Symptoms, treatment, and main allergens
Urticaria was reported by 56 patients in the anaphylaxis group (39.2%)
as being present during the initial reaction to the food, compared to
only 17 patients in the non-anaphylaxis group (18.5%) (p-value< 0.0008). The symptom most frequently presented in the
anaphylaxis group was abdominal pain (60.8%), followed by urticaria
(49.0%). Other patients’ characteristics are shown in Table 1.
Most patients with anaphylaxis
were treated with oral antihistamines (93.7%) and oral corticosteroids
(69.2%); adrenaline intramuscular injection was administered only in
47.6% of them (Table 2).
When considering the most frequent food responsible for a positive OFC,
the main group includes tree nuts (31.9%), followed by peanuts (27.7%)
and eggs (11.1%) (Figure 1). As for tree nuts (Figure 1), cashew nuts
were the most commonly one responsible for allergies (22.7% of this
subgroup and 7.2% of the whole anaphylaxis group).
We assessed the different foods responsible for reactions during the OFC
and found legumes (besides peanut) were those more frequently associated
with anaphylactic reactions compared to non-anaphylactic ones (90.9%
vs. 9.1%), while patients with a positive OFC to seafood, excluding
fishes, reacted mainly without experiencing anaphylaxis (30.0% vs.
70.0%), as shown in Figure 2. Peanuts, the most common allergen
associated with a positive OFC, were responsible for anaphylaxis in
allergic patients in 70.8% of cases. As for tree nuts, almonds
triggered anaphylaxis in every positive OFC; on the other hand, Brazil
nuts, in the case of a positive OFC, were never associated with
anaphylaxis (Figure 2).