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Staphylococcus Aureus Colonization Is Associated with Increased Peanut Allergy Sensitization in Children with Atopic Dermatitis (AD)
Sunday, March 6, 2016: 2:45 PM
Room 515A (Convention Center)
Andrea L Jones, MD, ,
Rationale: Animal models have demonstrated that S. aureus can induce peanut allergy and loss of T-cell tolerance.  This study investigated the association of S. aureus colonization and peanut allergy in children with AD.  

Methods: The NJH Research Database was queried for patients ages 0-18 years with AD and S. aureus culture from 3/2008-3/2015 (Data Set Identifier: 337-4722-04142).  Peanut allergy was analyzed according to S. aureus colonization.  Peanut allergy was defined as IgE to peanut >15 KuA/l, which correlates to a >95% probability of food challenge reaction in patients with AD. 

Results: 718 patients were identified: 139 (19.4%) MRSA, 411 (57.2%) Methicillin sensitive S. aureus (MSSA) and 168 (23.4%) with no S. aureus.  Mean IgE to peanut [KuA/l] was higher in the MRSA versus MSSA group (59.2 vs 48.2, p=0.02) and no S. aureus (59.2 vs 25.7, p=<0.001).  Peanut allergy prevalence was higher in the MRSA versus MSSA group (56.8% vs 46.75% had IgE peanut >15 KuA/l, p=0.04).  Peanut allergy prevalence was higher in the S. aureus versus no S. aureus group (56.8% vs 13.7% had IgE peanut >15 KuA/l, p=<0.001).  No difference in food allergy prevalence was seen in the MRSA versus MSSA group for wheat, egg white, cow milk or soybean. 

Conclusions: Children with AD and S. aureus colonization demonstrate a significantly higher prevalence of peanut allergy sensitization.  This effect is most significant in AD with MRSA colonization and is not seen with wheat, egg white, cow milk, and soybean.  S. aureus may play an important role in the development of peanut allergy