What is the likely diagnosis for a 1-year-old girl with itchy, weepy, crusty, and cracky lesions on her face, scalp, trunk, and extensor surfaces?

Diagnosis: Infantile Eczema (Atopic Dermatitis)

This 1-year-old girl has infantile eczema (atopic dermatitis), which is the correct diagnosis based on her age-specific distribution pattern, characteristic lesion morphology, and pruritus. 1

Clinical Reasoning

The presentation is classic for infantile atopic dermatitis based on the following diagnostic criteria:

Age-Specific Distribution Pattern

• In infancy, atopic dermatitis characteristically starts on the cheeks and extends to the neck, trunk, and extensor surfaces of extremities 1
• This patient has lesions on face, scalp, trunk, and extensors—the exact distribution expected for her age group 1
• Notably, the diaper area is typically spared in infantile eczema, which helps distinguish it from other conditions 1

Characteristic Lesion Morphology

• The "crusty, cracky, and weepy" description indicates acute eczematous lesions with secondary bacterial infection 1
• Acute lesions present as erythema, exudation, papules, and vesiculopapules 1
• Crusting and weeping specifically suggest bacterial superinfection, commonly with Staphylococcus aureus 1

Diagnostic Criteria Met

The patient fulfills all three essential diagnostic criteria for atopic dermatitis 1:

1. Pruritus (described as "itchy") 1
2. Eczematous lesions with age-specific distribution (cheeks, face, scalp, trunk, extensors) 1
3. Chronic or relapsing course (>2 months duration required for infants) 1

Why Other Options Are Incorrect

Option B: Idiopathic Urticaria

• Urticaria presents as transient wheals that resolve within 24 hours, not persistent crusty/weepy lesions 2
• The chronic, fixed nature of these lesions excludes urticaria

Option C: Drug-Induced Allergy

• No medication history is provided 3
• Drug reactions typically present acutely after medication exposure, not with the chronic relapsing pattern described 4
• The age-specific distribution pattern is characteristic of atopic dermatitis, not drug reactions 1

Option D: Early Childhood Eczema

• This terminology is misleading—at 1 year of age, this is definitionally "infantile eczema" (infancy pattern) 1
• The transition to "childhood pattern" (affecting flexor surfaces) typically occurs after age 2-4 years 1
• The current extensor distribution confirms this is the infantile phase 1

Clinical Pitfalls to Avoid

The presence of crusting and weeping indicates likely secondary bacterial infection requiring treatment beyond standard eczema management 1. Bacteriological swabs should be obtained if the patient doesn't respond to initial treatment 1.

Other conditions to exclude in the differential diagnosis include 4:

• Scabies (look for burrows in finger webs) 1
• Immunodeficiency states (check for recurrent systemic infections, petechiae) 1
• Seborrheic dermatitis (typically less pruritic, different distribution) 4

The answer is A: Infantile Eczema.