Nappy rash: everything you need to know.

Also known as nappy rash, diaper dermatitis is a skin inflammation located on the buttocks, thighs, and groin area.

This inconvenience primarily affects children, although it can also affect adults. Nappy rash can result from multiple factors, often associated with each other. One of the main causes is a humid environment, particularly when the skin is in prolonged contact with faeces or urine. This phenomenon is even more problematic in the case of diarrhoea, when the stools are particularly irritating. Humidity promotes skin maceration, making the epidermis more vulnerable to lesions. Urine, by altering the pH of the skin and producing ammonia, is particularly involved. Indeed, ammonia promotes the activity of faecal enzymes, such as proteases and lipases, which degrade the skin barrier and increase skin permeability, making it more fragile and prone to inflammation.

Friction, often associated with ill-fitting or overly tight nappies, also represents a major cause of nappy rash occurrence. Constant rubbing against the skin can compromise the integrity of the skin barrier, making the skin more prone to irritation. This is particularly true when a baby is heavily swaddled, thus creating an environment conducive to perspiration and moisture. In parallel, some disposable nappies, containing irritants for the sensitive skin of infants, can exacerbate the symptoms of nappy rash. Although all babies can be affected by nappy rash, girls seem to be more affected, probably due to greater exposure to nappy friction. This is at least what a study conducted by HOATH and his team on 31 infants suggests.

The nappy rash being primarily an inflammation, the first symptom to recognise it is a redness of the skin on the buttocks. This irritation can extend to the groin folds, thighs, and genital areas, zones particularly sensitive to friction and moisture. The affected area becomes more reactive and sensitive to touch and may appear slightly swollen, a sign of an ongoing inflammatory reaction.

Beyond redness, nappy rash causes irritation and itching, leading to a feeling of discomfort for the baby. The baby may become more restless, cry more, especially during nappy changes or baths, where contact with water and wipes can exacerbate the discomfort. In some cases, more pronounced red patches may form, sometimes accompanied by small blisters. These signs indicate a more advanced skin condition and require special attention to prevent a skin infection, particularly by yeasts of the type Candida albicans.

Even though nappy rash is generally mild in most cases, it requires attention. Primarily, it's important to keep the areas of the buttocks, groin, and thighs clean. To do this, regularly change nappies, as well as clothes that have been soiled by urine or faeces. Regularly clean the area with warm water, a gentle soap, and cotton or a clean microfibre towel. Avoid scented wet wipes, which could promote skin irritation. As much as possible, it is also advised to leave the infant's skin exposed to the air, in order to minimise friction as much as possible. Some natural treatments, such as chamomile or calendula extracts or sunflower oil, known for their anti-inflammatory and moisturising properties, can also alleviate nappy rash.

Finally, if that is not enough, ointments such as Oxyplastine or Eryplast, or corticosteroids can be used. However, caution is advised with the latter: they are used twice a day and their use should not be extended beyond two weeks. Indeed, corticosteroids are very effective in case of skin inflammation but, if used excessively, they can alter the skin barrier and cause atrophy of the epidermis, particularly on the sensitive skin of newborns.

• HOATH S. & al. Development of Diaper Rash in the Newborn. Pediatric Dermatology (2001).

• SCHEINFELD N. Diaper dermatitis: a review and brief survey of eruptions of the diaper area. American journal of clinical dermatology (2005).

• TIERNEY N. & al. Diaper Dermatitis: Etiology, Manifestations, Prevention, and Management. Pediatric Dermatology (2013).

• NIU G. & al. Safety evaluation for ingredients used in baby care products: Consideration of diaper rash. Regulatory Toxicology and Pharmacology (2017).

• HASANPOOR-AZGHADI S. B. & al. A Review Study of Diaper Rash Dermatitis Treatments. Journal of Client-Centered Nursing Care (2018).