Seborrheic dermatitis is a common dermatosis which affects up to 1–3% of the population. There is a male predominance. It presents in infants, with a second peak affecting adults. There is often a family history of the disease. It particularly affects those areas where sebaceous glands are most numerous, i.e., the scalp, forehead, eyebrows, eyelids, ears, cheeks, presternal and interscapular areas.
Occasionally, the flexural regions are affected (intertrigo). Often the lesions of seborrheic dermatitis are sharply marginated, dull red or yellowish, and covered by a greasy scale. 43 they are thereforeeasily confused with psoriasis.
Dandruff and cradle cap are also sometimes included within the spectrum of seborrheic dermatitis.
Seborrheic dermatitis is one of the most common dermatoses seen in patients with acquired immunodeficiency syndrome (aIDS). Seborrheic dermatitis has also been associated with stress and neurological disorders including parkinson’s disease, syringomyelia, and trigeminal nerve injury.
Source: P. McKee, J. Calonje – McKee’s Pathology of the Skin (Elsevier)