Guideline sources The following summarized guidelines for the evaluation and management of pollen-food allergy syndrome (PFAS) are prepared by our editorial team based on guidelines from the British Society for Allergy and Clinical Immunology (BSACI 2022), the German Society for Pediatric Allergology and Environmental Medicine (GPA/DDG/AWMF/VDOE/DGVS/GPGE/BVKJ/ GAI/DAAB/DGP/DKG/DGAKI/AeDA/DGHNO-KHC/DGKJ/DGE 2015), and the American Academy of Allergy, Asthma & Immunology (AAAAI/ACAAI 2014). 1 2 3 Guidelines 1. Screening and diagnosis Common triggers: Recognize that: typical birch-related triggers include raw apples, stone fruits, kiwi fruit, carrot, celery, soya milk, raw peanuts, and raw tree nuts (usually hazelnuts, almonds, and walnuts) symptoms can also occur when peeling potatoes or other root vegetables freshly prepared fruit/vegetable juices or smoothies, celery, soya milk, raw nuts, large quantities of roasted nuts, and concentrated nut products, can provoke more severe reactions. Diagnosis: Recognize that PFAS is a food allergy frequently affecting pollen-sensitized patients usually with a history of seasonal allergic rhinitis and is characterized by immediate-onset, mild-to- https://web.pathway.md/diseases/recTUekXwkSonNcYo 1/5 6/29/23, 11:16 PM Pollen-food allergy syndrome Pathway moderate oropharyngeal symptoms to plant foods, but only when raw. Consider diagnosing PFAS solely based on clinical history. Do not obtain further testing in patients with seasonal allergic rhinitis reporting characteristic immediate-onset mild symptoms to typical raw food triggers. C Differential diagnosis: distinguish PFAS from a primary allergy to peanuts, tree nuts or fruit, or an allergy to non-specific lipid transfer proteins, highly cross-reactive proteins present in most plant foods, because of the significant differences in management. 2. Diagnostic investigations Indications for allergy testing: Consider obtaining allergy tests to foods in the following situations: more severe or atypical symptoms to characteristic raw food triggers uncertainty whether reactions also occur to roasted hazelnuts, almonds, walnuts, Brazil nuts, or peanuts, either on their own or when present in composite foods, such as chocolates, spreads, desserts, and snacks triggers include other soy products or cooked/processed fruits/vegetables, such as smoothies and juices reactions are reported specifically to cashew, pistachio, or macadamia nuts. Do not obtain further testing in patients with seasonal allergic rhinitis reporting characteristic immediate-onset mild symptoms to typical raw food triggers. D Skin prick test: Obtain allergy tests to foods only to specifically reported triggers, including: Situation Guidance A positive prick-to-prick skin test using raw/unpeeled foods suggests PFAS Raw fruits and vegetables Test for sensitization to non-specific lipid- transfer proteins if severe or atypical reactions to fruits, or composite dishes are reported B A positive prick-to-prick skin test to soya milk together with a history of reactions to soya milk but not to soy-containing foods suggests PFAS Soya products Test for sensitization to Gly m 4 - PR10 allergen - and other soya allergens, including Gly m 5, 6, 8, if the test is positive but reactions are severe or reported to occur with all soy-containing foods B A positive skin prick test to hazelnut and negative prick-to-prick skin test to roasted hazelnut confirms a diagnosis of PFAS Hazelnut https://web.pathway.md/diseases/recTUekXwkSonNcYo 2/5 6/29/23, 11:16 PM Pollen-food allergy syndrome Pathway Test for sensitization to the hazelnut PR10 allergen Cor a 1, and seed storage proteins, including Cor a 9 and Cor a 14, if roasted hazelnut prick-to-prick skin test is positive but history strongly suggests PFAS Recognize that some hazelnut skin prick test extracts are enriched with Cor a 1 but can be used if prick-to-prick skin test is not available, provided a positive test is interpreted with caution and in conjunction with the symptom history B A negative skin prick test and typical PFAS symptoms confirm a diagnosis of PFAS Peanut, walnut, almond, Brazil nut Consider testing for sensitization to seed storage proteins in peanuts, i.e. Ara h 2, and if negative Ara h 1, 3, 