Table 3 Atopic dermatitis and differential diagnosis. Modified from Ref. [1]
Disease | Age | Morphology | Distribution | Symptoms |
|---|---|---|---|---|
AD | Childhood | Erythematous eczematous weepy plaque with fine dry scale | Face, scalp, Extensor surfaces in infants, flexural surfaces in children, trunk, nails | Severe pruritus |
Seborrheic dermatitis | Any age | Salmon-pink fine papules coalescing into poorly defined plaques with variable greasy scaling. | Face, scalp, Retroauricular folds, neck, axillae, inguinal folds | Absent to mild-moderate pruritus |
Psoriasis | Any age | Well-demarcated, pink plaques with adherent silvery scale, confluent bright red plaque with sharply defined borders and relative lack of scale. | Extensor surface of joints (elbows, knees) and extremities, Retroauricular folds, axillae, umbilicus, diaper area, inguinal folds, genitalia, gluteal cleft, nails | Mild-moderate pruritus |
Allergic contact dermatitis | Any age, incidence increases with age | Geometric erythematous eczematous weepy plaques | Based on exposure | Severe pruritus |
Scabies | Any age | Poorly defined erythematous papules, nodules, burrows, pustules, and vesicles | Wrists, interdigital spaces, axillae, umbilicus, nipples, diaper area, | Severe nocturnal pruritus |
Mycosis fungoides | Adulthood, Hypopigmented MF More common in children | erythematous patches, papules, or plaques with subtle scale; polycyclic or annular, hypopigmented patches, often with fine scaling | Buttock, lower trunk, thighs, breasts, and groin | Pruritus |
Dermatomyositis | Childhood and middle age | Violaceous scaly papules, Periorbital violaceous edema | Small joints of hands and elbows, face | Myositis |
Immunodeficiency and metabolic disorders | Infancy | Eczema or eczema-like eruption, erythroderma | Spread, resistant to treatment | Other cutaneous and extracutaenous manifestations Blood testing and genetic investigations upon diagnostic hypothesis |