Lined with confused patients and concerned parents, the road of atopic eczema in infants is a seemingly complex one to navigate. Dr Paula Beattie MB BCh BaO, BSc, MD, Consultant Dermatologist and British Skin Foundation spokesperson, Royal Hospital for Children, Glasgow, advises on how you can help to demystify their treatment plan.
Atopic eczema is a multifactorial skin disease with both genetic and environmental factors influencing the structure and function of the skin barrier. An abnormal barrier allows water loss, leading to dryness, and leaves the skin vulnerable to irritants and allergens, as well as viruses and bacteria.
Natural moisturising factor, a compound in the skin that has the ability to absorb water from its surroundings, can be reduced in amount as a result of a genetic mutation and surfactants in wash products reduce that further.
Skin dryness often precedes clinically-obvious inflammation and is likely to represent subclinical inflammation. It’s one of the first signs of eczema and can be detected as early as day two of life in children who go on to develop eczema. (1) Scratching damages the barrier, leading to the release of cytokines which drive inflammation and itch.
Eczema affects 16-to-30 per cent of children in the UK (2), persisting into adulthood in around 40 per cent – particularly in those with early and widespread disease. Children with eczema are also more likely to develop other atopic disease, namely food allergy, asthma and allergic rhinitis. The mechanism of development of food allergy in infants with eczema is again an impaired skin barrier, so that food allergens are presented to the immune system via the skin for the first time, leading to sensitisation rather than the tolerance which occurs when presented via the gut. Skin barrier dysfunction at birth predicts food allergy at two years. (3)
Emollients in Action
Use of emollient improves skin hydration by replacing lipids and trapping water in the skin when used after bathing. Hence bathing can be encouraged so long as soap is avoided. Emollients also improve the function of the skin barrier and have been shown to help prevent irritant occupational eczema. Dryness is often associated with itching, and improved emollient use has been shown to reduce scratching and sleep disturbance, eczema severity, and flares of eczema; thereby reducing the need for topical corticosteroid (TCS). (4, 5)
Emollients should be used on all skin – not just areas of active eczema – and should be applied twice daily or more, continuing use between flares.
They should be prescribed in large quantities (250g-to-500g weekly) with additional pumps / tubs for childminder / nursery to encourage frequent use. Depending on skin dryness and acceptability, a cream and / or an ointment should be provided so that parents can decide which suits best. In general, ointments are better for dry skin and should be encouraged at night. Thick emollients are more effective as a barrier to chlorine in pool water and food in babies and infants being weaned. When prescribing or dispensing an emollient, advice should be given to apply it in a downward fashion along the direction of the hair.
The Emollient Effects
Emollients can be associated with adverse effects; thick emollients can occlude the hair follicles, resulting in inflammation, and application of any emollient to the skin in the opposite direction of hair growth can also irritate the hair follicles. Contamination of emollients in tubs with bacteria from the hands can occur but should not occur with pump dispensers and if the emollient is removed from the tub with a clean spoon to a clean surface. Creams and lotions contain preservatives and can sting when applied to broken or inflamed skin. Treating the inflammation with TCS will help reduce this.
Emollients such as aqeous cream and emulsifying ointment contain Sodium lauryl sulphate, a surfactant (soap) which can irritate and exacerbate dryness so they should never be used as a leave-on emollient and should probably also be avoided as a soap substitute.
It’s important to note that while emollients will improve the skin barrier, skin inflammation, which manifests clinically as redness, should be managed with TCS. TCS should be used according to NICE guidance with the use of a mild potency TCS to the face and a mild TCS, stepping up to a medium TCS, if not responding to areas of eczema on the body. In children over a year TCS potency can be increased to potent for the body and used in the same way.
Treatment should be for seven-to-14 days initially, and this should be repeated for flares. Treatment on two consecutive days each week to problem areas in those experiencing frequent flares (more than two each month) has been shown to reduce the frequency and duration of flares (www.nice.org.uk/guidance/cg57). TCS should be initiated at the first sign of skin inflammation from birth onwards. Gaining control of inflammation quickly will reduce the risk of skin infection and may improve disease outcomes long-term.
Unfortunately there is a paucity of evidence on whether it is more effective to apply emollients before or after TCS, but it’s likely that applying emollients first is more effective and the vast majority of recent publications – including NICE guidance – reflect that and advise a delay of approximately 30 minutes before TCS application. This is to allow absorption of the emollient and minimise dilution of the TCS by emollient.
Summary
In conclusion, when used in sufficient amounts alongside TCS for areas of inflammation, emollients help to reduce the symptoms and signs of atopic eczema, irritation by external environmental triggers, and the frequency of flares.
References
1. Kelleher M et al. Skin barrier dysfunction measured by transepidermal water loss at 2 days and 2 months predates and predicts atopic dermatitis at 1 year. J Allergy Clin Immunol. 2015; 135(4):930-5
2. Odhiambo et al . Global variations in prevalence of eczema symptoms in children from ISAAC Phase Three. J Allergy Clin Immunol. 2009 ;124(6):1251-8
3. Kelleher M et al. Skin barrier impairment at birth predicts food allergy at 2 years of age. J Allergy Clin Immunol. 2016; 137(4): 1111-1116
4. Mason JM et al. Improved emollient use reduces atopic eczema symptoms and is cost neutral in infants: before-and-after evaluation of a multifaceted educational support programme. BMC Dermatol. 2013:16:13:7
5. Wirén K, et al.Treatment with a barrier-strengthening moisturizing cream delays relapse of atopic dermatitis: a prospective and randomized controlled clinical trial.J Eur Acad Dermatol Venereol. 2009; 23(11):1267-72
