Background Cystic fibrosis (CF) is a complex disorder with multisystem involvement. Although we used to believe that an association between CF and food allergies is rare and more frequently a false diagnostic, in the late years, as food allergies’ prevalence is rising, the association between these two disorders is becoming more common.

Aim the aim of the study was to determine food allergy prevalence in cystic fibrosis patients treated at the Mother and Child Care Institute ‘Alessandrescu-Rusescu’ between 2011–2016.

Method we conducted a five years retrospective study between 2011–2016 on 68 cystic fibrosis patients. Age of CF diagnostic was between 2 months and 10 years. We followed the cases with poor nutritional status despite PERT and proton pump inhibitors therapy and the association with cutaneous manifestations. We performed allergen specific IgE antibody test (lactalbumin, casein, beta lactoglobulin, egg, carrot, soya, nut, peanut, wheat, bovine serum albumin).

Results 8 out of 68 CF patients treated in our centre had food allergies, with a 11,76% prevalence. 6 of them have milk protein allergy, 1 with egg white allergy and 1 patient with multiple allergies (milk protein, egg, wheat, peanuts).

Conclusion it is important to further investigate possible comorbidities in CF patients with poor nutritional status and persistent digestive symptomatology despite adequate nutrition and adherence to PERT therapy. Food allergies seem to be one of the most frequent associations, surpassing celiac disease. Treatment conduct and nutritional recovery in these cases represent a milestone even for experienced clinicians.