Napkin_Rashes_Flashcards
What is the most common cause of a napkin (‘nappy’) rash?
Irritant dermatitis, due to the irritant effect of urinary ammonia and faeces. Creases are characteristically spared.
What are the characteristics of candida dermatitis in a napkin rash?
Typically an erythematous rash which involves the flexures and has characteristic satellite lesions.
What are the characteristics of seborrhoeic dermatitis in a napkin rash?
Erythematous rash with flakes. May be coexistent scalp rash.
What are the characteristics of psoriasis in a napkin rash?
A less common cause characterised by an erythematous scaly rash also present elsewhere on the skin.
What are the characteristics of atopic eczema in a napkin rash?
Other areas of the skin will also be affected.
What are the general management points for a napkin rash?
Disposable nappies are preferable to towel nappies, expose napkin area to air when possible, apply barrier cream (e.g. Zinc and castor oil), mild steroid cream (e.g. 1% hydrocortisone) in severe cases.
What is the management of suspected candidal napkin rash?
Management is with a topical imidazole. Cease the use of a barrier cream until the candida has settled.
summarise napkin rashes
Napkin rashes
Causes of a napkin (‘nappy’) rash include the following:
Type Notes
Irritant dermatitis The most common cause, due to irritant effect of urinary ammonia and faeces
Creases are characteristically spared
Candida dermatitis Typically an erythematous rash which involve the flexures and has characteristic satellite lesions
Seborrhoeic dermatitis Erythematous rash with flakes. May be coexistent scalp rash
Psoriasis A less common cause characterised by an erythematous scaly rash also present elsewhere on the skin
Atopic eczema Other areas of the skin will also be affected
General management points
disposable nappies are preferable to towel nappies
expose napkin area to air when possible
apply barrier cream (e.g. Zinc and castor oil)
mild steroid cream (e.g. 1% hydrocortisone) in severe cases
management of suspected candidal nappy rash is with a topical imidazole. Cease the use of a barrier cream until the candida has settled
A mother brings her 8-month-old infant to the GP due to the development of a nappy rash. On examination an erythematous rash with flexural sparing is seen. What is the most likely cause?
Irritant dermatitis
Psoriasis
Seborrhoeic dermatitis
Candida infection
Atopic eczema
The correct answer is Irritant dermatitis. This condition, also known as nappy rash or diaper dermatitis, is the most common cause of nappy rash in infants. It is caused by prolonged exposure to urine and faeces that irritates the skin, leading to an erythematous rash in the nappy area with flexural sparing (as these areas are less likely to be in contact with irritants). The rash often appears abruptly and can vary from mild (with only slight redness) to severe (with bright red, shiny inflammation).
Psoriasis is an unlikely diagnosis in this case. While it can occur at any age, onset before age 1 is extremely rare. Psoriasis tends to be well-demarcated, scaly plaques typically affecting extensor surfaces such as the elbows and knees rather than the nappy area.
Seborrhoeic dermatitis typically affects areas rich in sebaceous glands such as the scalp (‘cradle cap’), face and upper trunk. In infants, it may involve the groin but usually alongside the involvement of other sebum-rich areas.
An Candida infection could potentially cause a similar rash but there would typically be satellite lesions - small red spots away from the main area of redness - which have not been described here.
Atopic eczema, another common condition in infancy, usually starts on the face or body before spreading to other areas including flexures (opposite pattern compared to irritant dermatitis), and does not specifically affect the nappy area. Eczema often has a chronic relapsing course and may be associated with a personal or family history of atopy (asthma, hay fever or eczema).
