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*New papers thread* Two new papers published today that are the culmination of years of work and that may inform some controversies about early peanut introduction. With @MichaelPistiner, @WayneShreffler, @JenniferDantzer
https://authors.elsevier.com/a/1cRQDKs2x3t2f ,
https://authors.elsevier.com/a/1cRQHKs2x3t2l 1/x
https://authors.elsevier.com/a/1cRQDKs2x3t2f ,
https://authors.elsevier.com/a/1cRQHKs2x3t2l 1/x
When the LEAP study showed that peanut introduction at 4-11 mo of age dramatically reduced the risk of peanut allergy, the NIH released guidelines recommending early peanut. Their recommendations to screen high-risk children prior to introduction were controversial. 2/x
Who should be screened? How? My bias was that risk of peanut allergy was low & screening before peanut introduction didn’t make sense.
We designed a study where we enrolled children 4-11 mo old without known peanut exposure or testing for peanut allergy but were a member of a potential “high-risk group”: (1) moderate-severe eczema, (2) non-peanut allergy, (3) family member w/peanut allergy. 4/x
We wanted to know what % of each group had peanut allergy and how to test. We did SPT, IgE and introduced peanut in the office on 321 kids at johns Hopkins and MGH. We found: (1) very high rates of peanut allergy among those with eczema (>18%)
(2) very low rates in those with family history of peanut allergy but no eczema
(3) increasing risk with age: 30% increased odds per month among those with eczema (4) increased risk with more severe eczema (higher SCORAD) (5) couldn’t make firm conclusions about other food allergy because small N, but other food allergy increased risk among those with eczema
(6) for testing, ara h 2 specific IgE was best, with high specificity and pretty good sensitivity. With peanut specific IgE and SPT, there are LOTS of false positives. Other peanut component IgE did not add information.
Strategies involving SPT and peanut specific IgE lead to MANY food challenges (or false positive diagnoses)
So what? (1) introduce peanut early, especially if there’s significant eczema. (2) even so, may not be enough, so need other prevention methods and treatments, (3) screening might be appropriate for some patients, but not for siblings of peanut allergic children
(4) maybe guidelines should change to use just ara h 2 specific IgE when screening is done. end
