About Psoriasis FAQs Click on any topic to jump down the page. Psoriasis can be limited to a few plaques or can involve moderate to extensive areas of skin. For most people, psoriasis tends to be mild. In psoriasis, the immune system is somehow triggered, which in turn speeds up the growth cycle of skin cells. A normal skin cell matures in 28 to 30 days and is shed from the skin's surface unnoticed.
Psoriasis appears to be slightly more prevalent in women than men.
The average age of diagnosis is 28, and psoriasis most commonly appears between the ages of 15 and 35. Psoriasis in infants is considered rare, although betweeen 10 percent and 15 percent of those with psoriasis get it before age 10. About 150,000 to 260,000 new cases of psoriasis are diagnosed each year. No special blood test or other diagnostic tool exists for psoriasis. The diagnosis is usually determined through examination of the skin by a physician or other health care provider.