Diagnostic Accuracy of Lipid Transfer Proteins (LTPs) Specific IgE Assay in Food Allergy: A Systematic Review

The aim of this systematic review was to evaluate the diagnostic accuracy of molecular-based LTPs serum sIgE for the diagnosis of food allergies in patients with suspected allergy to one of the LTPs-containing foods. Cohort, prospective or retrospective cross-sectional studies were considered for inclusion in this review. Oral food challenge (both open and double-blind placebo-controlled) was the reference standard for the diagnosis. PubMed (MEDLINE), Web of Science, Scopus, and ClinicalTrial.org were searched for relevant papers. The risk of bias was assigned by the QUADAS-2 tool. Data were reported as the sensitivity and specificity. The study protocol was registered in the PROSPERO database (CRD42022321985). Fifteen articles, including 2395 individuals, were included. The sensitivity of Ara h 9 for peanut allergy diagnosis ranged from 6 to 61%; the specificity ranged from 57 to 100%. The Cor a 8 sensitivity ranged from 11 to 43%, with the specificity ranging from 59 to 94%. Ara h 9 and Cor a 8 serum sIgE may be useful for confirming the diagnosis of peanut and hazelnut allergy in symptomatic patients, although the diagnostic accuracy is limited by the low sensitivity. More investigation on other LTPs and in adult populations may be important to define the clinical role of this test in food allergy diagnostics.