Allergic contact dermatitis to Parthenium hysterophorus mimicking actinic prurigo.

A 28‐year‐old unmarried woman presented with a 10‐year history of itchy papules and nodules over her extremities and nape of neck. Initially, there were summer exacerbations but then disease became persistent for the last 3 years. She also gave history of episodic, redness of eyes, eyelid pruritus and swelling along with mild facial edema. There was no personal or family history of atopy. Cutaneous examination revealed a predominantly monomorphic, symmetrical eruption of 4‐8 mm sized hyperpigmented, dome shaped firm papules involving the nape of the neck and upper back, and the dorsal aspect below knee and elbow, and the ‘V’ area of chest. The face, flexures, conjunctiva and oral mucosa were spared. A provisional clinical diagnosis of actinic prurigo was considered.