Patch testing first might be a good idea . talk ) 22 : 15, 26 October 2008 ( UTC)
12.
Patch testing may be indicated if allergies are suspected ( e . g . a strong relationship between certain foods and episodes of ulceration ).
13.
Patch testing helps identify which substances may be causing a delayed-type allergic reaction in a patient, and may identify allergens not identified by blood testing or skin prick testing.
14.
Patch testing is the " gold standard " diagnostic tool for Ni-ACD . In this sense, a positive patch test to nickel establishes that the subject has been previously exposed and is therefore sensitized to nickel.
15.
Using histology on its own is insufficient, as these findings have been acknowledged not to distinguish, and even positive patch testing does not rule out the existence of an irritant form of dermatitis as well as an immunological one.
