Endotypes of pollen-food syndrome in children with seasonal allergic rhinoconjunctivitis: a molecular classification.

BACKGROUND: Pollen-food syndrome (PFS) is heterogeneous with regard to triggers, severity, natural history, comorbidities, and response to treatment. Our study aimed to classify different endotypes of PFS based on IgE sensitization to panallergens. METHODS: We examined 1271 Italian children (age 4-18 years) with seasonal allergic rhinoconjunctivitis (SAR). Foods triggering PFS were acquired by questionnaire. Skin prick tests were performed with commercial pollen extracts. IgE to panallergens Phl p 12 (profilin), Bet v 1 (PR-10), and Pru p 3 (nsLTP) were tested by ImmunoCAP FEIA. An unsupervised hierarchical agglomerative clustering method was applied within PFS population. RESULTS: PFS was observed in 300/1271 children (24%). Cluster analysis identified five PFS endotypes linked to panallergen IgE sensitization: (i) cosensitization to ≥2 panallergens ('multi-panallergen PFS'); (ii-iv) sensitization to either profilin, or nsLTP, or PR-10 ('mono-panallergen PFS'); (v) no sensitization to panallergens ('no-panallergen PFS'). These endotypes showed peculiar characteristics: (i) 'multi-panallergen PFS': severe disease with frequent allergic comorbidities and multiple offending foods; (ii) 'profilin PFS': oral allergy syndrome (OAS) triggered by Cucurbitaceae; (iii) 'LTP PFS': living in Southern Italy, OAS triggered by hazelnut and peanut; (iv) 'PR-10 PFS': OAS triggered by Rosaceae; and (v) 'no-panallergen PFS': mild disease and OAS triggered by kiwifruit. CONCLUSIONS: In a Mediterranean country characterized by multiple pollen exposures, PFS is a complex and frequent complication of childhood SAR, with five distinct endotypes marked by peculiar profiles of IgE sensitization to panallergens. Prospective studies in cohorts of patients with PFS are now required to test whether this novel classification may be useful for diagnostic and therapeutic purposes in the clinical practice.

Effectiveness of Ischia thermal water nasal aerosol in children with seasonal allergic rhinitis: a randomized and controlled study.

Allergic rhinitis is characterized by local inflammation. Nasal lavage may be a useful treatment, however, there are few studies on this topic. This study aims to evaluate the effects of Ischia thermal water nasal irrigation on allergic rhinitis symptoms and airway inflammation during the period of natural exposure to Parietaria pollen in children with allergic rhinitis and intermittent asthma. Forty allergic children were randomly divided into two groups: the first group (Group 1) practiced crenotherapy with thermal water aerosol for 15 days per month, for three consecutive months, the control group (Group 2) was treated with 0.9% NaCl (isotonic) solution. In addition, all children were treated with cetirizine (0.5 gtt./kg/day once daily). Nasal symptom assessment, including Total Symptom Score (TSS), spirometry, and exhaled nitric oxide (FeNO) were considered before the treatment (T0), at the end of the treatment (T1) and again 2 weeks after the end of the treatment (T2). The study was registered in the Clinical Trials.gov (NCT01326247). Thermal water significantly reduced both TSS and FeNO levels and there was a significant relationship between reduction of nasal symptoms and FeNO values at the end of treatment with thermal water. In conclusion, this study shows that nasal crenotherapy with the hypermineral chloride-sodium water of Ischia was effective in children with seasonal allergic rhinitis based on the sensitivity to Parietaria. These results demonstrate that this natural treatment may be effective in a common and debilitating disease such as the allergic rhinitis.