A 40-year-old man presented to an American allergy clinic with a two-day history of burning and irritation on both hands. The day before, he had squeezed the juice from 12 limes with his hands and then attended an outdoor football game without using sunscreen. On examination, there was confluent erythema from the dorsal surfaces of the thumbs to the medial surfaces of the index fingers on both sides and scattered areas on the knuckles and other fingers. There was no erythema under the ring finger; there was a small blister at the base of the left thumb. Vishaka Ravishankar Hatcher, MD, of Joint Base San Antonio, and Charles Kent Miller, MD, of Nellis Air Force Base Medical Center, reported the case in the New England Journal of Medicine.
Based on the patient's medical history and examination data, he was diagnosed with phytophotodermatitis. This is a phototoxic non-immunological skin reaction caused by furocoumarins, photosensitizing compounds found in lime, celery, parsley, hogweed, and other plants, and ultraviolet light. The man was prescribed a cream with the glucocorticoid triamcinolone and emollients. Four days after the juice's action, another blister appeared on his right thumb. Hyperpigmentation and peeling appeared two weeks later, and the skin returned to normal within a few months.
