Background Mild oropharyngeal symptoms to peanut/hazelnut occur in ~30% of patients with pollen-food syndrome (PFS). Component tests are considered a useful adjunct to the diagnosis and may help differentiate PFS from those at a risk of anaphylaxis due to storage protein/lipid transfer protein (LTP) sensitisation.
Aims To assess concordance between component tests and clinical history in suspected PFS to peanut/hazelnut in a specialist clinic.
Methods Adult patients were classified into PFS (group 1, n=69) and PFS with mild systemic symptoms (group 2, n=45) based on clinical history. Specific IgE (sIgE) of â‰¥0.35â€‰kUA/L was considered positive as per manufacturersâ€™ recommendation. Kappa (Îº) inter-rater agreement was calculated for concordance between clinical classification and test profiles.
Results Group 1 hazelnut: 85% monosensitised to Cor a1, 12% to storage protein/s or LTP and 3% negative to all components. Group 1 peanut: 41% monosensitised to Ara h8, 44% to storage protein/s or Â±LTP and 15% negative to all components. Group 2 hazelnut: 67% monosensitised to Cor a1, 16% sensitised to storage protein/s and 17% negative to all components. Group 2 peanut: 19% monosensitised to Ara h8, 62% sensitised to storage protein/s and/or LTP and 19% negative to all components.
SIgE to Ara h8 and Cor a1 were greater in group 1 versus group 2: (median (IQR) kUA/L; hazelnut: 12.1 (7.8-25.2) vs 2.4 (0.36-6.3), p<0.001; peanut: 2.4 (0.10-21.1) vs 0.3 (0-3), p<0.01)).
Conclusion Concordance between component tests and clinical history for adults with PFS was good for hazelnut (Îº=0.63) but poor for peanut (Îº=âˆ’0.12). Food challenges are warranted in discordant cases for an accurate diagnosis.
- component tests
- peanut allergy
- hazelnut allergy
- pollen food syndrome