Korean J Dermatol.
2021 Mar;59(3):206-211.
An Analysis of the Clinical and Photobiological Characteristics of Solar Urticaria: A 15-year Retrospective Study
- Affiliations
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- 1epartment of Dermatology, Konkuk University School of Medicine, Seoul, Korea
Abstract
- Background
Solar urticaria (SU) is a rare type of photodermatosis characterized by the appearance of itchy wheals and erythema within minutes after exposure to sunlight or artificial light. Only a few studies have analyzed the clinical and photobiological features of SU in Asia.
Objective
We aimed to analyze the clinical and photobiological characteristics of SU.
Methods
We retrospectively investigated the medical records of patients with SU who visited the Department of Dermatology at the Konkuk University Medical Center between January 2005 and October 2020.
Results
Of the 52 patients, 43 (82.7%) were men, and 9 (17.3%) were women. The mean age at onset was 17.5 years (5∼47 years), and the mean threshold time was 21.2 minutes. Among the 36 patients who underwent phototesting, the action spectrum predominantly responsible for SU was ultraviolet (UV) A only in 14 (38.9%) patients and visible light (415 nm) only in nine (25.0%) patients. Three patients (8.3%) were induced by both UVA and visible light (415 nm). In eight (22.2%) patients, the symptoms were triggered only by natural sunlight. Serum immunoglobulin E (IgE) levels were measured in 39 patients, and 21 (53.8%) patients showed elevated IgE levels. Oral antihistamine (48.1%) was the most widely used treatment, followed by oral cyclosporine (15.4%) and phototherapy (11.5%).
Conclusion
SU is an uncommon type of photodermatosis in Korea, with a greater prevalence in men. In this study, UVA was found to be the predominant action spectrum responsible for SU.