6, walnuts, i.e. Jug r 1, and Brazil nuts, i.e. Ber e 1, if the above tests are positive or indeterminate B Recognize that these foods are unlikely to trigger PFAS Macadamia nut, cashew nut, pistachio nut Follow diagnostic pathways for tree nut allergy if symptoms are specifically reported to these foods. Oral food challenge: obtain oral food challenge to confirm a diagnosis of PFAS only if the history and diagnostic tests are inconclusive or when multiple foods are being avoided. B Immunoglobulin E testing: suspect PFAS and obtain specific IgE testing to pollens in patients experiencing limited oropharyngeal symptoms after ingestion of food antigens cross- reacting with pollen antigens. B 3. Medical management Pharmacotherapy: recognize that reactions following accidental exposure often resolve without medication and, although antihistamines may be needed, self-injectable epinephrine devices are rarely required. E Specific immunotherapy: As per BSACI 2022 guidelines, do not offer specific immunotherapy to the sensitizing pollen for the treatment of patients with PFAS. Insufficient evidence to recommend oral immunotherapy using fresh foods or component allergens. D As per DGAKI 2015 guidelines: Offer SC or sublingual immunotherapy using pollen allergens in patients with pollen- associated food allergy only in the case of concomitant pollen-related respiratory https://web.pathway.md/diseases/recTUekXwkSonNcYo 3/5 6/29/23, 11:16 PM Pollen-food allergy syndrome Pathway symptoms. B Offer oral immunotherapy using food allergens in patients with pollen-associated food allergy only in the context of controlled studies. B 4. Nonpharmacologic interventions Dietary avoidance: As per BSACI 2022 guidelines, provide individually tailored dietary advice to avoid nutritional imbalance, minimize anxiety and consequent unnecessary food restrictions and improve quality of life. B As per AAAAI 2014 guidelines, advise dietary avoidance of raw fruits, vegetables, or both, with the extent of food avoidance depending on the severity of oropharyngeal symptoms for the management of PFAS. B Clinical findings Symptoms Triggers Burning sensation in the throat Raw fruits Itching in the mouth Raw nuts Itchy ears Raw vegetables Itchy eyes Ocular exam Itchy nose Lip swelling Conjunctivitis Nasal congestion Integument exam Rhinorrhea Throat itching Angioedema Past medical history Allergic conjunctivitis Allergic rhinitis Anaphylaxis Asthma Atopic dermatitis Atopy Pollen allergy Head and neck exam Facial erythema Oral blisters Oral vesicles Tongue swelling Serological findings serum peanut-specific IgE https://web.pathway.md/diseases/recTUekXwkSonNcYo 4/5 6/29/23, 11:16 PM Pollen-food allergy syndrome Pathway References 1. Isabel J Skypala, Hannah Hunter, Mamidipudi Thirumala Krishna et al. BSACI guideline for the diagnosis and management of pollen food syndrome in the UK. Clin Exp Allergy. 2022 Sep;52 9 1018 1034. Open 2. Hugh A Sampson, Seema Aceves, S Allan Bock et al. Food allergy: a practice parameter update-2014. J Allergy Clin Immunol. 2014 Nov;134 5 1016 25.e43. Open 3. Margitta Worm, Imke Reese, Barbara Ballmer-Weber et al. Guidelines on the management of IgE- mediated food allergies: S2k-Guidelines of the German Society for Allergology and Clinical Immunology DGAKI in collaboration with the German Medical Association of Allergologists AeDA , the German Professional Association of Pediatricians BVKJ , the German Allergy and Asthma Association DAAB , German Dermatological Society DDG , the German Society for Nutrition DGE , the German Society for Gastroenterology, Digestive and Metabolic Diseases DGVS , the German Society for Oto-Rhino- Laryngology, Head and Neck Surgery, the German Society for Pediatric and Adolescent Medicine DGKJ , the German Society for Pediatric Allergology and Environmental Medicine GPA , the German Society for Pneumology DGP , the German Society for Pediatric Gastroenterology and Nutrition GPGE , German Contact Allergy Group DKG , the Austrian Society for Allergology and Immunology GAI , German Professional Association of Nutritional Sciences VDOE and the Association of the Scientific Medical Societies Germany AWMF . Allergo J Int. 2015;24 256 293. Open https://web.pathway.md/diseases/recTUekXwkSonNcYo 5/5