Related Experiment Video
Updated: May 20, 2026
08:02
A Mouse Ear Model for Allergic Contact Dermatitis Evaluation
Published on: March 24, 2023
Nummular eczema and contact allergy: a retrospective study
Domenico Bonamonte1, Caterina Foti, Michelangelo Vestita
1Department of Internal Medicine and Clinical Oncology-Section of Dermatology, University of Bari Medical School, Bari, Italy. d.bonamonte@dermatologia.uniba.it
Dermatitis : Contact, Atopic, Occupational, Drug
|July 26, 2012
Summary
Contact allergy is common in nummular eczema, affecting over 30% of patients. Patch testing is recommended for persistent cases to identify allergens like nickel sulfate.
Area of Science:
- Dermatology
- Allergology
Background:
- The causes of nummular eczema are not fully understood.
- Contact allergy's role in nummular eczema requires further investigation.
Purpose of the Study:
- To investigate the significance of contact allergy in the development of nummular eczema.
Main Methods:
- Retrospective analysis of 1022 patients diagnosed with nummular eczema.
- Patch testing performed on patients with various eczematous dermatitis.
- Clinical data and histopathology of lesions collected.
Main Results:
- Peak onset in the third decade; limbs are the most affected areas.
- 32.5% of patients exhibited positive reactions to allergens.
- Nickel sulfate, potassium dichromate, and cobalt chloride were the most common sensitizers.
Conclusions:
- Contact allergy is a frequent comorbidity in nummular eczema.
- Patch testing is highly recommended for all patients with persistent nummular dermatitis.
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