In 2014, researchers reported that in comparison to untreated mice, newborn mice treated with antibiotics produced higher levels of allergen-specific IgE and IgG1 antibodies when sensitized with peanut allergen. Now a new study published in Allergy, Asthma & Clinical Immunology (Aug. 2016) has linked antibiotic use during infancy with increased odds of developing food allergy in childhood.
Investigators at the University of South Carolina found that young children diagnosed with food allergy were more likely to have been prescribed antibiotics during the first year of life than were same-age children who did not have food allergies. A stronger association between early antibiotic use and food allergy was seen when the definition of food allergy was limited to include only those children prescribed an epinephrine auto-injector.
The study reviewed Medicaid billing data for South Carolina children born between 2007 and 2009. The 1,504 children identified anonymously as food allergy cases received at least one diagnosis code associated with food allergy during a doctor visit or hospitalization in 2010. For each case, four matched controls were selected who shared the same birth month, birth year, sex, and race/ethnicity.
Antibiotic use during infancy was significantly more common in the food allergy cases. From birth to 12 months, 56.6 percent of food allergy cases and 52.0 percent of controls were prescribed antibiotics. Researchers noted that food allergy patients are more likely to suffer from other allergic conditions that can result in treatment with antibiotics. To account for this, the models used to compare outcomes were adjusted for atopic dermatitis (eczema), asthma and wheeze.
Taking any antibiotic during the first year of life was associated with increased odds of food allergy, but the strength of this association varied among different classes of antibiotics. Cephalosporin and sulfonamide antibiotics showed the strongest associations with food allergy.
Food allergy cases were treated with a higher average number of antibiotic prescriptions, receiving 1.53 prescriptions during infancy compared to 1.17 for controls. The odds of a food allergy diagnosis grew as the number of antibiotic prescriptions increased. In proposing possible explanations, the authors observed that multiple courses of antibiotics could make impairment of gut bacteria more likely and would increase the likelihood of a new food being introduced during antibiotic treatment.