Denise-Anne Moneret-Vautrin

Cross-allergenicity of peanut and lupine: the risk of lupine allergy in patients allergic to peanuts.

BACKGROUNDnPeanut allergy is common, but cross-allergy between legumes is rare. Proteins from Lupinus albus are increasingly eaten in the form of seeds or additives to wheat flour. The risk of cross-allergenicity is still insufficiently known.nnnOBJECTIVEnWe sought to study the risk of cross-allergy to lupine in patients allergic to peanut and to study lupine allergenicity.nnnMETHODSnTwenty-four patients allergic to peanuts were studied by means of skin prick tests with native lupine flour from Lupinus albus. Double-blind oral challenge tests were performed with lupine flour and peanut in 8 of these patients. Specific IgEs were assayed for peanut, lupine flour, and pollen in 6 sera. RAST inhibition tests for lupine pollen by peanut were performed on 4 of these sera. Peanut and lupine flour immunoblots were carried out for 6 sera, and crossed immunoblot inhibitions for peanut by lupine flour and lupine flour by peanut were carried out for 2 sera.nnnRESULTSnThe skin prick test responses with lupine flour were positive in 11 (44%) subjects. The challenge test responses were positive in 7 of 8 subjects at the same doses as with peanut. The major lupine flour allergen (molecular mass, 43 kd) is present in peanuts. The RAST inhibition and immunoblot tests indicated cross-reactivity of peanut with the lupine flour and pollen.nnnCONCLUSIONSnThe risk of crossed peanut-lupine allergy is high, contrary to the risk with other legumes. The inclusion of 10% lupine flour in wheat flour without mandatory labeling makes lupine a hidden allergen, presenting a major risk of cross-reaction in subjects already allergic to peanut products. A high sensitizing potential can also be postulated for this legume.

Les allergies aux matériaux utilisés en orthodontie

Les allergies de contact dans la cavite buccale sont relativement rares, mais elles ne doivent pas etre ignorees. Leurs manisfestations cliniques sont variees : urticaire, stomatites et cheilites, œdeme de Quincke, et il convient de les differencier dautres pathologies. Les principaux haptenes et allergenes liberes par les appareils orthodontiques proviennent des metaux : nickel, chrome, cobalt, des composants des resines et du latex.Si les reactions allergiques aux metaux et a la resine guerissent spontanement avec leviction de lallergene, lhypersensibilite immediate au latex peut avoir des consequences plus graves, voire irreversibles.Une collaboration etroite entre orthodontiste et allergologue est donc necessaire au cours de toutes les etapes de la prise en charge du patient afin doptimiser les therapeutiques.