Individuals with peanut allergy often avoid tree nuts, yet the rate of tree nut allergy in peanut allergic patients is often cited as low as 7%. Peanut allergy affects 1-2% of individuals in the U.S. and its increasing. The current management is strict avoidance and prompt use of epinephrine for systemic reactions which can occur up to 15% of the time in peanut allergic patients. Historically, peanut allergic patients were advised to avoid tree nuts because of concerns of cross contamination or risk of developing a tree nut allergy.
Avoidance may be unnecessary, as tree nuts can be an important source of nutrition. They can also reduce the risk of cardiovascular disease, cancer and mortality. Recently, peanut allergic individuals have been consuming tree nuts when there is no evidence of allergy. A recent study evaluated peanut allergic individuals and their tree nut sensitization patterns.
Peanut allergic patients have other atopic diseases:
- Eczema 52.7%
- Allergic Rhinitis 63.2%
- Asthma 41.9%
- Other food allergies 51.5%
The rate of sensitization (skin test and serum IgE) for various nuts for peanut allergic patients are below:
Emerging data have shown that peanut-allergic individuals with tree nut sensitization will frequently pass oral food challenges in the office and the rate of true tree nut allergy is much lower than reported figures. So potentially the individuals who can consume other tree nuts may be much higher.
In the study almonds were the most commonly consumed tree nut. The serum IgE levels for cashew and pistachio were significantly higher compared to other tree nuts, but nearly 60% of peanut allergic individuals were still offered challenges.
The data supports that peanut allergic individuals are commonly sensitized to tree nuts, but they still may be able to be consumed. A careful evaluation of skin testing, blood IgE testing and oral food challenges can help see if they can be consumed.