A. Oehling et al., SKIN MANIFESTATIONS AND IMMUNOLOGICAL PARAMETERS IN CHILDHOOD FOOD ALLERGY, Journal of investigational allergology & clinical immunology, 7(3), 1997, pp. 155-159
According to Hansen's contact rule, the digestive system should be con
sidered as the main shock organ, yet in food allergy, this is not the
case. Very often specific food triggers clinical manifestations not in
volving the digestive system; that is, reactions are manifested either
in the respiratory system, as asthma or rhinitis, or in the skin. In
these cases the BALT (broncho-alveolar lymphoid tissue) and GALT (gast
rointestinal lymphoid tissue) units play a basic role in the sensitiza
tions. The purpose of this study was to determine the most frequent sk
in manifestations of food allergy among children, and the most frequen
tly involved foods. We also thought it interesting to evaluate the dia
gnostic reliability of the different standard immunological parameters
utilized by the study team in food allergy. All patients underwent in
tracutaneous tests with 12 groups of the most frequent food allergens,
as well as serum IgE, antigen-specific IgE against foods, and antigen
-specific histamine release tests. Antigen-specific lgG4 determination
was performed in some cases. The results obtained confirmed previous
studies, the most common manifestations being: angioedema (48%), follo
wed by urticaria (31%) and atopic dermatitis (21%). Regarding the freq
uency of sensitization to different food allergens, in mono- or polise
nsitization, fish and egg stand out in our environment. Certain food a
llergens are more frequently responsible for specific skin manifestati
ons. Thus, for fish sensitization the most frequent skin manifestation
is atopic dermatitis (50%); for egg sensitization, angioedema is the
most frequent skin manifestation (50%); and for milk, urticaria (50%).
Finally, and in agreement with previous works regarding the diagnosti
c reliability of in vitro techniques, we found that the histamine rele
ase test offered the highest percentage of diagnostic reliability. Onl
y for sensitization to milk proteins did antigen-specific IgE demonstr
ate higher reliability. Once again, we stress that our main problem is
the lower reliability of skin tests against food allergens than again
st inhalant allergens. We emphasize the importance of food as a major
factor in the etiopathogenesis of atopic dermatitis, as well as the ne
ed to complement the study, when possible, by means of the in vitro te
chniques described.