. Medical interventions are largely the usage of topical therapies including corticosteroids and calcineurin inhibitors, some vitamin therapy (oral and topical vitamin D), and judicious introduction of phototherapy sources based on age and severity. Screening and appropriate subspecialist referral for co-morbidities (e.g., thyroid disease, celiac disease, psychological distress, and vitamin D deficiency) may enhance overall health. Cosmesis and camouflage are generally safe in childhood and have been noted to improve overall quality of life in this grouping. Genetic transmission of vitiligo is minimal at 5-6 % in first-degree relatives. This article reviews the therapeutics of pediatric vitiligo from the perspective of developmental stages and response to therapy.

Vitiligo

Vitiligo, an acquired pigmentary disorder of unknown origin, is the most frequent cause of depigmentation worldwide, with an estimated prevalence of 1%. The disorder can be psychologically devastating and stigmatising, especially in dark skinned individuals. Vitiligo is clinically characterised by the development of white macules due to the loss of functioning melanocytes in the skin or hair, or both. Two forms of the disease are well recognised: segmental and non-segmental vitiligo (the commonest form). To distinguish between these two forms is of prime importance because therapeutic options and prognosis are quite different. The importance of early treatment and understanding of the profound psychosocial effect of vitiligo will be emphasised throughout this Seminar.

A genetic risk score for thyroid peroxidase antibodies associates with clinical thyroid disease in community-based populations

CONTEXT

Antibodies against thyroid peroxidase (TPOAbs) are detected in 90% of all patients with Hashimoto thyroiditis, the most common cause of hypothyroidism. Hypothyroidism is associated with a range of adverse outcomes. The current knowledge of its genetic underpinnings is limited.

OBJECTIVE

The purpose of this study was to identify novel genetic variants associated with TPOAb concentrations and positivity using genome-wide association data and to characterize their association with thyroid function and disease.

DESIGN, SETTING, AND PARTICIPANTS

We studied European ancestry participants of 3 independent prospective population-based studies: Atherosclerosis Risk In Communities study (n = 7524), Study of Health in Pomerania (n = 3803), and Study of Health in Pomerania-TREND (n = 887).

EXPOSURE

Single nucleotide polymorphisms (SNPs), individually and combined into a genetic risk score (GRS), were examined.

MAIN OUTCOMES

The main outcomes were TPOAb concentrations and positivity, thyroid hormone concentrations (TSH, free T4), and clinical thyroid diseases (subclinical and overt hypothyroidism and goiter).

RESULTS

Significantly associated single nucleotide polymorphisms (P < 5 · 10(-8)) mapped into 4 genomic regions not previously implicated for TPOAbs (RERE, extended HLA region) and into 5 previously described loci. A higher Genetic Risk Score (GRS) based on these 9 SNPs showed strong and graded associations with higher TPOAb, TSH, and lower free T4 concentrations (P < .001). Compared with individuals in the lowest GRS quartile, those in the highest quartile had 1.80-fold higher odds of subclinical hypothyroidism (95% confidence interval, 1.27-2.55) and 1.89-fold higher odds of overt hypothyroidism (95% confidence interval, 1.24-2.87).

CONCLUSION

The identification of 4 novel genetic loci associated with TPOAb concentrations and positivity gives further insight into the genetic underpinnings of hypothyroidism. A GRS showed strong and graded associations with markers of thyroid function and disease in independent population-based studies.

Prevalence of vitiligo and associated comorbidities in Korea

PURPOSE

Vitiligo prevalence and its associated comorbidities rate have been reported variably among different populations. We aimed to determine the prevalence of vitiligo in Korea along with the baseline rate of comorbidities and compared the risks to the general population using hospital visit information of the total population in Korea.

MATERIALS AND METHODS

We assessed demographic characteristics of vitiligo patients in Korean population from 2009 to 2011 in a nationwide data from Health Insurance Review Assessment Service. Patients who had at least one visit to Korea's primary, secondary, or tertiary referral hospitals with International Classification of Diseases, 10th Revision, Clinical Modification diagnosis code for vitiligo were identified. As a supplementary study, comorbidities associated with vitiligo were selected for further review to calculate relative risks compared to the general population.

