Typical Appearance of Eczema
Eczema presents as an itchy inflammatory skin condition characterized by erythema, papules, vesicles, scaling, and crusting in acute stages, while chronic eczema shows lichenification and hyperpigmentation with accentuated skin markings. 1
Age-Specific Distribution Patterns
The location of eczema varies significantly by age:
- Infants and children under 4 years: Lesions typically affect the cheeks, forehead, scalp, and outer limbs 1, 2, 3
- Older children and adults: Eczema predominantly involves flexural areas including the folds of elbows (antecubital fossae), behind knees (popliteal fossae), around the neck, and head/neck regions 1, 3
- Important caveat: Rash in the diaper area of infants is rarely atopic dermatitis 3
Primary Morphological Features
Acute Eczema Appearance
The acute phase demonstrates polymorphism with multiple lesion types present simultaneously:
- Erythematous papules that arise from numerous tiny foci (multiple-pinpoint condition) 4
- Vesicles and seropapules with serous exudates 4, 3
- Weeping and crusting, particularly when bacterial superinfection is present 1
- Excoriations and crusted erosions from scratching 3
- Scales and pustules may also be present 4
Chronic Eczema Appearance
Long-standing disease produces distinct changes:
- Lichenification: Thickened skin with accentuated skin markings from chronic scratching 4, 3
- Hyperpigmentation from increased melanogenesis and dermal pigment deposition 4
- Possible hypopigmentation in some cases 4
- Dry, scaly plaques with erythema 3
Essential Diagnostic Criteria
To diagnose atopic eczema, the British Association of Dermatologists requires:
An itchy skin condition (or report of scratching/rubbing in a child) PLUS three or more of the following:
- History of itchiness in skin creases (elbows, neck) or cheeks in children under 4 years 1
- History of asthma or hay fever (or atopic disease in first-degree relative for children under 4 years) 1
- General dry skin in the past year 1
- Visible flexural eczema (or cheek/forehead involvement in young children) 1
- Onset in the first two years of life 1
Critical Red Flags in Appearance
Bacterial Superinfection
Look for these warning signs requiring immediate treatment:
- Extensive crusting (honey-colored) 1
- Weeping lesions with serous or purulent discharge 1
- These findings suggest Staphylococcus aureus infection requiring antibiotics 2, 5
Eczema Herpeticum (Medical Emergency)
This life-threatening complication has a distinctive appearance:
- Multiple uniform "punched-out" erosions that are very similar in shape and size 1, 5
- Grouped vesiculopustular eruptions 5, 3
- Less commonly, vesiculation in grouped patterns 1
- Requires immediate systemic acyclovir plus empirical antibiotics 2, 5
Characteristic Symptoms Beyond Appearance
- Intense pruritus is the hallmark symptom and drives the scratch-itch cycle 4, 6
- Xerosis (general dry skin) is universally present 6, 7
- The condition is chronic and relapsing with variable expressivity 6
Common Pitfalls to Avoid
When assessing eczema appearance, be aware that deterioration in previously stable disease may indicate: