D2.284 - Eat the fruit, do not swallow the seed: A rare case of Cucurbitaceae allergy causing anaphylaxis
Case report
| Allergen | Diameter (mm) | Allergen | Diameter (mm) |
|---|---|---|---|
| Pumpkin seeds | 8 | Pumpkin pulp | 0 |
| Melon seeds | 9 | Melon pulp | 0 |
| Watermelon seeds | 11 | Watermelon pulp | 0 |
| Black grape seeds | 0 | Black grape pulp | 0 |
| Zucchini seeds | 0 | Zucchini pulp | 0 |
| Blue poppy | 0 | ||
| Quinoa | 0 | ||
| Chia | 0 | ||
| Flaxseed | 0 | ||
| Sesame | 0 | ||
| Mustard seed | 0 |
Seeds are a common component of our daily diet and are recommended for their health benefits, including anti-inflammatory and antioxidant effects. However, with increasing consumption, various allergic reactions have been observed, with anaphylaxis being the most frequently encountered life-threatening reaction.
CASE REPORT
A 4-year-old male patient presented with symptoms of anaphylaxis, including coughing, respiratory distress, facial swelling, and rash, after consuming watermelon ice cream. The patient’s history revealed an anaphylactic reaction to pumpkin seeds at the age of 2 years; consequently, pumpkin was completely excluded from his diet. Prick-to-prick (PTP) testing revealed strong positive reactions to pumpkin, watermelon, and melon seeds, whereas PTP tests for the pulp of these fruits were negative. (Table.1)
After obtaining parental consent, OPTs were performed 1 month apart using separate watermelon and pumpkin pulp, following the recommended protocol from a previous report. The tests were completed in three steps at 20-min intervals, with incremental doses of 5 g, 30 g, and 65 g, reaching a total of 100 g of fruit pulp. After a 4-hour observation period, no reactions were observed. Both foods were subsequently added to the patient’s diet.
Component-resolved diagnostic (CRD) testing showed no significant pollen sensitivity that could suggest cross-reactivity. (Table.2) Based on these findings, the patient was diagnosed with a severe anaphylactic reaction to pumpkin and watermelon seeds.
CONCLUSIONS
Instances of allergic reactions to seeds are increasing. Foods that are not typically considered allergenic can cause severe reactions. Our case represents the second reported instance of watermelon seed allergy worldwide and the first documented case of melon seed sensitivity in the literature. In this report, we emphasize the importance of accurately recording patient history and conducting diagnostic testing for devising appropriate treatment plans, preventing unnecessary dietary restrictions, and providing education on the use of adrenaline autoinjectors.