RESULTS

The annual prevalence of vitiligo determined by hospital-visiting rate in Korea was 0.12% to 0.13% over a three year period. In sync with other previous epidemiological studies, there was bimodal distribution among the age groups and no difference between genders. Also, vitiligo in Korean population was associated with various autoimmune/non-autoimmune diseases such as thyroiditis, atopic dermatitis, and psoriasis.

CONCLUSION

This study was by far the most comprehensive review on prevalence of vitiligo using a data of total population in Korea. The prevalence is within a range of those reported in previous literatures, and increased risk of comorbidities such as thyroid diseases and psoriasis in vitiligo might aid clinicians in the initial work up of vitiligo patients and concurrent follow ups.

The angiotensin-converting enzyme gene insertion/deletion polymorphism in Indian patients with vitiligo: a case-control study and meta-analysis

BACKGROUND

Vitiligo is a common, acquired, idiopathic depigmenting skin disorder. Although the exact pathogenesis remains unknown, genetic susceptibility and autoimmune responses play a role in vitiligo development. Previous studies have suggested that the D allele of the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is associated with vitiligo in Indians and Koreans. Furthermore, significantly higher serum ACE levels have been demonstrated in patients with some autoimmune and autoinflammatory disorders.

OBJECTIVES

The objectives were to investigate any association between the ACE I/D polymorphism and vitiligo susceptibility in an Indian population, and to compare serum ACE levels in patients with vitiligo and healthy subjects.

METHODS

The ACE I/D genotypes of 79 patients with vitiligo and 100 normal individuals were determined by polymerase chain reaction amplification. A meta-analysis was done to compare the distribution of the ACE I/D alleles and genotypes in the current and three previous studies. Serum ACE levels were evaluated by enzyme-linked immunosorbent assay.

RESULTS

A significant increase in the frequency of the ACE I/D D allele was evident in patients with vitiligo in both the case-control study [P=0·005; odds ratio (OR) 1·87; 95% confidence intervals (CI) 1·22-2·85] and the meta-analysis (P=0·044; OR 1·44; 95% CI 1·01-2·06). Serum ACE levels were significantly increased in patients with vitiligo compared with healthy subjects (P<0·0001).

CONCLUSIONS

In agreement with earlier reports, the ACE I/D D allele is associated with vitiligo susceptibility in the Indian population. The significantly elevated serum ACE levels in our cohort of patients with vitiligo concur with those previously found in patients with some other autoimmune diseases.

High prevalence of autoimmune thyroiditis in children and adolescents with vitiligo

BACKGROUND/AIMS

Vitiligo is considered to be an autoimmune disease and is known to be associated with other autoimmune diseases, particularly affecting the thyroid. In children and adolescents this association has been reported in only a few studies, with varying results. The aim of this study was to examine thyroid function and prevalence of thyroid autoimmunity in children and adolescents with vitiligo and to investigate the utility of screening.

METHODS

Two hundred and sixty patients with vitiligo were enrolled. Plasma TSH, FT4 and anti-thyroid peroxidase (TPO) antibody concentrations were measured. The prevalence of thyroid dysfunction and autoimmunity were compared to the general healthy paediatric population.

RESULTS

Autoimmune thyroiditis (AIT) with thyroid hormone disturbances was diagnosed in 16 patients (6.2%). This is significantly higher than the prevalence reported in the general healthy paediatric population. Increased levels of anti-TPO antibodies (= 30 kU/l), without thyroid hormone disturbances, were found in 27 patients (10.5%).

CONCLUSION

The prevalence of AIT in children and adolescents with vitiligo is significantly higher than in the general population. It may be advantageous to screen thyroid function and antibody levels in all paediatric patients with non-segmental vitiligo. To strengthen recommendations on screening, research on the burden for patients and cost-effectiveness is needed.

