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Updated: Jun 13, 2026
06:31
Precision Implementation of Minimal Erythema Dose (MED) Testing to Assess Individual Variation in Human Inflammatory Response
Published on: October 3, 2019
Erythema multiforme-like eruption localized to a sun-exposed area
Sevgi Akarsu1, Turna Ilknur, Emel Fetil
1Department of Dermatology, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey. sevgi.akarsu@deu.edu.tr
Photodermatology, Photoimmunology & Photomedicine
|April 27, 2010
Summary
A woman developed erythema multiforme-like skin lesions after sun exposure. This case highlights a rare variant of polymorphous light eruption, distinct from typical causes.
Area of Science:
- Dermatology
- Photodermatology
Background:
- Polymorphous light eruption (PMLE) is a common photosensitive disorder.
- Erythema multiforme (EM) is an acute, self-limited hypersensitivity reaction.
Observation:
- A 35-year-old woman presented with erythema multiforme-like cutaneous lesions in a photo-distributed pattern.
- The patient had no preceding history of infections or drug intake known to trigger EM.
- Standard phototesting showed normal tolerance, but photoprovocation was declined.
Findings:
- The patient was diagnosed with an erythema multiforme-like variant of polymorphous light eruption.
- This presentation mimics EM but is triggered by UV radiation exposure.
Implications:
- This case expands the spectrum of clinical presentations for polymorphous light eruption.
- It underscores the importance of considering photodermatoses in the differential diagnosis of EM-like lesions in sun-exposed areas.
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