Sp. Patil et al., Chickpea: a major food allergen in the Indian subcontinent and its clinical and immunochemical correlation, ANN ALLER A, 87(2), 2001, pp. 140-145
Background: The food allergy pattern of a country is influenced by the food
s most commonly consumed. In India, the majority of the population consumes
a vegetarian diet made up of pulse (legumes), cereals, and vegetables. In
contrast to many western countries, chickpea preparations are consumed in l
arge quantities in India. This study reports for the first time chickpea hy
persensitivity reactions diagnosed with in vivo and in vitro tests.
Methods: One thousand four hundred patients visiting allergy clinics were r
andomly selected for the study. Those patients reporting an allergic reacti
on on every occasion after eating chickpea were considered history-positive
. Modified prick tests were performed with chickpea and other members of th
e legume family on all these patients. The claims of the history-positive p
atients were verified with double-blind, placebo-controlled food challenges
(DBPCFCs). Proteins in chickpea extracts were separated by sodium dodecyl
sulfate-polyacrylamide gel electrophoresis and transferred on nitrocellulos
e paper. Serum specimens from history-positive patients were analyzed by im
munoblot and ELISA. To verify the IgE specificity, an immunoblot inhibition
assay was also performed.
Results: Of the 1,400 patients screened, 142 patients were history-positive
to some food and 59 of these implicated chickpeas. Forty-one patients were
skin test-positive and 31 were DBPCFC-positive for chickpea. The predomina
nt symptoms after chickpea ingestion were respiratory. The ELISA results di
d not correlate well with the DBPCFC results; however, the skin test result
s correlated with DBPCFC in 75% of patients. Immunoblot analysis showed tha
t 70, 64, 35, and 26 kD proteins were major allergens.
Conclusions: Chickpea is an important source of allergen that can cause IgE
-mediated hypersensitivity reactions ranging from rhinitis to anaphylaxis.