[Allergic contact urticaria caused by a chameleon. Expression of sensitization to Ficus benjamina]

A 31-year-old man presented with a long history of rhinoconjunctivitis and sneezing that lasted from March to May. The man kept a chameleon (Chamaeleo calyptratus) as a pet and reported about recurrent urticarial lesions, erythema, and itch after skin contact with the animal. The reactions started within a few minutes and were restricted specifically to the contact sites with the animal's claws. No comparable reactions occurred in other subjects. Allergy testing confirmed allergy to hazel, alder, birch, and ash pollen, and additionally revealed sensitization to house dust mite, cat, and Ficus benjamina. Apparently the contact dermatitis originated from passive transfer of Ficus benjamina allergens to the patient's skin by the reptile which habitually climbed on a big Ficus benjamina tree in the patient's home, thereby contaminating its claws with the plant's allergenic milky sap. Careful examination revealed strong perforation of many leaves by the pointed claws. The patient denied respiratory symptoms from Ficus benjamina and intolerance of Ficus-associated fruits.