4th August 2020

A 23-year-old lady with chronic contact dermatitis has undergone several rounds of patch testing with no definitive results

A 23-year-old lady with chronic contact dermatitis has undergone several rounds of patch testing with no definitive results. She continues to experience erythema, swelling, pruritus on her arms. The chronic nature of her disease has also led to scaling of the skin and ulceration in several areas. She has received little benefit from the topical corticosteroids. She is becoming increasingly distressed by the symptoms, and she would like a definitive diagnosis. At this point, what is the most important investigation to offer this patient?

Select the SINGLE most appropriate option from the list below. Select ONE option only.