Clinical presentation

Comedones are either open (blackheads: dilated pores with black plugs of melanin-containing keratin) or closed (whiteheads: small cream-coloured, dome-shaped papules). They appear at about the age of 12 years and evolve into inflammatory papules (Fig. 2), pustules or cysts (Fig. 3). The sites of predilection – the face, shoulders, back and upper chest – have many sebaceous glands. The severity of acne depends on its extent and the type of lesion, with cysts being the most destructive.

Fig. 2 Papular–pustular acne of the chin, with some whiteheads.

Fig. 3 Pustulocystic acne on the face.

Acne usually persists until the early twenties, although in a few patients, particularly women, the disease continues into the fifth decade. Scars may follow healing, especially of cysts or abscesses. Scars may be ‘ice-pick’, atrophic (Fig. 4) or keloidal.

Fig. 4 Scarring acne on the back.

Some variants of acne are seen:

Complications and differential diagnosis

Embarrassment, social withdrawal and depression are important sequelae of acne. These can improve with effective treatment. The rare and severe acne fulminans, seen in adolescent males, is associated with fever, arthritis and vasculitis. Long-term antibiotic treatment may induce a Gram-negative folliculitis.

Rosacea can usually be differentiated from acne (see below). Bacterial folliculitis is more acute than acne, but the two may coexist.

Management

Treatment depends on the type and extent of acne and the patient’s psychological state. ‘Over-the-counter’ creams have often already been used.

Local treatment is adequate for mild acne and is used with systemic drugs for more severe cases.

Oral treatment with antibiotics, retinoid or hormones is prescribed for moderate or severe acne, acné excoriée and in depressed patients.

Clinical presentation

Rosacea has an equal sex incidence. Although commonest in middle age, it also affects young adults and the elderly. The earliest symptom is flushing. Erythema, telangiectasia, papules, pustules (Fig. 5) and, occasionally, lymphoedema involve the cheeks, nose, forehead and chin. Rhinophyma, hyperplasia of the sebaceous glands and connective tissue of the nose (Fig. 5), and eye involvement by blepharitis and conjunctivitis are complications. Sunlight and topical steroids exacerbate the condition. Rosacea persists for years, but usually responds well to treatment. Rosacea lacks the comedones of acne and occurs in an older age group. Contact dermatitis, photosensitive eruptions, seborrhoeic dermatitis and lupus erythematosus often involve the face but are more acute or scaly, or lack pustules.

Fig. 5 Rosacea with rhinophyma in a woman. Rhinophyma usually affects men.

Management

Topically, metronidazole 0.75% cream (Rozex) or azelaic acid may be helpful. If this is ineffective, the usual oral treatment is oxytetracycline, initially 1 g daily, reducing to 250 mg daily after a few weeks and continued for 2–3 months. Erythromycin is an alternative. Repeated treatment is often needed. Isotretinoin can be used but is less effective than in acne. Plastic surgery is required for rhinophyma.