Is it necessary to test both english walnut and black walnut when evaluating for a walnut allergy?

English walnuts are the standard grocery store walnut, and are great for everyday baking and snacks. Compared to Black walnut, they are mild, sweet, and buttery. Black walnuts are used in some specialty desserts, but are less commonly used. The two walnuts are greatly cross-reactive, so testing for ...

Studies show high, near-complete cross-reactivity between English walnuts (Juglans regia) and black walnuts (Juglans nigra), with very similar allergenic proteins (like Jug r 1, a 2S albumin) causing reactions in patients sensitive to either.

The patient in question must be reacting to a unique prot...