Seborrheic dermatitis

Seborrheic dermatitis

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.

Seborrheic dermatitis

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)


Bazex syndrome (acrokeratosis paraneoplastica)

Bazex syndrome (acrokeratosis paraneoplastica)

Bazex syndrome denotes an acral psoriasiform dermatosis in association with internal malignancy. Elderly patients, usually males, present with a symmetric erythematous or violaceous, scaly eruption affecting the ears, nose, fingers, and toes. The knees and elbows may sometimes be involved. Vesicles and bullae are less common manifestations. In patients with black or darkbrown skin, the lesions can present with hyperpigmentation.

Palmoplantar lesions are keratodermatous and nail involvement ranges from paronychia, horizontal or vertical ridging, yellow discoloration and thickening to onycholysis and subungual keratotic debris.

Bazex syndrome (acrokeratosis paraneoplastica)

Patients with Bazex syndrome invariably have an associated systemic malignancy, most often affecting the oropharynx, larynx, esophagus, and lung, in descending order of frequency. Cervical lymph node metastases are commonly present. persistence of the cutaneous lesions is rare and they commonly regress following successful treatment of the underlying malignancy.

Source: P. McKee, J. Calonje – McKee’s Pathology of the Skin (Elsevier)