Severe Anaphylactic Reactions to Home Doses of Oral Immunotherapy for Food Allergy

Food Sublingual Immunotherapy: Safety and Simplicity of a Real Food Updosing Protocol

BACKGROUND

Sublingual immunotherapy (SLIT) using food extracts is safe and effective in desensitizing patients with food allergy, yet not often used in clinical practice.

OBJECTIVES

To propose a cost-effective, expedited SLIT protocol using real food.

METHODS

Patients with food allergy aged 5 to 50 years (median, 11 years) initiated food SLIT in a single-clinic setting. The daily maintenance dose was 4 to 11 mg protein in 0.1 to 0.5 mL volume, depending on the food. Some foods were available in liquid form at the local grocery (milk, egg white liquid, and cashew/walnut/sunflower/hazelnut milk), whereas others were prepared in the office using flour and 50% glycerin saline (peanut/sesame/wheat). The first cohort of 20 patients began dosing at a 1:1000 dilution, the next 30 patients at 1:100 dilution. An exercise challenge was performed in a subset of patients on maintenance dosing to evaluate the need for a predose or postdose rest period.

RESULTS

The 1:1000 and 1:100 cohorts both completed day 1 without adverse reactions beyond itchy mouth. There were no systemic reactions requiring epinephrine throughout the study period and 88% reached their maintenance dose. Skin testing of 6-month-old peanut flour solution was not diminished from fresh solution and similar to food extract. Exercise challenge test results in 12 patients were negative.

CONCLUSIONS

Allergen extract food SLIT as used in published trials has limitations of cost and multiple office visits. Inexpensive real food, at the same or slightly higher protein dose, was well tolerated in 4 updose visits, a minimum of a week apart. Unlike food oral immunotherapy, a predose or postdose rest period may not be necessary.

Current options in the management of tree nut allergy: A systematic review and narrative synthesis

Tree nut allergy is a lifelong and potentially life-threatening condition. The standard of care is strictly avoiding the culprit nut and treating accidental reactions symptomatically. To evaluate potential therapeutic options for desensitizing patients with IgE-mediated tree nut allergy, we systematically searched three bibliographic databases for studies published until January 2024. We looked for active treatments of IgE-mediated allergy to tree nuts (walnut, hazelnut, pistachio, cashew, almond, pecan, macadamia nut, and brazil nut). We focused on allergen-specific immunotherapy (AIT) using oral (OIT), sublingual (SLIT), epicutaneous (EPIT), or subcutaneous (SCIT) delivery, or other disease-modifying treatments. We found 19 studies that met our criteria: 3 studies investigated sublingual immunotherapy, 5 studied oral immunotherapy to a single tree nut, and 6 used multi-food oral immunotherapy with or without omalizumab. The remaining studies investigated the effectiveness of monoclonal antibodies or IgE-immunoadsorption in multi-food allergic patients, including patients with tree nut allergy. The heterogeneity of the studies prevented pooling and meta-analysis. Oral immunotherapy, single or multi-nut, with or without omalizumab, was the most studied approach and appears effective in conferring protection from accidental exposures. Omalizumab monotherapy is the only approved alternative management for reducing allergic reactions that may occur with accidental exposure.

Consumption of cow's milk formula in the nursery and the development of milk allergy

BACKGROUND

The effect of the amount of transient cow's milk formula (CMF) consumed during the first days of life on IgE-cow's milk allergy (IgE-CMA) is unknown.

METHODS

A cohort of 58 patients with IgE-CMA was identified from a large scale population-based study of 13,019 infants followed from birth. A group of 116 infants matched for sex and breastfeeding only duration (beyond the nursery period), and another random group of 259 healthy infants were used as controls. Parents were interviewed and the infants' medical records were searched to assess CMF consumption in the nursery.

RESULTS

While 96% of the mothers of the 174 infants (58 with Cow's milk allergy and 116 controls) reported on exclusive breastfeeding during the stay in the nursery, CMF consumption was documented in 96 (55%) of the infants. Of those, most (57; 59%) received one to three feedings, 20 (21%) received four to nine feedings, and 19 (20%) received ≥10 feedings. Fewer formula feeds (1-3) were significantly more common in the allergic group than ≥4 feeds (p = 0.0003) and no feeds at all (p = 0.02) compared to controls (n = 116). Of those exclusively breastfed in the nursery, 13/23 allergic infants (57%) introduced CMF at age 105-194 days (the period with highest-risk for IgE-CMA) compared to 33/98 (34%) from the random control group (n = 259) (p = 0.04).

CONCLUSIONS

Most infants end up receiving few CMF feeds in the nursery. Transient CMF in the nursery is associated with increased risk of IgE-CMA.

Baked milk and egg diets revisited

Most children with milk and egg allergy are nonreactive to modified forms of milk and egg in bakery products such as muffins because of conformational changes in proteins. These baked milk (BM) and baked egg (BE) diets have become commonplace in the management of milk and egg allergy, respectively. Current laboratory- and skin test-based diagnostic approaches remain limited in their ability to predict BM/BE tolerance, resulting in various approaches to introduce these foods. One approach to introduce BM/BE is to offer a medically supervised oral food challenge and then advise dietary introduction of baked products for children who have tolerance. Another approach is adapted from a home-based protocol of graded ingestion of BM or BE originally intended for non-IgE mediated allergy, often referred to as a "ladder." The ladder advises home ingestion of increasing amounts of BM or BE. For children who have allergy to BM or BE, the ladder is essentially oral immunotherapy, although not always labeled or recognized as such. Risk assessment and education of patients suitable for home introduction are essential. A home approach that may be called a ladder can also be used to escalate diets after demonstrated tolerance of baked forms by introducing lesser cooked forms of milk or egg after tolerating BM or BE. A randomized controlled trial provided clear evidence that baked diets can hasten the resolution of IgE-mediated milk allergy. Moreover, BM/BE foods have an emerging role in the treatment of non-IgE-mediated allergy. There is tangential evidence for BM and BE diets in the prevention of IgE-mediated allergy.