Napkin (diaper) dermatitis

Napkin dermatitis is the commonest type of napkin eruption. It is usually seen in infants who are only a few weeks old, and is rare after the age of 12 months. It is an irritant dermatitis due to the macerating effect of prolonged contact of the skin with faeces and urine. A glazed erythema is seen in the napkin area, sparing the skin folds. Erosions or ulceration may follow (Fig. 1), and hypopigmentation is a complication in pigmented skin. Secondary bacterial or Candida albicans infection is frequent, and the latter may account for the development of erythematous papules or pustules.

Fig. 1 Napkin dermatitis.

A severe erosive variant is seen here.

The differential diagnosis is from infantile seborrhoeic eczema and candidiasis, both of which tend to affect the flexures. The treatment of napkin dermatitis is aimed at keeping the area dry. The use of disposable super-absorbent nappies helps, as may more frequent changes. A bland white soft paraffin is used, with aqueous cream as a soap substitute, and a silicone-based cream (e.g. Drapolene) may have a protective action. Topical 1% hydrocortisone, with an antifungal (e.g. Daktacort or Canesten-HC), is also effective.

Infantile seborrhoeic eczema

Infantile seborrhoeic eczema starts in the first few weeks of life and tends to affect the body folds, including the axillae, groin and neck, but it also may involve the face and scalp. Flexural lesions present as moist, shiny, well-demarcated scaly erythema (Fig. 2), but a yellowish crust is often found on the scalp. The condition can usually be differentiated from napkin dermatitis (which spares the flexures), candidiasis (which is usually pustular) and atopic eczema (which is more pruritic, although differentiation can be difficult in some cases). Infantile seborrhoeic eczema is treated by emollients and 1% hydrocortisone ointment, or with a hydrocortisone–antifungal combination. Scalp lesions respond to 2% ketoconazole shampoo. Olive oil will help to soften the scalp scales of cradle cap.

Fig. 2 Infantile seborrhoeic eczema.

The condition involves the flexures.

Candidiasis

Infection with C. albicans is relatively common in the neonatal period. The organism can also secondarily complicate infantile seborrhoeic eczema or napkin dermatitis. Erythema, scaling and pustules are seen, often involving the flexures, and there may be satellite lesions. Treatment is with a topical anticandidal agent, e.g. 2% ketoconazole cream, and 2% miconazole gel orally.

Juvenile plantar dermatosis