The key allergens in pineapple are Ana c 1 and Ana c 2.
Ana c 1 is a profilin protein, similar to that in banana and latex.
Ana c 2 is called bromelain. This has been known to cause IgE mediated allergies and symptoms most often related to the respiratory system. This biochemical is commonly extracted from pineapple and used in cosmetics and food production where it is frequently used as a meat tenderiser (which is why your lips may tingle when eating pineapple).
If you suffer from pineapple allergy and other foods mentioned in the cross reactivity section below you may suffer from Latex Food Syndrome.
If sensitised to pineapple you may also be allergic to banana and latex.