Sensitization to lupine flour: is it clinically relevant?

Area of Science:

• Allergy and Immunology
• Food Science
• Clinical Medicine

Background:

• Lupinus angustifolius (blue lupine) is increasingly used in human and animal food products.
• Despite its presence in various foods, clinical anaphylaxis to lupine flour is infrequently reported.

Purpose of the Study:

• To investigate the clinical significance of sensitization to lupine flour in patients with suspected food allergies.
• To determine the prevalence and characteristics of true lupine allergy.

Main Methods:

• Skin prick tests (SPT) with lupine, peanut, and soy extracts were conducted on 372 patients with suspected food allergies.
• Double-blind placebo-controlled food challenges (DBPCFC) and specific IgE measurements were performed in lupine-sensitized individuals.

Main Results:

• Of 372 patients, 22 showed positive SPT to lupine flour.
• Eight out of nine patients undergoing DBPCFC for lupine sensitization had negative challenges; one patient experienced significant symptoms.
• Specific IgE to L. angustifolius was positive in all nine challenged patients, indicating sensitization, but not necessarily clinical allergy.

Conclusions:

• Clinical lupine allergy is uncommon, with an estimated prevalence of 0.27-0.81% among referred patients.
• Sensitization to lupine flour is often not clinically relevant, potentially due to cross-reactivity with peanut.
• While rare, significant lupine allergy can occur, necessitating careful diagnostic evaluation in selected cases.