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Paediatric Dermatology:Atopic dermatitis
Dr Danielle GreenblattConsultant Dermatologist
Royal Free Hospital
Scope of the Problem
• Common; burden on patient QOL and healthcare resources
• Systematic review – 69 cross-sectional and cohort studies– AD worldwide phenomenon– lifetime prevalence > 20%– Increasing prevalence low income countries, Africa and
East Asia– Deckers IA et al. PLoS ONE 2012
Epidemiology• urban–rural gradient of disease• broad-spectrum antibiotic exposure• traffic-related air pollution • obesity
• UV light• maternal contact with farm animals during pregnancy;
consumption of unprocessed milk• helminth infection during pregnancy• dog exposure in early life
• No consistent evidence that prolonged exclusive breastfeeding, routine childhood vaccinations and other viral/bacterial pathogens influence AD risk. Flohr. Allergy 2014
Pathogenesis
• Skin barrier defect- Filaggrin mutation
• Altered immunological pathways
Impact of Atopic Dermatitis
• Significant impact on health related QOL scores: – Sleep disturbance– Negative impact on schooling
• The effect comparable to other chronic disease of childhood such as diabetes and asthma– Lewis-Jones S. Quality of life and childhood atopic dermatitis: the misery of living
with childhood eczema. Int J Clin Pract 2006
• Altered family dynamics• loss of employment,• time-consuming treatment, and financial costs
• Emerson et Br J Dermatol 1998– Survey of 1760 children– Aged 1-5 years– AD– 96% attended GP in previous 12 months– 6% had been seen within secondary care
Clinical features
Guidelines
Management
Dietary interventions
• Maternal diet– No evidence that maternal Ag avoidance during
pregnancy can affect infant’s risk of eczema
– ? Ag avoidance diet to a high risk woman during lactation
– ? Ag avoidance by lactating mothers of infants with AD
• Kramer et al. Maternal dietary antigen avoidance during pregnancy lactation, or both, for preventing or treating atopic disease in the child. Cochrane Database Syst Rev. 2012
Dietary interventions
• Food allergies in child
IgE mediated Non-IgE mediated
Tests can be helpful Tests often not helpful
Food sensitisation 50% amongst infants with severe and early onset eczema (<3/12) - Hill D. Clin Exp Allergy 2007
Dietary interventions
• Risk assessment of child
• Consider GI symptoms
• Food diaries
• Consider risks of withdrawal of food from diet – nutritional
Other Allergens
• Inhalant allergens– Seasonal flares of eczema– Associated asthma and rhinitis– Facial eczema > 3 years
• Allergic contact dermatitis– Exacerbation of eczema previously controlled– If reaction to topical steroids
Infections
• 90% of patients with AD show colonisation with Staph aureus
• Cochrane review: little benefit of topical or oral antimicrobial therapy outside context of clinically infected eczema
Control of bacterial colonisation
Topical antiseptics
• Dermol 500• Octenisan• Bleach baths
Topical antibiotics
• Fucidin• Nasal
mupirocin
Systemic antibiotics
• If clinically impetiginised
• Significant reduction in Eczema Area and Severity (EASI) Index• Well tolerated
Topical treatment
• Emollients– Essential for all severities of eczema– provide skin with exogenous lipids; reduce TEWL– NICE guidance: children should be prescribed
250-500g/week
– Creamy – Rich cream – Greasy – Very Greasy
Bath emollients
• NHS spends > £16million on bath emollients (average cost of £6.29 per item)
• This is 38% of total cost of treatments prescribed for preschool children with eczema (matches spend on emollients directly applied to skin)
• BMJ Drugs and Therapeutics Bulletin 2007
Topical steroids
• Until recently little known about optimum usage
• Traditionally twice a day preparations
• 10 RCTs – no convincing evidence that 2x/day better than 1x (Williams et al)
• Once a day preparations such as mometasone furoate, fluticasone proprionate
• Potency tailored to the severity of eczema (NICE)
Topical steroids
• Dermovate • Nerisone ForteUltrapotent
• Betnovate• Elocon• Synalar• Fucibet
Potent
• Eumovate• Betnovate RD• Synalar 1:4
Moderately potent
• 1% Hydrocortisone• 0.5% Hydrocortisone
Mildly potent
Tang et al JACI 2014Systematic review 26 trials • Induction of remission
• Maintenance therapy• Weekend treatment
Adherence
Steroid phobia
• Common barrier to effective treatment in AD
• Caregivers concerned about TCs treat suboptimally– Insufficient quantities– Reduced frequency– “the creams don’t work”
• Education regarding appropriate strength, quantity, duration– Perceived risks of skin thinning– Concern that analagous to anabolic/oral steroids
Calcineurin inhibitors
• Tacrolimus and pimecrolimus• Approved in 2000-1• NICE advise “second line for moderate to severe eczema”• In practice: delicate areas
• FDA Black box warning in 2006– Theoretical concerns based on mouse model work– AAD taskforce concluded no causal evidence of link with
malignancy/immunosuppression unlikely
• Advise against long term use• Recommend photoprotection
When to refer• Uncertain diagnosis
• Management ineffective
• Non-responsive facial eczema
• Child/parent may benefit from advice
• Suspect an allergic contact dermatitis
• Significant psychosocial concerns
• AD with severe/recurrent infection
Secondary care
• Education– treatments– recognising infection– Step-up step-down therapy
• Written treatment plans• Access to nursing, dietician, allergists• Tailored management +/- occlusive therapy, phototherapy,
systemic agents, clinical trials
Questions?