1/2. Late diagnosis of tree nut and sesame allergy in patients previously sensitized but tolerant to peanut.BACKGROUND: Recent studies have indicated that tolerance to peanut can occur in patients with a history of peanut allergy. Tree nut and sesame allergies have been reported to occur at increased incidence in patients with peanut allergy. Although the coexistence may be simply due to a predisposition to food allergy in these individuals, cross-reactivity has been demonstrated between peanut and tree nuts and between peanut and sesame seed. OBJECTIVE: To describe 3 patients previously sensitized but tolerant to peanut who were subsequently diagnosed as having either tree nut or sesame allergy. methods: All the patients had a clinical history of peanut sensitivity and underwent follow-up peanut skin testing to commercial extracts using a bifurcated needle followed by a graded peanut challenge. One patient had a previous positive radioallergosorbent test reaction to sesame and underwent a graded sesame challenge. RESULTS: All the patients had negative peanut challenge results. Two patients subsequently had exposure to tree nuts at home and had systemic reactions and positive skin test reactions to the incriminated tree nut. One patient had a positive challenge reaction to sesame. CONCLUSION: Demonstration of tolerance to peanut may falsely reassure patients and physicians that patients no longer need to avoid tree nuts or sesame. Tree nut and sesame allergies can exist or develop in patients despite the development of tolerance to peanut.- - - - - - - - - - ranking = 1keywords = tree (Clic here for more details about this article) |
2/2. carica papaya pollen allergy.BACKGROUND: carica papaya (CP) trees are widely cultivated in tropical and subtropical areas; however, CP pollen allergy has not been previously described. OBJECTIVE: To study patients with CP pollen hypersensitivity. methods: A CP pollen extract was elaborated. skin prick tests (SPTs) with this extract, as well as with commercial papaya fruit and papain extracts, were performed. Specific IgE levels to CP pollen, papaya fruit, and papain were determined. Specific conjunctival challenge tests to the CP pollen extract were also performed. RAST inhibition studies among CP pollen, papaya fruit, and papain were carried out. Twenty atopic patients were used as a control group for in vivo and in vitro tests. RESULTS: Six patients with clinical histories of seasonal rhinoconjunctivitis or bronchial asthma in relation to CP trees exposure, suggestive of IgE-mediated respiratory allergy, were studied. Commercial SPT and specific serum IgE to papaya fruit and papain were positive in our patients. An IgE-mediated hypersensitivity to a CP pollen extract was demonstrated in all patients, by means of SPTs, specific serum IgE determinations, and conjunctival challenge tests. Control atopic subjects showed negative SPTs, specific IgE, and conjunctival challenge tests to the CP pollen extract. On RAST inhibition studies using CP pollen extract in solid phase, a significant crossreactivity was found among CP pollen, papaya fruit, and papain. CONCLUSIONS: Our study suggests that papaya flower pollen is able to induce respiratory IgE-mediated allergy. The existence of common allergens among papaya flower pollen, papaya fruit, and papain has been demonstrated by RAST inhibition.- - - - - - - - - - ranking = 0.22222222222222keywords = tree (Clic here for more details about this article) |