"Everyone's Gone Nuts" -- A doctor responds to the Harper's Magazine article

Can asthma be part of an allergic or anaphylactic reaction?

MP: Yes. Anaphylaxis can trigger asthma attacks that are notoriously difficult to treat. Wheezing, cough, chest tightness, and shortness of breath commonly occur during an asthma attack but are also life threatening symptoms seen during anaphylaxis (Wang. Clinical and Experimental Allergy, 37, 651-660). In some cases, respiratory symptoms can be the only manifestation (Moneret-Vautrin et al. Allergy. 2005: 60: 443-451). Anaphylaxis presenting in this way must be quickly treated with epinephrine. Prior to the advent of albuterol, epinephrine was the drug of choice for asthma exacerbation. When in doubt, use your epinephrine and call 911.

SM: How real is the threat from so-called "second-hand exposure," like a kiss, to an allergen?

MP: Allergens can be transferred through saliva, so the second-hand exposure threat is real but entirely avoidable. Rosemary Hallett and colleagues at the University of California Davis School of Medicine reviewed data collected on 379 subjects with self-reported immediate nut or seed allergy and found that 20 subjects (5.3%) reported that they experienced reactions from kissing. Most of these reactions were mild but 20% did experience respiratory symptoms (Hallett et al. N Engl J Med 2002; 346:1833-4). Studies in other countries showed that people with food allergies reported that they experienced allergic symptoms after having "close physical contact (for example, kissing) with someone who recently ate something they were hypersensitive to (Eriksson et al. Journal of Investigational Allergology and Clinical Immunology. 2003 13(3):149-154).

In 2006, Maloney and colleagues conducted a study measuring the amount of peanut protein in 1 ml of saliva at certain times after eating a peanut butter sandwich and following various interventions. The study showed that soon after eating peanut butter salivary levels of peanut protein were high enough in some to cause a reaction. Additionally, 13% of subjects had detectable peanut protein in the saliva after 1 hour. No subjects had detectable salivary peanut protein several hours later and after eating a peanut-free meal. This study supports the reports of patients experiencing symptoms after kissing and demonstrates that oral contact with saliva, such as from sharing utensils or cups, can contain significant amounts of allergen and should be avoided. Additionally this study gives some guidance as far as interventions that can reduce the risk of a reaction other than complete avoidance (Maloney et al. JACI. V 118, (3) 719-724).

SM: Broussard quotes a CDC statistician who says, "There are far too few recorded incidents of anaphylactic shock triggered by food allergies to draw any sound epidemiological conclusions: 'We can't find any hard data that supports the severity'."

MP: Studies determining the rates anaphylaxis and death from anaphylaxis have been notoriously difficult to conduct. Until recently, there has been little consensus as to its definition or clinical criteria and it is widely thought that it is underreported and underdiagnosed (Lieberman et al. Annals of Allergy, Asthma & Immunology. 2007;98:519-523).