Phytophotodermatitis From Lime Margaritas on a Mexico Vacation

Area of Science:

• Dermatology
• Toxicology
• Photobiology

Background:

• Phytophotodermatitis is a skin reaction caused by furocoumarins from plants and subsequent sun exposure.
• It is a form of contact dermatitis with varied clinical presentations.
• Citrus plants are common sources of photosensitizing furocoumarins.

Observation:

• A 34-year-old patient presented with an asymptomatic, hyperpigmented patch on their back after a beach vacation.
• The lesion's appearance was irregular and atypical.
• The patient recalled consuming a lime margarita and rubbing their hand on their back.

Findings:

• The clinical presentation and history were consistent with phytophotodermatitis.
• The reaction was attributed to furocoumarins from lime contacting the skin, followed by sun exposure.
• The patient's back patch was a result of autoinoculation from hand to back.

Implications:

• Accurate diagnosis of phytophotodermatitis requires a detailed patient history, including recent sun exposure and potential contact with phytotoxic plants.
• Awareness of varied presentations is crucial to avoid misdiagnosis and unnecessary treatments like topical corticosteroids.
• This case underscores the importance of a comprehensive physical examination and patient history in diagnosing cutaneous reactions.