The coexistence of psoriasis and vitiligo: a review.

BACKGROUND: Psoriasis and vitiligo are both autoimmune diseases with an increased incidence noted in genetic relatives. They share similar trigger factors and have been observed to coexist in individuals. OBJECTIVE: The purpose was to review the literature on the coexistence of psoriasis and vitiligo and to determine if there is a higher than expected prevalence of psoriasis in patients with vitiligo and vice versa. METHODS: A literature review was conducted using Medline, EMBASE, and the Cochrane Library from 1968 to 2010. All articles that included reports of individuals with both psoriasis and vitiligo in the English language were documented. RESULTS: We identified 338 articles, among which 35 case reports and 7 case series were mentioned. For each case series, the prevalence of psoriasis in patients with vitiligo, or vice versa, falls within the prevalence range of the background population on which the study was based. CONCLUSION: An increase in the expected prevalence of psoriasis in individuals with vitiligo, or vice versa, was not found in our study, suggesting that the coexistence of the two diseases appears to be due to chance alone. Large epidemiologic studies are required to address with certainty whether psoriasis is more common in individuals with vitiligo and vice versa.