Medical Terminology for Skin Allergies
The medical term for skin allergies depends on the specific type: "allergic contact dermatitis" (ACD) refers to immune-mediated reactions from direct skin contact with allergens, while "atopic dermatitis" (also called atopic eczema) describes the chronic inflammatory condition associated with systemic allergic tendencies. 1
Primary Medical Terms
Allergic Contact Dermatitis (ACD)
- ACD is a type IV delayed-type hypersensitivity reaction to environmental chemicals (haptens or prehaptens) that bind to epidermal carrier proteins, forming complete antigens that trigger sensitization and inflammatory reactions upon subsequent exposure 1
- This manifests as eczematous lesions that are often clinically indistinguishable from atopic dermatitis 1
- ACD affects 6-60% of patients with atopic dermatitis, making it at least as common in this population as in the general population 1
Atopic Dermatitis (Atopic Eczema)
- Atopic dermatitis is a chronic inflammatory skin disease characterized by intense itching and recurrent eczematous lesions, most often starting in infancy but highly prevalent in adults 2
- This condition involves defective epidermal barrier function, aberrant immune responses, and abnormal neural activation 3
- The term "eczema" and "dermatitis" are used synonymously to describe a polymorphic pattern of inflammation 1
Additional Specific Terms
Contact Dermatitis Subtypes
- Irritant contact dermatitis: Non-immune-mediated skin irritation from direct chemical damage, more common than allergic forms and accounting for approximately 80% of contact dermatitis cases 1, 4, 5
- Photoallergic/phototoxic contact dermatitis: Reactions triggered by light exposure to certain substances 1, 4
- Systemic contact dermatitis: Occurs after systemic administration of a substance to which topical sensitization previously occurred 1, 4
- Protein contact dermatitis: Results from repetitive handling of proteins such as vegetables, meats, fish, flour, and animal products 4
Clinical Context
Key Distinguishing Features
- The words "eczema" and "dermatitis" describe the same pattern: erythema and vesiculation in acute phases, dryness and lichenification in chronic phases 1, 4
- Contact dermatitis specifically describes reactions to external agents, whether acting as irritants or allergens 1, 4
- Clinical features alone are unreliable in distinguishing between allergic contact dermatitis, irritant dermatitis, and endogenous eczema, particularly with hand and facial presentations 4
Common Pitfall: The colloquial interchangeable use of "atopic dermatitis" and "eczema" creates confusion—eczema is a generalized descriptive term for a particular skin appearance common to multiple diagnoses, while atopic dermatitis is a specific disease entity 3