Transepidermal Water Loss Monitoring During Oral Food Challenge Reduces Anaphylaxis

A study presented at the 2025 American Academy of Allergy, Asthma, & Immunotherapy (AAAAI) annual meeting in San Diego from February 28 – March 3 demonstrated that real-time monitoring of transepidermal water loss during an oral food challenge reduces anaphylaxis rates and epinephrine use.¹

Oral food challenge may be the gold standard for a food allergy diagnosis, but people may be skeptical of doing this due to potential risks—namely, anaphylaxis.

“I think the overarching thing we hear is that it's a difficult thing to do oral food challenges in a busy clinical practice,” David R. Stukus, MD, told HCPLive back in 2018.² “You need to have dedicated exam rooms where you can stay for several hours, and you need to have support staff that's available in case an allergic reaction occurs so you can drop everything and treat them immediately if that happens. Working that out in an outpatient center that may be miles away from a medical facility or an emergency room is understandably logistically challenging for a lot of folks.”

Research has shown that transepidermal water loss increases during food anaphylaxis, so investigators sought to see if monitoring transepidermal water loss could reduce the risk of anaphylaxis.₁

The team, led by George Freigeh, MD, from the University of Michigan, conducted a double-blind, randomized control trial to evaluate the outcome of using real-time transepidermal water loss monitoring as a stopping criterion for an oral food challenge. Investigators compared real-time transepidermal water loss monitoring as a stopping criterion for an oral food challenge with the standard oral food challenge procedure.

The study included children aged 6 months – 5 years old who had an allergist-confirmed diagnosis of a peanut food allergy with a prior history of reaction and peanut sensitization. Participants qualified for the trial if they had the following levels: wheal ≥ 3 mm, total peanut IgE ≥ 5 .0 kUa/L, or ARA H2 of > 0.32 kUa/L. Investigators randomized the 40 participants into the intervention (n = 18) or control arm (n = 22).

The intervention arm determined the stopping criteria of an oral food challenge by transepidermal water loss monitoring. The challenge was stopped if the transepidermal water loss rose 1 g/m2 per hour. This was accompanied by either an objective allergic symptom or dose-limiting symptoms per CoFAR criteria—whichever arrived first.

The control arm determined the stopping criteria of an oral food challenge by only dose-limiting symptoms per CoFAR criteria.

Investigators found no significant difference in reaction rate between arms. However, they did observe a significantly lower rate of anaphylaxis among children in the intervention arm, compared with the control arm (63% vs 100%; P = .01). Moreover, children in the intervention arm had a significantly lower rate of epinephrine use than those in the control arm (50% vs 86%; P = .04).

“Real-time monitoring of [transepidermal water loss] during [oral food challenge] can lead to reduced anaphylaxis rates and epinephrine use, which may ultimately increase accessibility and safety of [oral food challenges],” investigators concluded.

References

1. Freigeh, George, O, K, Troost, J, et al. Real-time Transepidermal Water Loss Monitoring During Oral Food Challenge Leads to Decreased Anaphylaxis: A Randomized Control Trial. Journal of Allergy and Clinical Immunology, Volume 155, Issue 2, AB456. https://www.jacionline.org/article/S0091-6749(24)02344-3/fulltext

2. Castles, T. When and How to Conduct Oral Food Challenges. HCPLive. November 19, 2018. https://www.hcplive.com/view/when-and-how-to-conduct-an-oral-food-challenge. Accessed February 27, 2025.