Metal allergy and systemic contact dermatitis: an overview

Area of Science:

• Dermatology
• Immunology
• Toxicology

Background:

• Contact dermatitis results from external skin exposure to allergens.
• Systemic contact dermatitis (SCD) occurs when systemic allergens concentrate in the skin via circulation.
• Metals like nickel, cobalt, chromium, and zinc are common environmental allergens causing various skin reactions.

Purpose of the Study:

• To explore the mechanisms and diagnostic methods for metal-induced systemic contact dermatitis.
• To evaluate the efficacy of in vitro diagnostic methods compared to traditional testing for metal allergies.

Main Methods:

• Review of existing literature on contact dermatitis and systemic reactions to metals.
• Discussion of diagnostic techniques including epicutaneous patch testing, oral metal challenges, and in vitro tests like lymphocyte stimulating test (LST).
• Highlighting the potential of cytokine production analysis from peripheral blood mononuclear cell cultures for diagnosing metal allergies and SCD.

Main Results:

• Metal allergies, particularly to nickel and cobalt, can manifest as allergic contact dermatitis and SCD.
• Dietary intake (e.g., nickel, cobalt) and dental materials (e.g., zinc) can trigger systemic reactions.
• In vitro methods, especially cytokine determination, show promise for discriminating metal allergies, including SCD, potentially surpassing LST.

Conclusions:

• Systemic contact dermatitis is a significant manifestation of metal allergy.
• Accurate diagnosis of metal sensitivity is crucial for managing allergic skin conditions.
• Novel in vitro diagnostic approaches offer improved accuracy in identifying metal-specific immune responses relevant to SCD.