Polymorphisms in NLRP1 gene and susceptibility to autoimmune thyroid disease

The autoimmune thyroid disorders, or AITDs, comprise 2 related disorders, Graves' disease and Hashimoto thyroiditis. In AITD, immune system produces antibodies against autothyroid antigens. The etiology of AITDs involves a complex interaction between genetic predisposing factors and environmental triggering factors. Variations in NACHT leucine-rich repeat protein 1(NLRP1) gene a key regulator of the innate immunity have been shown to confer risk for vitiligo and several autoimmune diseases. In this study we hypothesize that variants in NLRP1 gene might be involved in the susceptibility to autoimmune thyroid disease. Five single nucleotide polymorphisms (SNPs) in NLRP1 were genotyped in 207 AITD patients and 220 normal controls. We found that NLRP1 rs12150220 T allele (OR = 1.273, 95% CI: 0.971-1.670, p = 0.040) and NLRP1 rs2670660 G allele (OR = 1.264, 95% CI: 0.965-1.656, p = 0.044) were significantly associated with AITD compared with controls. These results suggest that NLRP1 may be involved in the pathogenesis of AITD.

Vitiligo road map

Vitiligo is a depigmenting disorder stemming from melanocyte loss or dysfunction. It has a complex, multifaceted etiology. We constructed a "vitiligo road map," consisting of basic science, clinical, and treatment components, in order to better portray our current understanding of vitiligo pathogenesis and reflect upon novel biomarkers and therapeutic targets for future research. The melanocyte map elaborates on the molecular processes and intracellular signaling pathways initiated by various external autocrine/paracrine factors in representing normal melanocyte homeostatic functions modulating its viability, proliferation, differentiation, dendricity, migration, and melanogenic processes. This vitiligo map identifies known inducers/triggers of vitiligo onset and progression that cultivate a microenvironment for melanocyte disappearance, real or functional. This map describes the molecular mechanisms of currently utilized clinical and experimental treatments of vitiligo that facilitate repigmentation.

The immunopathogenesis of chronic autoimmune thyroiditis one century after hashimoto

Hakaru Hashimoto described 4 patients with a hitherto unknown cause for goitre, struma lymphomatosa, a century ago. He was careful to distinguish this from Riedel thyroiditis but it has become clear that fibrosis and atrophy of the thyroid are indeed components of Hashimoto thyroiditis, and in rare cases IgG4-related sclerosing disease may be an outcome. Although the cause of the lymphocytic infiltration was unknown to Hashimoto, we now know through the pioneering studies of N.R. Rose and E. Witebsky [J Immunol 1956;76:417-427] that this condition is the archetype for autoimmune destruction as a disease mechanism. In the last two decades in particular, there has been huge interest in unravelling the genetic basis for this and related autoimmune disorders. The list of polymorphisms associated with autoimmune thyroid disease grows each year, and in the case of vitiligo, which is frequently found in association with thyroid autoimmunity, we know that 27 separate susceptibility loci account for less than 20% of the heritability of this condition. Environmental and existential factors may turn out to be just as complex in number and in interactions. We can thus imagine a 'Swiss cheese' model for the causation of autoimmune thyroid disease, in which the effects of cumulative weaknesses line up - like the holes in slices of cheese - to allow the catastrophic event of autoimmune destruction to occur.

Potential role of neurogenic inflammatory factors in the pathogenesis of vitiligo

BACKGROUND

Vitiligo is a highly complex multifactorial condition of the skin that has an unclear mechanism of pathogenesis.

OBJECTIVE

This review summarizes the role of various neurogenic inflammatory factors significantly upregulated in vitiligo.

METHODS

A literature review was conducted of all pertinent data regarding neuropeptides that are altered in vitiligo and their possible role in the destruction of melanocytes.

RESULTS

The close associations between the skin, immune system, and nervous system, along with specific changes demonstrated in vitiligo patients, support a pathogenic mechanism of vitiligo that involves neuroimmunologic factors, the release of which can be governed by mental stress.

