Relevance of autoimmune thyroiditis in children and adolescents with vitiligo

Background Vitiligo is the most common pigmentation‐related disorder worldwide. An autoimmune etiology is widely considered, and genetic factors may play an important role in its pathogenesis. The purpose of this study was to assess the incidence of thyroid dysfunctions and autoimmune thyroiditis in children with vitiligo and to identify related factors. Methods Fifty children with vitiligo and 50 control children were enrolled. Data on age, onset, duration, disease activity, presence of thyroid disorder, other autoimmune diseases, halo nevi, poliosis, and mucosal vitiligo were determined. Serum free triiodothyronine, free thyroxine, total T3, total T4, thyroid‐stimulating hormone, and antibodies to thyroperoxidase and thyroglobulin were measured. Thyroid gland efficiency was evaluated. Results The mean age at onset of vitiligo was 7.26 ± 4.43 years. The duration of vitiligo was 2.26 ± 2.95 years. Vulgaris‐type vitiligo was the most common form in our patients (56%), and 42% reported at least one family member with thyroid disorder, autoimmune disease, or both. Overt hypothyroidism or hyperthyroidism were not detected. We found a significant association between autoimmune thyroiditis and both sex and disease duration (P = 0.046 and P = 0.07, respectively), but no association between autoimmune thyroiditis and age, age at onset of vitiligo, halo nevi, poliosis, mucosal involvement, disease activity, or family history of vitiligo, autoimmunity, or thyroid disorders. Conclusions Children with vitiligo show an increased incidence of autoimmune thyroiditis. Children with vitiligo, especially girls and subjects with generalized/vulgaris‐type vitiligo, should be screened annually for thyroid function and antithyroid antibodies to assist in the early diagnosis and therapy of autoimmune thyroiditis.     

合并一种自身免疫性疾病的白癜风患者临床分析

白癜风为一种常见的局限或泛发性皮肤黏膜色素脱失性皮肤病。病因尚未明确,考虑可能与遗传、自身免疫、黑素细胞自身破坏等因素相关。通过大量临床实践发现,此病患者易合并其他自身免疫性疾病,如斑秃、银屑病、甲状腺疾病等。本文通过收集整理合并不同自身免疫性疾病的白癜风患者临床数据,进行回顾性分析比较,并做统计学分析,以探讨白癜风与其他自身免疫性疾病是否存在关联。     

An approach to the correlation between vitiligo and autoimmune thyroiditis in Chinese children

Background. Vitiligo is a common skin depigmenting disease, which is thought to have, at least partly, an autoimmune aetiology. Aim. To explore the correlation between paediatric vitiligo and other associated diseases, with an emphasis on autoimmune thyroiditis (AT). Methods. In total, 363 paediatric patients (198 boys, 165 girls) with vitiligo and 93 healthy children (55 boys, 38 girls) were screened for autoimmune thyroiditis. The two groups were matched for age and gender. Children with vitiligo were split into two groups according to type (segmental and nonsegmental vitiligo). Demographic data, clinical features and examinations were recorded using questionnaires. Thyroid function tests including free triiodothyronine, free thyroxine and thyroid‐stimulating hormone were performed. Anti‐thyroid peroxidase antibody) and anti‐thyroglobulin antibody levels were assessed as well. Other associated diseases were also monitored in this study. Results. Of the 363 patients, 43 (11.8%) had abnormal levels of studied thyroid parameters, compared with 4 of the 93 controls (4.3%); the difference was significant (P = 0.04). The alterations of thyroid parameters and the incidence of AT in patients with nonsegmental vitiligo were both significantly different (P < 0.05, P = 0.04) relative to the segmental vitiligo group. Of the 363 patients, 67 (18.5%) had other associated diseases. There were no differences in the rates of other associated diseases between patients with segmental vitiligo and those with nonsegmental vitiligo (P > 0.05). Conclusions. A significant incidence of thyroid dysfunction was found in paediatric patients with nonsegmental vitiligo. As vitiligo usually appears before the development of the thyroid disease, it may be advantageous to screen thyroid functions and antibody levels in all paediatric patients with vitiligo, especially those with nonsegmental vitiligo.     

Subcutaneous sarcoidosis associated with vitiligo, pernicious anaemia and autoimmune thyroiditis

We report a patient with pernicious anaemia, primary autoimmune hypothyroidism and vitiligo, who presented with subcutaneous nodules. Histopathology of the nodules revealed noncaseating granulomas, consistent with a diagnosis of sarcoidosis. Mild pulmonary sarcoid was also detected. Although an association between sarcoidosis and other autoimmune diseases is well-recognized, the presence of the particular autoimmune diseases in our patient and the involvement of subcutaneous fat in the sarcoidal inflammation, appears to represent a most unusual clinicopathological combination.     

