Vitiligo and alopecia areata are two fairly common skin conditions and are disfiguring for the people they suffer from.
However, their symptoms are very different.
Vitiligo manifests as white patches on the skin while alopecia areata is characterized by patchy hair loss.
In fact, until recently the clinical differences did not suggest a possible correlation between the two diseases.
Autoimmune diseases have been classified into medical sub-specialties and the types of tissue targeted by the defective immune response.
Although this is useful for clinical purposes, it often leads to an excessive simplification of the disease and the implementation of non-targeted treatments.
Over the past few decades, researchers have made significant progress in understanding the immune system.
This made it possible to move from categorization by target tissue to immune pathogenesis, thus allowing the development of targeted treatments.
What is Vitiligo?
Vitiligo is an autoimmune, depigmenting, acquired and chronic skin disease.
It is caused by the destruction of epidermal melanocytes.
Vitiligo is a condition that can affect children, in fact about a third of cases occurs before the age of 12 and half of cases before the age of 20.
This condition can be divided into two main forms: common and segmental vitiligo.
Common vitiligo is characterized by bilateral and symmetrical depigmented patches and can progress unpredictably.
In contrast, segmental vitiligo has a unilateral distribution, progresses rapidly over 6-12 months, and then stabilizes throughout the patient’s life.
Alopecia areata
Alopecia areata is an acquired form of non-scarring hair loss.
In most patients, the onset of the disease occurs before the age of 30 and is also a family and pediatric condition.
The severity of the disease ranges from small patches of alopecia to complete baldness and the loss of remaining body hair.
About 50% of patients experience spontaneous hair regrowth within a year, although most recur. The unpredictable course of the disease causes considerable psychological distress.
Vitiligo and alopecia areata correlation
Despite the clinical differences, vitiligo and alopecia areata share clinical commonalities.
Both, in fact, have an irregular distribution and are minimally symptomatic, unlike more inflammatory skin diseases such as psoriasis or atopic dermatitis.
Both are associated with other autoimmune conditions, notably thyroid autoimmunity, with an estimated prevalence of 19.4% with vitiligo and 28% with alopecia areata
Both conditions also appear to occur more commonly together than expected by chance, with a reported prevalence of 3 to 8% of vitiligo in patients with alopecia areata.
Exploring these similarities has allowed for a better understanding of their pathogenesis.
