The color of our hair and skin is determined by melanin. Currently, vitiligo is a disease of unknown cause, both medically and because of the lack of knowledge that the population has about this disease that directly affects the pigment of our skin. About 2% of the population suffers from vitiligo, and most of them go through a complicated adaptation process due to skin complexes or problems in social relationships with others. Even so, times are changing in this aspect and, thanks to the appearance of figures such as the model Winnie Harlow, they have helped this disease to be seen in a different way, to be accepted as something beautiful and different, and to continue normalizing its appearance.
World Vitiligo Day is celebrated on June 25, so we wanted to talk to our specialists to find out more about the disease and what advances are known about it.
Vitiligo affects the pigmentation of the skin.
Dr. Mariana Hoffner Zuchelli, Dermatology specialist on the Dermavit Salud team and head of the Medical Phototherapy Unit, explains that vitiligo is “a dermatological disease of autoimmune origin that mainly affects skin coloration. Thus, antibodies attack the melanocytes, the cells responsible for producing skin pigment, and this pigment is gradually lost”.
In fact, “vitiligo is one of the most frequent causes of depigmentation in the world”, as Dr. Josep González Castro, specialist in dermatology and director of IDERMA (Institute of Advanced Dermatology), explains. Dr. Gonzalez further explains that there are 3 clinical variants proposed by the Vitiligo Global Issues Consensus Conference between 2011 and 2012, according to its extension and distribution: vitiligo or non-segmental, characterized by symmetrical irregular white areas that can extend to any part of the body, usually follows a course of recurrent and remitting disease and with several variants: acrofacial (in distal area of the fingers and around orifices, eyes, nose, ears, mouth and anus), mucosal (affecting the oral and/or genital mucosa), generalized or common, universal (with complete or almost complete depigmentation), mixed and rare forms; segmental vitiligo, defined by non-symmetrical lesions and onset at younger ages; and indeterminate vitiligo. Distinguishing between these two forms is of utmost importance because the therapeutic options and prognosis are very different.
Thus, the main and most obvious symptom is depigmentation. “Lighter-colored spots appear and usually affect the areas of the face, around the eyes, the mouth, and can also affect more distal areas such as the hands, around the nails, the wrists or can also affect the folds such as the armpit area, the navel or the groin, among other areas,” Dr. Hoffner tells us. Dr. Gonzalez Castro adds that “the lesions are of variable size but with well-defined borders, completely white, and there is no detachment of the skin (i.e. they are not scaly). If it affects the scalp, it can cause the hair to grow white. If it affects the mucous membranes, it usually occurs on the genitals”.
In relation to how this disease can affect people, Dr. Hoffner explains that, “esthetically, it can cause problems, especially when it comes to relating to others,” but today it is a disease that is becoming normalized in society. “Depigmentation tends to be more noticeable the darker the skin base, and the higher the phototype, the more noticeable the difference between the more pigmented areas and the less pigmented areas”. Dr. Gonzalez Castro agrees with Dr. Hoffner: “the psychological manifestations considerably affect the quality of life, being a disorder that can be psychologically devastated and stigmatized, especially in dark-skinned individuals”.
An autoimmune disease of unknown cause
Whenever a disease appears, we want to quickly find out what has caused it to appear, but we cannot always resolve that question.
In the case of vitiligo, it is still a disease of unknown cause. “Like many autoimmune diseases, the specific trigger is not known; sometimes it’s a combination of genetic predisposition, some environmental factor, or an emotionally based precipitant,” says Dr. Hoffner. When it comes to autoimmune diseases, however, the causes are often unknown. “These are diseases where the body turns against itself by making antibodies, in this case, against melanocytes.”
There are several theories regarding the causes of vitiligo, Dr. Gonzalez Castro explains:
- One suggests that the body manufactures antibodies against the melanocyte (melanin-producing cell). Antimelanocyte-specific cytotoxic T-cells play a central role in the final effector stage. Genetic research revealed a multigenetic inheritance showing an overlap with other autoimmune disorders. However, some specific melanocyte genes were also affected.
- Another approach relates the disease to an inflammatory reaction that increases the number of free radicals that destroy melanocytes through an oxidative response.
- The newest theory suggests the existence of a defect in a protein (E-cadherin), which leads to an alteration in the adhesion mechanisms between the melanocyte and neighboring keratinocytes, causing the melanocyte to detach. This defect has become evident in vitiligo patients with a deficiency of this protein. Furthermore, this theory adds that the trigger of the pathology could be trauma or traumas (such as too tight clothing), which would affect the functioning of the protein.
The specialist also tells us that vitiligo can sometimes be accompanied by other associated autoimmune diseases, especially those affecting the thyroid. “The most common are thyroid disorders, so when we diagnose a case of vitiligo, we usually ask for a thyroid profile to rule out or confirm this association,” says Dr. Hoffner.
Phototherapy, the treatment that helps repigmentation
Currently, there are some treatments that help both to repigment and to stop or slow down depigmentation. Dr. Hoffner Gonzalez Castro explains that “there is no definitive cure for vitiligo, there are treatments or interventions for this disease, but the proper characterization of the type of vitiligo, consideration of the extent, duration of the disease and the efficacy of previous therapies can guide the management and maximize the effectiveness of the treatment”.
In addition, the treatments applied to patients are usually comprehensive, that is, they involve different modalities to treat the disease. On the one hand, we find oral treatments, “corticosteroids in phases where the disease is progressing rapidly, or some nutritional supplement or antioxidants that help to repigment”, topical treatments, “topical corticosteroids or immunomodulators and other types of topical applicators that help to protect the skin from the sun”. Physically, there are also treatments such as phototherapy, a treatment that has been performed for many years but is still in use today.
Dr. Hoffner explains that phototherapy is “a treatment with an efficacy of around 60% of repigmentation. It consists of 2-3 weekly sessions until 30 sessions in total, to see if the treatment works. In case of a good evolution and a good response from the patient, the treatment is continued”. This good response can be seen by checking how the lesions repigment from the edges and around the hair follicles until the spots are covered.
In fact, Dr. Gonzalez Castro adds that “narrow band UVB phototherapy can be used in patients who do not respond to topical treatment or in patients with extensive disease”. And, on the other hand, pigment cell transplantation offers an alternative to treat segmental vitiligo or stable non-segmental lesions.
Finding a cure as a challenge for the specialty
From a dermatological point of view, the specialists agree that it is necessary to continue research into other types of treatments in which progress is already being made. According to Dr. Hoffner, one of the most innovative treatments in the United States is that using JAK-kinase inhibito
rs, which have been studied for the treatment of rheumatoid arthritis, psoriasis and psoriatic arthritis. In one study, alopecia areata, a skin disease that shares pathophysiology with vitiligo, was successfully reversed. It is therefore a branch that continues to be investigated today with clinical studies.
From that perspective, the doctor stresses that the most important challenge right now is to continue searching for a cure for this disease. “We don’t have a magic wand to be able to eradicate it so that the patient can be cured. Therefore, we must continue to do research to be able to see how this disease can be better tackled and find a cure,” says the specialist.