Airborne contact dermatitis from Ambrosia deltoidea (triangle-leaf bursage).

3 cases of contact dermatitis due to exposure to airborne allergens from Ambrosia deltoidea (triangle-leaf bursage) are presented. Although airborne plant dermatitis was suggested in each case by a history of aggravation of the rash by outdoor exposure and typical skin lesions, patch testing with an oleoresinous extract of A. deltoidea leaves identified the source of the sensitizer, not previously reported.

Keratoacanthoma developing in sites of previous trauma: a report of two cases and review of the literature.

Keratoacanthoma is a common benign squamous neoplasm that only rarely progresses to metastatic carcinoma. The cause of keratoacanthoma is unclear; however, suspected causes include ultraviolet light, genetic factors, immunosuppression, chemical carcinogens, viruses, and trauma. Keratoacanthomas have been reported only rarely to arise in sites of previous trauma.