]> 2026-07-31T11:52:03+00:00 WBR0377 0 en Actinic keratosis Actinic keratosis (answer A) is a premalignant condition of thick, scaly, or crusty patches of skin. It is most common in fair-skinned people who are frequently exposed to the sun, because their pigment isn't very protective. It usually is accompanied by solar damage. Since some of these pre-cancers progress to squamous cell carcinoma, they should be treated. Seborrheic keratosis Seborrhoeic dermatitis Seborrhoeic dermatitis (answer C) is an inflammatory skin disorder affecting the scalp, face, and torso. Typically, seborrheic dermatitis presents with scaly, flaky, itchy, and red skin. It particularly affects the sebaceous-gland-rich areas of skin. In adolescents and adults, seborrhoeic dermatitis usually presents as scalp scaling similar to dandruff or as mild to marked erythema of the nasolabial fold Actinic cheilitis Actinic cheilitis (answer D) also known as solar cheilitis is the counterpart of actinic keratosis of the skin and can develop into squamous cell carcinoma. In actinic cheilitis, there is thickening whitish discoloration of the lip at the border of the lip and skin. There is also a loss of the usually sharp border between the red of the lip and the normal skin, known as the vermillion border. Pityriasis rosea Pityriasis rosea is a skin disease marked by patches of pink, oval rash of unknown etiology. Its appearance is very different from what’s shown here. Seborrheic keratosis resembles flattened or raised warts, but have no viral origins and may exhibit a variety of colors, from pink or yellow through brown and black. Because only the top layers of the epidermis are involved, seborrheic keratoses are often described as having a "stuck-on" appearance. Darkly pigmented lesions can be hard to distinguish from nodular melanomas. If in doubt, a skin biopsy should be performed.<br/> '''Educational Objective:''' <br/> '''References:''' Internal medicine Mahmoud Sakr M.D. B Dermatology 2020-10-28T00:22:43Z 2459150.5157755 WBR0377