Which statement is not correct regarding the etiology or incidence of psoriasis vulgaris?

Which statement is not correct regarding the etiology or incidence of psoriasis vulgaris?

• A. Occurs more commonly in dark-skinned ethnic individuals
• B. Associated with constant rubbing or trauma to exposed affected areas such as elbows
• C. Associated with overproduction of epithelial cells
• D. Associated with epithelial cells that migrate to the skin surface much more quickly than normal

Answer: (A)

Psoriasis vulgaris is driven by immune-mediated keratinocyte hyperproliferation, leading to markedly accelerated epidermal turnover and the formation of thick, scaly plaques. The rapid migration of keratinocytes to the skin surface explains the visible excess scale and plaque buildup. Trauma to skin can trigger new lesions in exposed areas through the Koebner phenomenon, so rubbing or scratching can worsen or initiate plaques on elbows and other sites. Regarding who gets it, psoriasis is more common in people of European descent and is not more prevalent in dark-skinned individuals; in fact, prevalence is lower in dark-skinned populations, and lesions may be less conspicuous or underrecognized. The combination of immune dysregulation, increased epithelial cell production, and faster epidermal turnover underpins both the pathophysiology and the clinical pattern of psoriasis.

Psoriasis vulgaris is driven by immune-mediated keratinocyte hyperproliferation, leading to markedly accelerated epidermal turnover and the formation of thick, scaly plaques. The rapid migration of keratinocytes to the skin surface explains the visible excess scale and plaque buildup. Trauma to skin can trigger new lesions in exposed areas through the Koebner phenomenon, so rubbing or scratching can worsen or initiate plaques on elbows and other sites. Regarding who gets it, psoriasis is more common in people of European descent and is not more prevalent in dark-skinned individuals; in fact, prevalence is lower in dark-skinned populations, and lesions may be less conspicuous or underrecognized. The combination of immune dysregulation, increased epithelial cell production, and faster epidermal turnover underpins both the pathophysiology and the clinical pattern of psoriasis.