Allergy to kiwi: a double-blind, placebo-controlled food challenge study in patients from a birch-free area.
BACKGROUND
Allergy to kiwi fruit is being increasingly reported, but it has never been evaluated by means of a double-blind, placebo-controlled food challenge (DBPCFC) study.


OBJECTIVE
We sought to assess kiwi allergy on the basis of a DBPCFC and identify the patterns of allergen recognition in sensitized patients from a birch-free area.


METHODS
Forty-three patients with allergy symptoms who were sensitized to kiwi were evaluated by means of clinical history, skin tests, IgE determinations, and DBPCFCs. The pattern of allergen recognition was assessed by means of IgE immunoblotting. Sequence analysis of IgE-binding bands was performed by using Edman degradation.


RESULTS
DBPCFCs were performed in 33 patients; 4 patients had experienced severe anaphylaxis, and 6 patients declined informed consent. DBPCFC results were positive in 23 patients and negative in 10 patients. The most frequent clinical manifestation was oral allergy syndrome. Twenty-one percent of the patients were not allergic to pollen. Forty-six percent of patients experienced systemic symptoms, and this happened with higher frequency in patients not allergic to pollen (100%). Twenty-eight percent of the patients were sensitized to latex. The IgE-binding bands in kiwi extract more frequently recognized by patient sera were those of 30, 24, 66, and 12 kd, and they could not be associated with any pattern of kiwi-induced allergic reactions.


CONCLUSIONS
The results provide evidence that kiwi allergy is not a homogeneous disorder because several clinical subgroups can be established. No definite allergen-recognition pattern was associated with the type of allergic reactions to kiwi. One of 5 patients with kiwi allergy was not allergic to pollen, and these patients had the highest risk of systemic reactions to kiwi.
Allergy Department, Fundación Jiménez Díaz, Madrid, Spain.
Ana
A
Alemán
Joaquin
J
Sastre
Santiago
S
Quirce
Manuel
M
de las Heras
Jerónimo
J
Carnés
Enrique
E
Fernández-Caldas
Carlos
C
Pastor
Ana Belén
AB
Blázquez
Fernando
F
Vivanco
Javier
J
Cuesta-Herranz
D029042:Actinidia / Q000009:adverse effects* / Q000235:genetics / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000235:genetics; D000595:Amino Acid Sequence; D029662:Betula / Q000009:adverse effects; D001628:Beverages; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D005512:Food Hypersensitivity / Q000150:complications / Q000175:diagnosis* / Q000209:etiology; D005638:Fruit / Q000009:adverse effects / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007159:Immunologic Tests; D008297:Male; D008875:Middle Aged; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications
D000485:Allergens; D007073:Immunoglobulin E