Allergy to Pumpkin Seeds

Allergic reactions due-to-pumpkinseed (Cucurbita pepo) are infrequent despite its widespread use in a variety of foods. Allergens responsible have not been well studied. Three patients from outpatient clinic with a suspected allergic reaction after ingestion of pumpkinseeds were evaluated. Two of them had anaphylaxia and the third one had oral allergy syndrome (OAS) and abdominal pain. All tolerated pumpkin-fruit and other cucurbits. We perform skin prick tests (SPT), prick by prick (PP), ImmunoCAP to inhalants, fruits, pumpkinseed and nuts and IgE-Immunoblotting to peel, pulp and seed from pumpkin and nuts involved. SPT, PP and ImmunoCAP to pumpkinseeds were positive in all patients, and negative to pumpkin-fruit and profilins. One patient was positive for cashew and pistachio and the second to pineseeds. The third patient was positive for Pru p 3 and other LTPs from nuts. IgE-immunoblotting from the two patients with anaphylaxia revealed a common protein band of 6kDa in pumpkin and pineseeds. Additional bands were identified in pumpkinseed (34, 48 kDa), peel and pulp extracts, pistachio, cashew and tigger nut. The third patient sensitized to LTP identified bands of 26 and 30 kDa in pumpkinseed-extract, and different bands in pumpkin peel and pulp, including a 9 kDa protein. We present three patients allergic to pumpkinseeds with tolerance to pumpkin and other cucurbit-fruits. The responsible allergen could be the 6 kDa protein identified by both patients with anaphylaxia. Regarding the third patient sensitized to LTPs, two proteins of 26 kDa and 30 kDa were identified.