What is the difference between psoriasis and seborrheic dermatitis?

Psoriasis is characterized by the presence of distinct, silvery scales that develop on the skin due to an accelerated skin cell turnover process, leading to thickened patches known as plaques. These plaques can be itchy and may crack and bleed. In contrast, seborrheic dermatitis presents as greasy, yellowish flakes or crusts, often occurring in areas rich in sebaceous (oil) glands, such as the scalp, face, and upper back. This condition is generally less severe than psoriasis and may be associated with the overgrowth of yeast rather than a primary immune response.

Understanding these key differences in appearance is essential for accurate diagnosis and treatment, as they can significantly influence the management of each condition. While other options may touch on aspects of psoriasis and seborrheic dermatitis, they do not accurately reflect the critical differences in their clinical presentation.