CONCLUSION

Neuropeptides and nerve growth factors are critical regulators of emotional response and may precipitate the onset and development of vitiligo in certain predisposed individuals. More studies are required to investigate whether a direct link exists between genetics, mental stress, and neurogenic factors in vitiligo.

The prevalence of thyroid disease in patients with vitiligo: a systematic review

BACKGROUND

Thyroid disease has been suggested to be associated with vitiligo. However, the outcomes of prevalence studies on thyroid disease in vitiligo vary widely.

OBJECTIVES

To summarize and critically appraise current evidence of the prevalence of thyroid diseases in vitiligo.

METHODS

A systematic review was performed searching the electronic databases OVID MEDLINE, OVID EMBASE and PubMed. Guidelines for the critical appraisal of studies on prevalence of a health problem were adapted to evaluate the methodological quality of the included studies. Results were analysed in a meta-analysis with a risk ratio (RR).

RESULTS

Forty-eight studies published between 1968 and 2012 met the inclusion criteria. Most of the studies (50%) were of fair methodological quality, whereas 18 studies (38%) were of poor quality and six studies (12%) were of good quality. Thyroid disease, autoimmune thyroid disease and presence of thyroid-specific autoantibodies showed a mean prevalence of, respectively, 15·1%, 14·3% and 20·8% in patients with vitiligo and an RR of, respectively, 1·9, 2·5 and 5·2 (all statistically significant). This review shows an increased prevalence and an increased risk of (autoimmune) thyroid disease in patients with vitiligo compared with nonvitiligo. This risk seems to increase with age.

CONCLUSIONS

Clinicians should be aware of this increased risk in patients with vitiligo and should be attentive for symptoms of thyroid disease. To make recommendations on screening for thyroid disease in patients with vitiligo future research of good methodological quality, including differentiation of vitiligo types and the use of standardized outcome measures, is needed.

Autoimmune thyroid disease in patients with vitiligo: prevalence study in India

OBJECTIVE

To identify the prevalence of autoimmune thyroid disease (AITD) in Asian Indian patients with vitiligo and to compare the clinical profile between thyroid peroxidase (TPO) antibody-positive and TPO antibody-negative groups.

METHODS

In this cross-sectional, case-controlled study, 50 patients with vitiligo (29 women and 21 men) were included. Patients with previous disorders, irradiation, or surgical procedures involving the thyroid were excluded from the study. All participants underwent a complete physical examination, and a single fasting blood sample was analyzed for thyroid function (triiodothyronine, thyroxine, thyroid-stimulating hormone, and TPO and thyroglobulin antibodies), inflammatory and immunologic markers (erythrocyte sedimentation rate, C-reactive protein, and rheumatoid factor), and serum calcium, phosphorus, and alkaline phosphatase concentrations. All patients underwent thyroid ultrasonography, and the data were analyzed by appropriate statistical methods.

RESULTS

The mean age of the study participants was 42.7 ± 17 years, and 14 of 50 patients (28%) had TPO antibody positivity. A goiter was present in 11 of 50 patients, and the thyroid volume by ultrasonography was similar between the 2 groups. Subclinical hypothyroidism was found in 14 of 50 patients (28%) but more frequently in the TPO antibody-positive group (8 of 14 or 57%) than in the TPO antibody-negative group (6 of 36 or 17%). The prevalence of AITD was 20 of 50 patients (40%) when the TPO antibody-positive group and those with subclinical hypothyroidism were considered collectively. None of the patients had overt hypothyroidism or hyperthyroidism. All other clinical, biochemical, and inflammatory variables did not differ significantly between the TPO antibody-positive and antibody-negative groups.

CONCLUSION

Our data showed a 40% prevalence of thyroid disease in patients with vitiligo in India. The risk is exacerbated in patients with thyroid autoimmunity; thus, regular screening of patients with vitiligo for AITD is needed.