Medicine Journal 2015; 2(2): 19-23 Published online March 10, 2015 (http://www.openscienceonline.com/journal/med) The Relationship Between Melasma and Disturbances in the Serum Level of Thyroid Hormones and Indices Rezvan Talaee 1 , Iman Ghafarpasand 1 , Hamidreza Masror 2 1 Kashan University of Medical Science, Faculty of Medicine Department of Dermatology, Dermatology Lab, Beheshti Hospital, Kashan, Iran 2 McGill University, Faculty of Medicine, Department of Experimental Surgery, Jewish General Hospital, Montreal, Canada Email address R_talaee2007@yahoo.com (R. Talaee), h.masrour@gmail.com (H. Masror) To cite this article Rezvan Talaee, Iman Ghafarpasand, Hamidreza Masror. The Relationship Between Melasma and Disturbances in the Serum Level of Thyroid Hormones and Indices. Medicine Journal. Vol. 2, No. 2, 2015, pp. 19-23. Abstract Introduction: Melasma is a relatively common skin disorder that primarily affects areas exposed to sunlight. The cause of melasma is not well understood yet. Few studies have been performed on the relationship of melasma and thyroid disorders. In this study, we have investigated the association between melasma and thyroid parameters. Material and Method: In this study, 102 patients with melasma, referred to dermatology clinic of Kashan Shahid Beheshti hospital, were enrolled and compared with 55 healthy controls. Patients with melasma were divided into two groups: melasma with a known cause and idiopathic melasma. Patient information such as age, sex, duration of disease, menstrual status, underlying disease, cause of melasma and its severity (MASI score) were recorded in a questionnaire. T3, T4, TSH, Anti TPO and Anti Thyroglobulin were measured in all participants using the Immuno-chemiluminescence method. The data was then analyzed using SPSS version 16. Results: Mean serum levels of T3 and T4 were similar in all three groups. The mean serum level of TSH, Anti TPO and Thyroglobulin antibodies in patients with melasma were higher than the control group, but there was no statistically significant difference. The frequency of abnormal TSH levels in patients with idiopathic melasma was significantly higher than the other two groups (p=0.012). Conclusion: In this study, it was found that abnormal levels of TSH are associated with a higher risk of developing melasma. Also, it was found that serum levels of TSH, anti TPO and anti-thyroglobulin are higher in patients with melasma. Keywords Melasma, Thyroid Gland, TSH, Anti TPO, Anti-Thyroglobulin 1. Introduction Melasma (Chloasma) is a commonly acquired skin disease. It is a hypermelanosis that is primarily found on areas of skin with high sun exposure, such as the face. It is more common in women. Causes are multi-factorial and not ascertained. The different factors that can cause it include: oral contraceptives, genetics, U.V. exposure, ethnicity, cosmetics or it can be caused idiopathically (1, 2, 3). It is often seen on the forehead, upper lip, cheeks and chin. It has three dominant forms: centro-facial, mandibular and malar. It also has many risk factors such as systemic diseases and thyroid dysfunctions. The relationship between thyroid dysfunctions and skin signs is complex and there are few studies about it (4, 5, 6). Both hyper and hypo-thyroidism can be associated with melasma. Each of them can cause specific and unspecific rashes. Based on one study, thyroid dysfunctions are associated with dry skin 56% of the time, telogen effluvium 37.5% of the time, hair loss 40.62% of the time, melasma 18.7% of the time, and vitiligo, alopecia areata, xanthelasma palpebrarum 22% of the time, as well as pemphigus rarely (7). In some studies, a relationship between autoimmune thyroid disease and melasma has been shown. They measured anti-thyroglobulin antibodies and anti-microsomal antibodies and found that thyroid disorders are 4 times more likely in patients who have melasma, as opposed to the control group (4). Another study showed a relationship between melasma and Carney Complex (neoplastic syndrome involving the pituitary, thyroid, and testicles) (6). In many studies systemic disorders are believed to be involved with the appearance of melasma, but few studies have analyzed thyroid indices in melasma patients (3). Due to a dearth of studies and evidence, we decided to do