ABSTRACT
Background: Tree nut allergy is usually life-long and
potentially life-threatening. Standard of care consists of strict
avoidance of the culprit nut and symptomatic treatment of accidental
reactions.
Objective: To evaluate the potential therapeutic options for
desensitization of patients with IgE-mediated tree nut allergy, focusing
on, but not limited to, immunotherapy.
Methods: We systematically searched three bibliographic
databases for studies published until July 2022 for active treatments of
IgE-mediated allergy to tree nuts (walnut, hazelnut, pistachio, cashew,
and almond) with allergen-specific immunotherapy (AIT) using oral (OIT),
sublingual (SLIT), epicutaneous (EPIT) or subcutaneous (SCIT) delivery,
or with other disease-modifying treatments.
Results: We included 17 studies (three randomized,
double-blinded, placebo-controlled, five quasi-experimental prospective
cohorts, five prospective cohorts, two retrospective cohorts, and two
case reports. Three studies investigated sublingual immunotherapy, five
investigated oral immunotherapy to a single tree nut, and six used
multi-food oral immunotherapy with (four) or without (two) omalizumab.
The remaining studies investigated the effectiveness of monoclonal
antibodies in multi-food allergic patients, including patients with a
tree nut allergy. The heterogeneity of the studies prevented pooling and
meta-analysis.
Conclusion: Even though strict avoidance remains the standard
of care for patients with tree nut allergy, alternative approaches have
been tested in clinical trials and real-life studies. These new concepts
require further investigation with more well-designed studies including
well-characterized nut allergic patients before implementing them in
daily clinical practice.
KEYWORDS: Allergy treatment, food allergy, immunotherapy,
management, tree nuts