Is atopic comorbidity increased in proctocolitis?

Background: Allergic march refers to the association of multiple allergic diseases but current understanding primarily focuses on immunoglobulin E (IgE) mediated food allergies (FA) (IgE-FA). The impact of non‐IgE-FAs on allergic march remains unclear. Objective: To determine whether food protein‐induced allergic proctocolitis (FPIAP), a non‐IgE-FA, coexists with other allergic diseases during follow-up and to identify predictive factors. Methods: Eighty-four patients diagnosed with FPIAP who had been followed up for at least 3 years and 89 age- and gender-matched controls were compared for the presence of concomitant allergic conditions. Results: Patients with FPIAP who were followed up regularly for at least 3 years were evaluated for the presence of concurrent allergic diseases at a median (interquartile range [IQR]) age of 50 months (47‐54 months), whereas, in the age- and gender-matched control group, the median (IQR) age at evaluation was 51 months (47.5‐57.5 months). Asthma, allergic rhinitis (AR), and IgE-FA rates in the FPIAP group were 29.8% (n = 25), 29.8% (n = 25), and 15.5% (n = 13), respectively, compared with 14.6% (n = 13), 13.5% (n = 12), and 3.4% (n = 3), respectively, in the control group. Asthma, AR, and IgE-FA were significantly more frequent in the FPIAP group (p = 0.03, p = 0.02, p = 0.01, respectively). Atopic dermatitis in those under the age of 2 years was more prevalent in the FPIAP group (38.6%, [n = 32]) compared with the controls (10.6% [n = 9]) (p = 0.001). Although vomiting at onset was identified as a predictive factor for asthma, maternal rhinitis and delayed introduction of complementary feeding were associated with an increased risk of developing AR in the FPIAP group. Conclusion: This study demonstrated a higher rate of asthma, AR, and IgE-FA in patients with FPIAP compared with age- and gender-matched controls. These findings emphasize the importance of increasing awareness of the potential coexistence of FPIAP with other allergic diseases.