2. A 10-year-old girl has had patches of dry skin appearing and disappearing on her arms, legs, and neck for years. Recently manifested on her extensor forearm is an annular, distinctly salmon-pink plaque with a tenacious white scale. Scaly areas are observed in both postauricular sulci; several tiny pits are seen on her fingernails.
Diagnosis: It would be difficult to imagine a more clear-cut case of psoriasis, not only manifesting with a classic plaque on the extensor forearm but also with corroboratory stigmata behind the ears and classic fingernail pits.
It’s helpful to know that psoriasis affects almost 3% of the white population in the United States, meaning that you will see it with considerable frequency. It would also help if you knew the diagnosis can be corroborated by identification of other, lesser known features.
For more information, see “Girl, 10, Asks Tough Questions About Skin Problem.” Clin Rev. 2015;25(8):W2.