Introduction

Among the causative factors of napkin dermatitis the roles of faeces, urine, friction, hydration, temperature, chemical irritants and the napkin itself have to be considered. The interaction between the different factors and the influence of the causative factors on the clinical features will be described. Napkin dermatitis does not occur in countries or settings where conventional napkins are not used [1]. In the 1990s, the frequency and severity of napkin dermatitis significantly decreased in westernized countries compared with previous rates. Above all, the most severe forms are now infrequently observed. Variants of napkin dermatitis characterized by severe erythema, large pustules and ulcers have become rare.

Napkins (Nappies, Diapers)

The role played by napkins is supported by all causative considerations. The decreased frequency and severity of napkin dermatitis in developed countries can be attributed to the improvement of napkin material. In this process, the introduction of disposable napkins and, more importantly, the new disposable napkins with their superabsorbent gel that is able to absorb 50 times its own weight of water, has been responsible for a significant improvement in hygienic care. Despite the term napkin dermatitis, napkins are not themselves able to cause the rash. In fact, allergic or irritant contact dermatitis caused by napkins is generally uncommon in children [2].

Modern disposable napkins mainly consist of an inner filtering layer, an intermediate layer able to absorb liquids, and an outer layer that is waterproof. The waterproof layer prevents perspiration and therefore increases the temperature and humidity of the environment. This layer plays a fundamental role in maintaining the impermeability of the napkin. From this point of view, the modern disposable napkin is much better than the traditional cotton napkin. The latter is characterized by significantly lower absorbency and thus is associated with higher humidity in the napkin area. In addition, cotton napkins must always be worn together with outer plastic waterproof pants. Compared with the traditional cotton napkins, modern disposable napkins reduce the contact time of the skin with urine. Tight elastic around the waist and legs of disposable napkins is useful, especially in nurseries and daycare centres, to prevent the spread of gastrointestinal infection. However, the increased occlusive effect of the napkins may be responsible for the rare cases of allergic contact dermatitis. The ideal napkin does not exist. The ideal napkin should be able to contain water without preventing air flow, and also inform the carer, possibly with a change in colour, as soon as the baby urinates.

Faeces

Prolonged contact with faeces is the most irritant toxic factor on the skin. Even babies who have never suffered from napkin dermatitis will develop napkin dermatitis when they have diarrhoea, especially that due to infections [3–5]. Diarrhoea results in prolonged contact of faeces with the skin and increases hydration of the skin. Napkin dermatitis improves immediately after diarrhoea stops. Many factors have been suggested to be responsible for the irritant capacity of faeces, ranging from acid stools burning the skin to alkaline stools [3,6]. Berg et al. [7] and Buckingham and Berg [8] suggested that faecal enzymes, such as proteases and lipases, could be responsible for the irritant potential of faeces. However, Yamamoto [9] was not able to show increased levels of proteases in children with napkin dermatitis. Kuwayama et al. [10,11] showed that faecal proteases and lipases play a minor role in the pathogenesis of napkin dermatitis. No significant relationship between faecal enzyme activity and severity of napkin dermatitis could be found. Moreover, lipase and protease activities were destroyed by heating faeces at 100°C for 5 min without a significant decrease in the irritation potential of the faeces. Kuwayama et al. concluded that other faecal factors are responsible for such toxic activities. The toxic substances are probably present in the fraction of substances of the water-soluble extract that exceed 5000 kDa. Other authors suggested that bile acids could play a role in the pathogenesis of napkin dermatitis [12]. The interaction between faeces and other factors is discussed below. However, the occurrence of napkin dermatitis around the normal, healthy anus shows that faeces alone can induce napkin dermatitis [13].

Urine

Urine may contribute to the pathogenesis of napkin dermatitis through skin hydration [10,14]. Urine and ammonia as single factors fail to induce erythema. The interaction of ammonia, bacteria, faeces, friction and other factors is described below [15]. However, urine, especially after incubation at 37°C (body temperature), may contain unidentified factors that could be responsible for irritation after prolonged exposure [16]. This was illustrated by the occurrence of napkin dermatitis around a normal, healthy urethral orifice after surgery of the urinary tract [13].

Friction

Related posts:

12 Collodion Baby 104 Disorders of Pigmentation 96 Knuckle Pads 140 Skin Gene and Cell Therapy 58 Bartonella Infections: Bacillary Angiomatosis, Cat Scratch Disease and Bartonellosis 168 Kawasaki Disease

Stay updated, free articles. Join our Telegram channel

Join