In vitro and in vivo cross-reactivity studies of legume allergy in a Mediterranean population.
BACKGROUND
Legume allergy, mainly to lentils and chickpeas, is the fifth most common cause of food allergy in Spanish children. Serological cross-reactivity among legumes is frequent, but its clinical relevance is controversial. The aim of this study was to investigate the cross-reactivity among lentils, chickpeas, peas, white beans and peanuts and its clinical relevance in pediatric patients.


METHODS
Fifty-four children with clinical allergy to legumes were included. Cross-reactivity was evaluated by ELISA inhibition experiments and oral food challenges to legumes. SDS-PAGE immunoblots were conducted with raw and boiled legume extracts.


RESULTS
ELISA inhibition experiments demonstrated more than 80% inhibition with lentil, chickpea and pea extracts. Immunoblots performed with raw legume extracts (lentil, chickpea and pea) and individual sera revealed that more than 50% of the sera identified an allergen with approximately 50 kDa in all three legume extracts. In all three boiled extracts an intense band at approximately 50 kDa was visualized using a serum pool. The oral legume challenges demonstrated that 37 children (69%) were allergic to 2 or more legumes (median 3 legumes). The most frequent associations were allergy to lentils and chickpeas (57%), allergy to lentils and peas (54%) and allergy to lentils, chickpeas and peas (43%).


CONCLUSIONS
In vitro inhibition experiments demonstrated a high degree of cross-reactivity among lentils, chickpeas and peas. Food challenges confirmed that clinical allergy to all three legumes is frequent in our cohort of Spanish children.
Martínez San Ireneo
Mercedes
M
Servicio de Alergia, Hospital Ntra. Sra. del Prado, Talavera de la Reina, Spain.
Ibáñez
María Dolores
MD
Fernández-Caldas
Enrique
E
Carnés
Jerónimo
J
D000293:Adolescent; D000485:Allergens / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D029863:Cicer / Q000009:adverse effects / Q000737:chemistry / Q000276:immunology; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D007887:Fabaceae / Q000009:adverse effects* / Q000145:classification / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007223:Infant; D027806:Lens Plant / Q000009:adverse effects / Q000737:chemistry / Q000276:immunology; D008297:Male; D018532:Pisum sativum / Q000009:adverse effects / Q000737:chemistry / Q000276:immunology; D013030:Spain / Q000453:epidemiology
D000485:Allergens