Peach-induced contact urticaria is associated with lipid transfer protein sensitization.
BACKGROUND
Peach-induced contact urticaria is frequent in peach-allergic subjects.


OBJECTIVE
It was the aim of this study to detect whether contact urticaria is associated with a specific peach allergen.


METHODS
Ninety-two peach-allergic subjects were studied. Patients were diagnosed as being sensitized to lipid transfer protein (LTP; Pru p 3) or as having a pollen-food allergy syndrome induced by Pru p 1 and/or profilin, Pru p 4, on the basis of the results of a skin prick test containing these allergenic proteins in an isolated form. Specific IgE to peach extract was measured as well. Contact urticaria was confirmed by a contact test with intact, untreated peach. A contact test with nectarine was carried out as control.


RESULTS
Overall, contact urticaria was present in 21% of patients; the peach contact test scored positive in all cases. Contact urticaria was significantly more frequent in patients hypersensitive to LTP (63%) than in subjects with pollen-food allergy syndrome (6%; p < 0.001) and was not associated with a higher level of peach-specific IgE. In several cases, contact urticaria preceded the onset of food allergy by years. The contact test with nectarine scored negative in 5/5 cases.


CONCLUSIONS
Although the peach contact test was not performed in all subjects, and peach allergy was not confirmed by oral challenges, this study shows that peach-induced contact urticaria is associated with sensitization to peach LTP. The negative clinical history and contact test with nectarine along with the well-known high concentration of LTP in peach fuzz suggest that peach fuzz plays a role in the pathogenesis of contact urticaria.
Ambulatorio di Allergologia, Clinica San Carlo, Paderno Dugnano, Italia. r.asero@libero.it
Riccardo
R
Asero
D000485:Allergens / Q000276:immunology; D052179:Antigens, Plant / Q000276:immunology; D002352:Carrier Proteins / Q000276:immunology*; D003877:Dermatitis, Contact / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D006801:Humans; D008297:Male; D010940:Plant Proteins / Q000276:immunology; D027861:Prunus / Q000737:chemistry / Q000276:immunology*; D012882:Skin Tests; D014581:Urticaria / Q000209:etiology / Q000276:immunology*
D000485:Allergens; D052179:Antigens, Plant; D002352:Carrier Proteins; D010940:Plant Proteins; C030363:lipid transfer protein