What tests do you need to test for dermatitis and eczema?

Dermatitis, eczema, in addition to skin examination, should also do the following inspection:
1 、 hematology and serology: peripheral blood eosinophilia, T lymphocyte (especially Ts) decreased, serum IgE content increased significantly.

2 、 skin test is positive for some allergens (such as fungi, pollen, hair crumbs) allergic reactions. Intradermal tests such as tuberculin and Candida (delayed hypersensitivity reactions) are often negative or weakly positive.
With a blunt zoned skin 3, white skin scratch test, skin white scratches (normal red).