Which skin disorder is commonly associated with Addison's disease?

Vitiligo is the correct answer because it is an autoimmune condition that results in the loss of skin pigmentation due to the destruction of melanocytes, the cells responsible for producing melanin. Addison's disease, a disorder of the adrenal glands leading to insufficient production of cortisol and sometimes aldosterone, is also an autoimmune disorder in many cases. Patients with Addison's disease often have other autoimmune conditions, making them more susceptible to developing vitiligo. The association lies in the shared underlying autoimmune etiology, which increases the risk for both conditions.

On the other hand, psoriasis is primarily a chronic inflammatory skin disease and isn't directly associated with Addison's disease. Eczema, a term used for several types of skin inflammation, does not have a specific link to Addison's disease either. Alopecia areata, while it is another autoimmune condition that causes hair loss, is less commonly connected to Addison's compared to vitiligo. This makes vitiligo the most commonly associated skin disorder with Addison's disease.