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Progressive pollen food syndrome


I have a 31 year-old female patient with a several year history of Oral Allergy Syndrome. This condition appears to be worsening in terms of the numbers of foods that are causing symptoms as well as severity--e.g. eating raw Kale cause edema of the palate, partially cooked Zucchini caused facial angioedema, oral itching from most of her triggering foods now frequently progresses to itching of nose and eyes.

Her diet is becoming restricted of fresh fruits and vegetables and she is an athlete who eats 5-7 servings of fruits vegetables per day. She cooks these foods when she can but prefers fresh (for the general health benefits as well as personal taste).

Aside from cooking when possible, avoiding when not possible, are there any other treatment approaches that have good evidence of efficacy?

As far as diagnostic procedures, aside from history and physical exam to define existing sensitivities, how should recommendations for those foods with high risk of developing a sensitivity be defined? (based on Pollen sensitivities?, other diagnostic approaches?)


We spoke to a few of our specialists and here is a response from Dr. Scott Sicherer.

Response: With pollen-food allergy syndrome (PFAS), it is not unusual to see increasing numbers of foods become problematic with time.  This is usually seen in people with strong positive pollen tests and allergy to multiple pollens. There also seems to be some progression in severity in her case, and this can also be observed.  In one large study, about 9% had symptoms beyond the mouth like she is now experiencing,  3% had systemic symptoms and 1.7% anaphylaxis.1  Allergists report spectrum of opinion on prescribing strict avoidance and epinephrine autoinjectors for PFAS, and this may be in response to individual histories.2 Given her progressive symptoms, she may deserve a discussion about carrying emergency medications, having caution in the amount she eats, and avoiding eliciting factors (exercise, alcohol, NSAIDS, etc) when eating the casual foods in raw forms. It is good for her that heated forms are always tolerated, reducing the concern that she is reacting to stable plant proteins.

Regarding diagnostics, we usually are able to work from the history and then document pollen sensitivity to confirm the connection between the pollen and the reaction history. There may be specific nuances in the history, or new issues that would warrant additional testing. Prick-prick testing with the raw food is an option.   Reactions to heated forms would raise suspicions that pollen-related allergy is not the cause, changing the approach significantly.

For typical PFAS, the foods triggering symptoms can vary from person to person and time to time based on the individual sensitivity, relation in time to the pollen season, and nuances such as the cultivar of the fruit and ripening.  I do not usually restrict “experimentation” of trying related foods gradually if the past reactions have been mild to identified foods, especially if there has been comfort in eating foods causing mild symptoms.  If reactions are more significant, additional testing or supervised challenge could be warranted.  

The easiest and recommended treatment to avoid symptoms is to heat the food, and avoid raw forms.  People with mild symptoms may not mind the symptoms and choose to eat the foods raw. Some people find relief with minimal heating, for example treating the raw fruit for a brief period in a microwave, retaining some crispness. Although antihistamines may reduce symptoms,3 using antihistamines specifically to attempt ingestion of the raw food is not a generally recommended approach;  there is a theoretical concern that it may promote ingestion of larger amounts leading to systemic reactions. However, there is no reason to restrict antihistamines for treatment of respiratory allergy. Oral and sublingual immunotherapy to specific fruits and subcutaneous immunotherapy (SCIT) to the trigger pollens has been investigated.4-6  There are limited and contradictory results regarding these approaches.  Pollen immunotherapy is not generally recommended solely for the treatment of PFAS, although a subset of patients treated may experience relief.7 One might presume that treatment with anti-IgE for asthma or chronic urticaria would also reduce PFAS symptoms, but this has not been studied.

1.  Ortolani C, Pastorello EA, Farioli L, Ispano M, Pravettoni V, Berti C, et al. IgE-mediated allergy from vegetable allergens. Ann. Allergy 1993; 71:470-6.
2.  Ma S, Sicherer SH, Nowak-Wegrzyn A. A survey on the management of pollen-food allergy syndrome in allergy practices. J. Allergy Clin.Immunol. 2003; 112:784-8.
3.  Bindslev-Jensen C, Vibits A, Stahl Skov P, Weeke B. Oral allergy syndrome; the effect of astemizole. Allergy 1991; 46:610-3.
4. Asero R. Effects of birch pollen-specific immunotherapy on apple allergy in birch pollen-hypersensitive patients. Clin Exp. Allergy 1998; 28:1368-73.
5.  Moller C. Effect of pollen immunotherapy on food hypersensitivity in children with birch pollinosis. Ann. Allergy 1989; 62:343-5.
6.  Kinaciyan T, Jahn-Schmid B, Radakovics A, Zwolfer B, Schreiber C, Francis JN, et al. Successful sublingual immunotherapy with birch pollen has limited effects on concomitant food allergy to apple and the immune response to the Bet v 1 homolog Mal d 1. J. Allergy Clin. Immunol. 2007; 119:937-43.
7. Sampson HA, Aceves S, Bock SA, James J, Jones S, Lang D, et al. Food allergy: a practice parameter update-2014. J Allergy Clin Immunol 2014; 134:1016-25 e43.

I hope this information is of help to you and your patient.

All my best.
Dennis K. Ledford, MD, FAAAAI