Overview

Definition:
-Atopic dermatitis (AD), also known as atopic eczema, is a chronic, relapsing, inflammatory skin condition characterized by intense pruritus and eczematous lesions
-Proactive maintenance therapy aims to prevent flares and maintain skin barrier function between active disease exacerbations.
Epidemiology:
-It is the most common chronic inflammatory skin disease in childhood, affecting 15-20% of children globally
-Prevalence varies by region, with higher rates in developed countries
-There is a strong genetic predisposition, often associated with a personal or family history of asthma and allergic rhinitis (the atopic march).
Clinical Significance:
-AD significantly impacts a child's quality of life, leading to sleep disturbances, school absenteeism, and emotional distress for both the child and family
-Long-term management is crucial to prevent secondary infections, skin thickening (lichenification), and potential psychological sequelae
-Effective maintenance therapy is key to achieving long-term control.

Clinical Presentation

Symptoms:
-Intense pruritus, often worse at night
-Dry, sensitive skin
-Red, inflamed patches of skin
-Oozing or crusting of affected areas
-Skin thickening (lichenification) in chronic cases
-Areas affected vary with age: infants typically present with facial and extensor involvement
-older children show flexural pattern.
Signs:
-Erythema
-Edema
-Excoriations due to scratching
-Vesiculation in acute flares
-Lichenification in chronic lesions
-Scaling and dryness
-Secondary infection signs like pustules or honey-colored crusts.
Diagnostic Criteria:
-Diagnosis is primarily clinical, based on the Hanifin and Rajka criteria or the UK Working Party criteria
-Key components include: presence of pruritus, typical morphology and distribution, chronic or relapsing course, personal or family history of atopy
-Exclusion of other dermatoses is important.

Diagnostic Approach

History Taking: Detailed history of symptom onset, duration, triggers (food, environmental allergens, irritants, stress), previous treatments and response, presence of associated atopic conditions (asthma, allergic rhinitis), family history of atopy, and impact on quality of life.
Physical Examination:
-Systematic assessment of skin for characteristic lesions (erythema, dryness, excoriations, lichenification), distribution pattern according to age, and presence of secondary infection
-Assessment of overall skin barrier integrity.
Investigations:
-Generally not required for diagnosis in typical cases
-Allergy testing (skin prick tests, specific IgE) may be considered in select patients with suspected trigger foods or environmental allergens if immunotherapy is contemplated, but is not routine for diagnosis or management of AD itself
-Consider patch testing for contact dermatitis if suspicion arises.
Differential Diagnosis:
-Differential diagnoses include: seborrheic dermatitis, allergic contact dermatitis, irritant contact dermatitis, scabies, fungal infections, nymphomania, pityriasis rosea, psoriasis
-Features like itch severity, distribution, morphology, and response to therapy help differentiate.

Management

Initial Management:
-Identify and avoid triggers (irritants, allergens)
-Gentle skin care: lukewarm baths (short duration), mild non-soap cleansers, pat dry
-Vigorous application of emollients immediately after bathing is crucial for skin barrier repair.
Medical Management:
-Topical corticosteroids (TCS) are the cornerstone for flare treatment, with potency chosen based on age, location, and severity
-Low to medium potency TCS for face and intertriginous areas
-medium to high potency for trunk and limbs
-Topical calcineurin inhibitors (TCIs) like tacrolimus and pimecrolimus are alternatives for sensitive areas or long-term maintenance, especially when steroids are a concern
-Antihistamines (sedating at night for itch relief, non-sedating during the day)
-Antibiotics for secondary infections.
Proactive Maintenance Therapy:
-Application of emollients at least twice daily, even when skin appears clear, to maintain skin hydration and barrier function
-Regular, intermittent use of low-potency TCS or TCIs on previously affected areas 2-3 times per week to prevent relapse
-Education of parents on trigger avoidance and consistent application of topical therapies is vital
-Once-weekly applications of emollients with TCS or TCIs on historically problematic areas have also shown efficacy.
Supportive Care:
-Psychological support for child and family
-Education on disease, treatment adherence, and trigger avoidance
-Sleep hygiene measures
-Wet wrap therapy for severe flares
-Referral to specialists (allergist, dermatologist) if refractory or complex cases.

Complications

Early Complications:
-Secondary bacterial infections (Staphylococcus aureus is common, presenting as worsening eczema, pustules, honey-crusted lesions)
-Viral infections (eczema herpeticum, a disseminated herpes simplex infection, is a medical emergency)
-Fungal infections.
Late Complications:
-Lichenification and thickening of the skin
-Post-inflammatory hyperpigmentation or hypopigmentation
-Increased risk of asthma and allergic rhinitis (atopic march)
-Psychological issues like anxiety and depression.
Prevention Strategies:
-Strict adherence to proactive maintenance therapy with emollients and intermittent anti-inflammatory agents
-Prompt treatment of secondary infections
-Careful identification and avoidance of individual triggers
-Education on signs of infection for early intervention.

Prognosis

Factors Affecting Prognosis:
-Severity of disease at onset, presence of other atopic comorbidities, adherence to treatment, effectiveness of trigger avoidance, early and consistent management of flares and maintenance therapy
-Genetic factors can influence disease persistence.
Outcomes:
-Most children experience improvement or remission of AD by adolescence, but a significant proportion may have persistent disease or adult-onset AD
-Long-term proactive management can significantly improve quality of life and reduce disease severity.
Follow Up:
-Regular follow-up with a pediatrician or dermatologist is recommended, especially during childhood, to monitor disease activity, adjust treatment, reinforce education, and screen for associated atopic conditions
-Frequency depends on disease severity, typically every 3-12 months.

Key Points

Exam Focus:
-Proactive maintenance therapy is essential to prevent flares and improve quality of life
-Key components include consistent emollient use and intermittent anti-inflammatory application (TCS or TCIs)
-Recognize age-specific distribution patterns and common triggers
-Understand the management of secondary infections and eczema herpeticum.
Clinical Pearls:
-Emollients are not just moisturizers
-they are a critical part of skin barrier repair therapy
-Apply liberally and frequently, especially immediately after bathing
-Topical corticosteroids should be used at the lowest effective potency and duration, but fear of their use should not lead to undertreatment
-TCIs offer a steroid-sparing option for sensitive areas and maintenance
-Always consider secondary infections in recalcitrant or worsening AD.
Common Mistakes:
-Inconsistent emollient use
-Inadequate use of topical corticosteroids (too weak, too short duration) leading to flares
-Over-reliance on bathing without adequate moisturization
-Failure to identify and manage secondary infections promptly
-Neglecting the psychological impact on the child and family.