儿童白癜风与甲状腺功能指标异常及其他免疫性疾病的关系

目的 探讨儿童白癜风与甲状腺功能指标异常及其他免疫性疾病的关系。方法 对363例白癜风儿童（男198例 ,女165例 ）和 93 例对照儿童（男55例,女38例）进行甲状腺功能指标的检查。结果 363例白癜风儿童中有43例（11.8%）儿童有不同程度的甲状腺功能指标的异常,93例对照组正常儿童中有4例儿童甲状腺功能指标异常,两者比较差异有统计学意义。白癜风儿童甲状腺功能指标异常发生率明显增高（P < 0.05）。而43例甲状腺功能异常的白癜风儿童中,寻常型白癜风儿童为39 例（13.6%）,节段型白癜风儿童为4 例（5.3 %）,寻常型比节段型白癜风儿童甲状腺功能指标异常发生率有明显增高（P < 0.05）。结论 儿童寻常型白癜风患者的甲状腺功能指标异常的发生率明显增高。     

The genetics of generalized vitiligo and associated autoimmune diseases

Generalized vitiligo is an acquired disorder in which patches of depigmented skin, overlying hair, and oral mucosa result from progressive autoimmune loss of melanocytes from the involved areas. Although vitiligo is perhaps the most common pigmentary disorder, insufficiently clear clinical definition of the disorder and lack of a good laboratory animal model have inhibited progress in understanding its pathobiology, its environmental triggers, and in developing specific and effective therapeutic approaches. Vitiligo results from a complex interaction of environmental, genetic, and immunologic factors, which ultimately contribute to melanocyte destruction, resulting in the characteristic depigmented lesions. In the past few years, studies of the genetic epidemiology of generalized vitiligo have led to the recognition that vitiligo is part of a broader, genetically-determined, autoimmune/autoinflammatory diathesis. Attempts to identify genes involved in vitiligo susceptibility have involved both allelic association studies of candidate genes and genome-wide linkage analyses to discover new genes, and these studies have begun to shed light on the mechanisms of vitiligo pathogenesis. It is anticipated that the discovery of biological pathways of vitiligo pathogenesis will provide novel therapeutic and prophylactic targets for future approaches to the treatment and prevention of vitiligo and its associated autoimmune diseases.     

The analysis of genetics and associated autoimmune diseases in Chinese vitiligo patients

Vitiligo is a common skin and hair depigmentary disorder that results from selective destruction of melanocytes. It occurs in a typical multifactorial, polygenic inheritance. Several studies have indicated that vitiligo is associated with some autoimmune diseases. In this paper we examined 6,516 vitiligo patients including clinical characteristics, familial involvement, and their association with other autoimmune diseases. Compared with sporadic vitiligo probands, familial vitiligo probands have earlier age onset and longer disease duration. The prevalences of four autoimmune diseases namely rheumatoid arthritis, chronic urticaria, alopecia areata and psoriasis, were significantly elevated in generalized vitiligo probands and their first-degree relatives. The prevalences of chronic urticaria, rheumatoid arthritis, psoriasis were much higher in familial generalized vitiligo probands. In addition, the prevalences of diabetes mellitus and asthma were also higher in familial vitiligo probands. These findings indicate that generalized vitiligo may share common genetic aetiologic links with other autoimmune diseases, and the genetic component of familial generalized vitiligo is stronger.     

Connective tissue panniculitis in a child with vitiligo and Hashimoto's thyroiditis

SUMMARY A 9-year-old girl presented with a 6-month history of inflamed tender nodules in the pretibial area. These eventually healed leaving depressed areas of atrophy and loss of subcutaneous tissue. Histology showed a predominantly lymphocytic lobular panniculitis, consistent with connective tissue panniculitis. Investigations revealed an elevated thyroid stimulating hormone, elevated thyroid antiperoxidase antibody and a weakly positive antinuclear antibody (titre 1 in 40). She was commenced on hydroxychloroquine 300 mg daily, which resulted in resolution of the panniculitis. She developed focal vitiligo on the thighs. This gradually improved with 0.1% mometasone furoate ointment. The hydroxychloroquine dose was tapered to 200 mg daily after 12 months, then to 100 mg daily after 18 months therapy. Her thyroid autoantibody levels continued to rise and the hydroxychloroquine was increased again to 300 mg daily. She became borderline hypothyroid. Hashimoto's thyroiditis was diagnosed. Thyroxine was instituted with a resultant improvement in her thyroid blood tests. The lipoatrophy has not developed further during 2-year follow up.     

Fatigue in systemic lupus erythematosus and other autoimmune skin diseases

People with the disease systemic lupus erythematosus (SLE) often suffer from fatigue, reducing quality of life and contributing to ill health. The authors of this study, based in Pennsylvania and New Jersey, USA, studied whether fatigue was a feature in other autoimmune skin conditions. Autoimmune means when the body's immune system, which usually fights off infection, actually targets healthy cells. They used a 36-item questionnaire (SF-36), with a specific vitality scale to measure levels of fatigue in controls (people without SLE) and patients with SLE, and the diseases chronic cutaneous LE, amyopathic dermatomyositis and autoimmune blistering conditions. Levels of fatigue were worst in the patients with SLE, but all the other conditions studied were linked with greater fatigue than the control group. The levels of fatigue were similar in the groups with dermatomyositis and blistering conditions, but less in the patients with cutaneous LE. The authors conclude that fatigue is an important feature of these autoimmune conditions, and is detrimental to quality of life.