The history of onset and characteristics of the patches are consistent with vitiligo. Furthermore, vitiligo is sometimes associated with a history of local trauma. This patient’s vitiligo would be considered an example of generalized or non-segmental vitiligo, as it affects his neck, leg and genital area.

Vitiligo is an acquired, idiopathic , chronic disorder of depigmentation . It is the most common cause of depigmentation worldwide and affects 0.5–1 % of the population [1, 2]. Vitiligo affects genders and races equally, and it can occur at any age. Epidemiological studies suggest the mean age of onset is 24 years, however there are mixed reports on age predominance [1, 2]. It is likely the majority of vitiligo cases present before the age of 20 years [1, 3, 4]. The exact cause of vitiligo is unknown; however, it is thought to involve multiple genetic and environmental factors. The current understanding of pathogenesis is that autoimmune-mediated processes lead to destruction of the skin’s pigment cells, the melanocytes.

Vitiligo has two distinct subtypes: generalized or non-segmental, and segmental vitiligo. Generalized vitiligo , which can involve widespread loss of pigment in patches that are often symmetrical, accounts for 85–90 % of vitiligo cases. It is associated with other autoimmune conditions, such as diabetes, rheumatoid arthritis, psoriasis, hypothyroidism and hyperthyroidism , and Addison’s disease , in 20–30 % of cases [1–4]. Generalized vitiligo shows polygenic inheritance patterns. There is a 23 % concordance rate in monozygotic twins [2]. Segmental vitiligo , which involves loss of pigment in smaller patches on one side of the body in a limited area, is thought to be a genetically distinct entity. Factors predisposing specific areas of the body to developing vitiligo include sun exposure, physical trauma, inflammation, and vitamin deficiency. Hormonal changes associated with pregnancy have also been implicated in the formation of patches [2].