There are 2 allergens associated with an allergy to chillis. Cap a 1 is an osmotin (and thaumatin) like protein which is used in pathogen defense in the plant.
Cap a 2 is a profilin protein used in the plant for cell development.
Allergy to chilli peppers is sometimes linked to Celery-Birch-Mugwort-Spice Syndrome.
Other plants which contain thaumatin like proteins are kiwi, apple, banana, cherry and peach. If your allergy is linked to this protein then you may have allergic reactions to these fruits.
Chilli allergy is broadly linked to other fruit profilin allergies. Allergy to orange, melon, watermelon, tomato, banana, pineapple and lychee may be considered as a marker of profilin hypersensitivity.