Phytophotodermatitis Due to Fig Tree Sap Activated by Ultraviolet Light: A Case Report

Abstract

Phytophotodermatitis is a dermatological reaction caused by exposure to certain plants, which becomes activated upon subsequent exposure to sunlight. This can frequently result in a rash. Typically, supportive treatment is recommended. In this report, we describe the case of phytophotodermatitis in a 57-year-old man who experienced a painful rash with streaked lesions following the pruning of a fig tree during the summer. The patient, with no significant medical history, presented to the emergency department in July with a painful, streaked rash on both forearms. The lesions appeared overnight, predominantly on areas of skin exposed while sleeping. The patient denied contact with potential irritants and had not engaged in recent travel or altered his usual habits. Laboratory tests, including complete blood count and markers of inflammation, showed no abnormalities. A thorough patient history revealed recent fig tree pruning, a task usually undertaken in winter. The diagnosis of phytophotodermatitis was made based on the characteristic skin lesions and the patient's history of exposure to fig tree sap. Treatment with antihistamines led to improvement in symptoms, and the patient was discharged with a week-long course of antihistamines and advice to avoid sunlight and contact with fig trees. This case underscores the importance of a detailed medical history, especially in the context of dermatological lesions, to accurately diagnose and treat conditions like phytophotodermatitis.

Keywords: furanocoumarins; light sensitizing; painful rash; phytophotodermatitis; reaction by plants.

Figure 1. Supine (A) and pronated (B) arms showing the rash consequence of phytophotodermatitis