Phytophotodermatitis

Author Affiliation
Liza G. Smith, MD Baystate Medical Center, Department of Emergency Medicine, Springfield, Massachusetts
Christopher Kabhrel, MD Massachusetts General Hospital, Department of Emergency Medicine, Boston, Massachusetts

Case report
Discussion

CASE REPORT

A 22-year-old college student presented to the emergency department with a painful rash to her left upper extremity. She had returned from a spring-break trip to Ecuador the day prior to presentation and the rash had developed on the third day of her six-day stay. On further history, she endorsed squeezing limes into guacamole on the first day of her trip and did recall getting the juice on her arm, as well as spending many hours sunbathing. Due to her history of exposure to lime juice and the particular distribution of her rash, demonstrating a splash pattern with evidence of direct transfer across the flexor surfaces of her elbow, a diagnosis of phytophotodermatitis was made.

DISCUSSION

Phytophotodermatitis is a cutaneous reaction resulting from the interaction between sensitizing botanical substances and ultraviolet radiation. It is a direct phototoxic reaction entirely independent of the immune system. It typically presents as a painful, erythematous and sometimes blistering rash, often in linear, streaking patterns isolated to sun-exposed areas of skin.1

Several plant families are known to elicit phototoxic reactions, and one of the most commonly responsible chemical agents is furocoumarin, particularly the psoralen isomers, found in citrus fruits, notably lemons and limes.2

The pain is due to necrosis of the involved epidermis, and treatment is mainly symptomatic. Non-steroidal anti-inflammatory medications may be helpful for the pain, and topical steroids may be used if the eruption is severe. Residual hyperpigmentation is common.2

Footnotes

Section Editor: Shadi Lahham, MD, MS

Full text available through open access at http://escholarship.org/uc/uciem_cpcem

Address for Correspondence: Liza G. Smith, MD, Baystate Medical Center, 759 Chestnut Street Springfield, MA 01199. Email: Liza.SmithMD@BaystateHealth.org. 1:146 – 147

Submission history: Revision received October 3, 2016; Submitted January 9, 2017; Accepted January 11, 2017

Conflicts of Interest: By the CPC-EM article submission agreement, all authors are required to disclose all affiliations, funding sources and financial or management relationships that could be perceived as potential sources of bias. The authors disclosed none.

REFERENCES

1. Friedman BT, Harper R, Glucksberg A, et al. In the Limelight. J Emerg Med. 2016;50(3):504-5.

2. Kung AC, Stephens MB, Darling T. Phytophotodermatitis: bulla formation and hyperpigmentation during spring break. Mil Med. 2009;174(6):657-61.

Image
An erythematous, blistering rash (arrow) demonstrating a splash pattern with evidence of direct transfer across the flexor surface of the elbow.