Well, it’s that time of year again. The season of Flathead cherries from Montana, Rainier cherries from Washington and Door County cherries from Wisconsin. Pie, cobbler, jam, jelly, ice cream, turnovers, cake, sauce, muffins, bars, clafoutis, scones, and, of course, fresh cherries are some of the delicious results of this season.
What if you are allergic to cherries? It’s the pits!
Cherry allergy is frequently reported along with other fresh fruits in the Rosaceae family in the Prunoideae subfamily. These include cherry, peach, apricot and plum. Ingesting these fresh fruits can lead to oral allergy syndrome now called Pollen-Food Allergy Syndrome. The symptoms are mouth itching, with or without mild swelling of the lips, tongue, palate (roof of mouth) and pharynx (throat). Rarely is anaphylaxis associated with Pollen-Food Allergy Syndrome.
The major allergen that spans these fruits is a 13 kDa (kiloDalton) size protein and is common among them; this particular protein is not shared with grass or birch-tree pollen. From 19 to 29% of birch pollen-allergic patients report cherry allergy. The allergen in sweet cherries has been identified as Pru av 1 (pathogen-related protein 10 that cross reacts with birch tree pollen), Pru av 2 (23 kDa thaumatin-like protein (TLP), a pathogen-related protein 5-similar to one in apples) and Pru av 4 (15 kDa Profilin protein also that cross reacts to birch trees and implicated in celery-mugwort-spice syndrome). Suffice it to say there are a lot of proteins in cherries that can lead to reactions.
Severe reactions such as anaphylaxis to cherry have been reported but are unusual. Curiously, a 12-year-old boy in Italy suffered anaphylaxis after he ate cherries (or peach), then exercised. Food-dependent exercise-induced anaphylaxis is rare.
The 3 approaches to testing for cherry allergy:
- Skin test with commercial extract of cherry
- Fresh/frozen cherry skin test
- Blood test for cherry specific IgE
The most helpful test is the use of fresh or frozen cherry as the amount of cherry specific IgE antibody in blood can be too low to detect. During processing, sometimes the fragile proteins of fruit may be changed, affecting the skin test result of commercial extracts. The best “sensitivity and specificity” is obtained with fresh/ frozen cherry.
If you have had a reaction to cherry or other fruit, call Family Allergy & Asthma Care of Montana. I can assist in the diagnosis and individualized treatment plan for food allergies. PS, bring some fresh cherries for testing!
This information is solely for informational purposes and not intended as a substitute for consultation with a medical professional.